dynamically diagnosing the human periodontium and the dental implant-bone interface

periotest deviceabout Periotest device

References: ... 1989 1990    1991 1992    1993 1994    1995 1996    1997 1998    1999 2000    2001 2002    ...

Conventional and early loading of unsplinted ITI implants supporting mandibular overdentures.
Clin Oral Implants 13(6):603-9 (2002)
80 and over, Alveolar Bone Loss, Cephalometry, Dental Abutments, Dental Implants, Dental Prosthesis, Overlay, Follow-Up Studies, Human, Middle Age, Osseointegration, Periodontal Index, Prospective Studies, Radiography, Time Factors
The aim of this study was to compare the success rates after 1 and 2 years of conventionally and early loaded pairs of unsplinted ITI implants supporting mandibular overdentures in edentulous patients. Twenty-four participants (age range 55-80 years) were randomly allocated with maximum concealment to two treatment groups. In the first group, the implants were allowed to heal for 12 weeks before being functionally loaded (control) and the second group had 6 weeks of healing with identical loading. All participants had new conventional complete maxillary and mandibular dentures prior to the study. Two sandblasted large-grit acid-etched (SLA) surface ITI implants were placed in the mandibular interforaminal area, following a standardized nonsubmerged surgical protocol. After 6 or 12 weeks of healing, matrices were processed into the fitting surface of the pre-existing mandibular dentures and the implants loaded. Implant success was determined using mobility tests and radiographs taken at baseline and 52 and 104 weeks after surgery. Clinical peri-implant parameters were also documented. Results showed all implants successfully osseointegrated, according to accepted criteria, after 2 years. Mean loss of crestal bone height after 1 year was 0.35 +/- 0.22 mm (control) vs. 0.27 +/- 0.18 mm (test). After 2 years this reduced to 0.09 +/- 0.06 mm (control) vs. 0.12 +/- 0.17 mm (test). The mean Periotest value after 1 year was -4.9 (control) vs.-3.78 (test). After 2 years, the mean resonance frequency value for the control implants was 6797 Hz [mean implant stability quotient (ISQ) = 64.77] and for the test implants 6670 Hz (mean ISQ = 62.0). Shortened loading periods for these ITI implants did not cause any statistically significant differences in osseointegration or peri-implant parameters. We conclude that pairs of unsplinted SLA-surface ITI implants can be successfully loaded with mandibular overdentures 6 weeks after surgery.

Influence of implant geometry and surface characteristics on progressive osseointegration.
Int J Oral Maxillofac Implants 17(6):811-5 (2002)
Coated Materials, Biocompatible, Dental Implantation, Dental Prosthesis, Durapatite, Human, Osseointegration, Surface Properties
PURPOSE: Although no currently available technique for the measurement of osseointegration is entirely satisfactory, 3 clinical variables can be reasonably associated with the process: probing depth, micromobility, and crestal bone height. Micromobility can be quantified to some extent with the use of the Periotest, a commercially available instrument In this investigation, the influence of surface characteristics and geometry upon Periotest value (PTV) and probing depth measurements was studied. MATERIALS AND METHODS: In a multicenter trial, 120 healthy edentulous patients received 5 or 6 implants in the anterior mandible and were followed for 3 years. A total of 634 implants were placed. Every patient received at least 1 implant of each of 3 types: threaded titanium plasma-sprayed (TPS), threaded hydroxyapatite-coated (HA), and cylindric HA-coated. A randomization schedule assured that approximately equal numbers of each type of implant were placed and that they were uniformly distributed over the arch. RESULTS: Of the 4 tested combinations of dependent and independent variables, the only statistically significant (P < .05) effect was that of coating on PTV. At 1 year after prosthetic restoration, the mean PTV for HA-coated threaded implants was -5.36 +/- 1.24, compared with -4.86 +/- 1.70 for TPS implants. This difference steadily declined in magnitude and significance, until, after 3 years, the groups were indistinguishable. DISCUSSION: This study agrees with the previous observations that HA coating tends to accelerate the initial rate of osseointegration. The absence of a difference between threaded and cylindric implants confirms that the PTV responds to micromobility near the surface, on a scale much smaller than such gross geometric features. CONCLUSION: On the basis of these results, one may conclude that HA-coated implants exhibit a more rapid decrease in micromobility than do TPS implants of identical geometry.

Implant-retained mandibular overdentures with ITI implants
Clin Oral Implants Res 13(5):495-501 (2002)
Alveolar Bone Loss, Bone Resorption, Comparative Study, Dental Abutments, Dental Implants, Dental Plaque Index, Dental Prosthesis, Dental Restoration Failure, Follow-Up Studies, Gingival Hemorrhage, Human, Osseointegration, Periodontal Pocket, Prospective Studies, Time Factors
This prospective study has been designed to compare the results of immediate and delayed loading of implant-retained mandibular overdentures after a 2-year follow-up. Twenty patients have been randomly divided into two groups. Group 1 patients (test group) received four ITI implants in the intraforaminal area of the mandible. Octa abutments were immediately screwed on implants; 2 days after surgery, the implants were rigidly connected with a U-shaped Dolder gold bar and loaded with an overdenture. Group 2 patients (control group) received, in the same area, the same type and number of implants, which were left to heal according to the standard protocol. At 3-4 months, Octa abutments were screwed on the implants and the same prosthetic procedure of the test group was applied. The minimum follow-up period lasted 2 years, with recall appointments at 2 weeks, 1, 3, 6 months, 1 year and every following year postoperatively, evaluating: MPI, MBI, PD, Periotest and radiographic peri-implant bone resorption. Success criteria according to Albrektsson et al. were used. Only one implant out of the 40 of group 2 failed, whereas none failed in group 1. No statistical difference of the clinical parameters evaluated was noticed in the two groups. Therefore, immediate loading of implants, if connected with a U-shaped bar, can provide the same results of the 'traditional' technique as far as osseointegration and short-term survival rates of implants are concerned. Moreover, this method significantly shortens the treatment period, thus increasing patient satisfaction.

Clinical response to experimental forces and non-surgical therapy of teeth with various alveolar bone loss
Dent Traumatol JID - 101091305 18, 267-274 (2002).
therapy/Alveolar Bone Loss/Periodontitis/Trauma
Firm lateral force is necessary for the thorough removal of calculus during scaling and root planning (SRP) with hand instruments. However, this firm lateral force should be applied to root surfaces without considering the tooth's loss of supporting tissues. The purpose of the present study was two-fold: firstly, to evaluate the initial pain response of periodontally diseased non-molar teeth with two different levels of alveolar bone loss (ABL) to experimental lateral and vertical pull forces; and secondly, to examine the clinical response of these teeth to non-surgical therapy. Twenty patients with chronic periodontitis were specifically selected in two groups according to the level of ABL at non-molar teeth. Group I consisted of 10 patients who have 141 non-molar teeth with a radiographic evidence of 40-65% ABL. Group II consisted of 10 patients who have 132 non-molar teeth with a radiographic evidence of > or =70% ABL. All patients were systemically healthy, free of pain, and reported no current medication usage. Starting from 0 and gradually increasing an experimental lateral force with digital force gauge, and also an experimental vertical pull force with mechanical force gauge were applied to each tooth and measured. As a result of a single experimental force applied to each non-molar tooth, the initial pain response emerged in the patients was determined by means of electronic bell system used by patients themselves. Each patient was treated with SRP using specific hand instruments under local anesthesia. Plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL) and periotest values (PV scores) were compared in both groups at initial and at month 3. A mean experimental lateral force of 24.6 N and a mean experimental vertical pull force of 48.3 N caused initial pain response in group I. Initial pain response occurred with a mean experimental lateral force of 5.3 N and a mean experimental vertical pull force of 19.4 N in group II. Only group I showed statistically significant decrease in PI, GI, PD and a significant attachment gain at month 3 (P < 0.05). There was a decrease of 6 PV in group I at month 3 (P < 0.05), whereas an increase of 4 PV was observed in group II (P > 0.05). This study showed that lateral and vertical forces required for effective SRP do not cause any problem in the group with 40-65% ABL. However, they may cause trauma in the group with approximately 70% ABL. Thus, the results suggest that the degree of healing would be different in the group with > or =70% ABL and in the group with 40-65% ABL

Evaluation of implants placed with barrier membranes. A restrospective follow-up study up to five years
Clin Oral Implants Res JID - 9105713 13, 274-280 (2002).
Alveolar Bone Loss/etiology/radiography/Bone Regeneration/Bone Substitutes/Bone Transplantation/Dental Implantation,Endosseous/Follow-Up Studies/Guided Tissue Regeneration/Membranes,Artificial
This follow-up study evaluated clinical and radiographic parameters of dental implants placed in combination with guided bone regeneration with barrier membranes. All implants functioned well up to 60 months after insertion. Forty-one patients, with a total of 72 augmented implants, who participated in a regular maintenance protocol, were investigated. Annual Periotest values (median value, - 3) revealed stable periimplant conditions and sustained osseointegration. At 6 months and annually thereafter up to five years, the radiographic evaluation yielded mean bone losses of 0.8, 1.25, 1.39, 1.42, 1.42 and 1.39 mm, respectively, with a range from 0 to 3.5 mm. No implant failures or losses were recorded. The results demonstrated stable periimplant conditions up to five years after membrane-protected osseous regeneration, with no significant differences in the radiographic bone level in regard to region, jaw or bone graft. Premature membrane exposure resulted in a significantly higher crestal bone loss up to 24 months. The newly formed bone appeared to be able to withstand functional loading for up to 60 months in a predictable manner

Implant-retained mandibular overdentures with ITI implants
Clin Oral Implants Res JID - 9105713 13, 495-501 (2002).
overdentures/ITI implant/surgery/Bone Resorption/Osseointegration/Patient Satisfaction
This prospective study has been designed to compare the results of immediate and delayed loading of implant-retained mandibular overdentures after a 2-year follow-up. Twenty patients have been randomly divided into two groups. Group 1 patients (test group) received four ITI implants in the intraforaminal area of the mandible. Octa(R) abutments were immediately screwed on implants; 2 days after surgery, the implants were rigidly connected with a U-shaped Dolder gold bar and loaded with an overdenture. Group 2 patients (control group) received, in the same area, the same type and number of implants, which were left to heal according to the standard protocol. At 3-4 months, Octa abutments were screwed on the implants and the same prosthetic procedure of the test group was applied. The minimum follow-up period lasted 2 years, with recall appointments at 2 weeks, 1, 3, 6 months, 1 year and every following year postoperatively, evaluating: MPI, MBI, PD, Periotest(R) and radiographic peri-implant bone resorption. Success criteria according to Albrektsson et al. were used. Only one implant out of the 40 of group 2 failed, whereas none failed in group 1. No statistical difference of the clinical parameters evaluated was noticed in the two groups. Therefore, immediate loading of implants, if connected with a U-shaped bar, can provide the same results of the 'traditional' technique as far as osseointegration and short-term survival rates of implants are concerned. Moreover, this method significantly shortens the treatment period, thus increasing patient satisfaction

Stability of dental implants in microvascular osseous transplants
Plast Reconstr Surg JID - 1306050 109, 916-921 (2002).
Dental Implantation/blood supply/transplantation/Jaw Neoplasms/surgery/Microcirculation/Reconstructive Surgical Procedures
Microvascular iliac crest and scapula transplants have been used in reconstruction of the lower jaw following tumor surgery. It has only been with the insertion of dental implants that a satisfactory prosthetic rehabilitation of the patient has been achieved. For this study, a follow-up of 38 patients with lower jaw tumors was carried out. The patients had been treated with partial resection of the lower jaw and neck dissection with microvascular iliac crest transplants (n = 20) or microvascular scapula transplants (n = 18); this was followed with dental implants (n = 143) in the region of the transplants or the local lower jaw. One hundred thirty-nine of the 143 dental implants were loaded by prosthetic superstructures. In all patients, the implant situation was evaluated on average 2 years 5 months after implantation. Periotest values, periimplant probing depths, and contact bleeding were registered, and the extent of periimplant bone loss was defined radiographically. The clinical situation in the region of the implant was compared for both types of implants and also with the nonresected lower jaw. The average Periotest values were within the normal range for all groups. In one scapula implant, however, a better average of Periotesting, -3.3, was found compared with implants of the iliac crest with Periotest values of -0.7. A measurement of -2.1 was found for the local lower jaw, similar to that of scapula implants. Pathologic probing depths were found for all three compared groups. The radiographically determined vertical loss of bone was the same for all three groups, on average 1 mm at 27 months postoperatively. The highest incidence of sulcus bleeding was found in the scapula implant group. Thus, it can be stated that the scapula transplants provide a similar transplant site to local lower jaw bone, whereas implants in iliac crest transplants show lesser bony stability. Periimplant soft-tissue conditions are worse for both types of transplants compared with local tissue of the lower jaw

Evaluation of stability of titanium and hydroxyapatite-coated osseointegrated dental implants: a pilot study
Clin Oral Implants Res JID - 9105713 13, 75-79 (2002).
Coated Materials,Biocompatible/Dental Alloys/dental implants/Durapatite/Elasticity/surgery/Osseointegration/Titanium/Weight-Bearing/endosseous implants
An endosseous implant is described as osseointegrated when it is immobile in function. Objective measures of stability testing have been described. The Periotest is a commercially available device that is used for this purpose. This study was designed to measure stability of endosseous implants placed in the mandible. Implants were placed in the mandibular canine or first premolar area to support an overdenture prosthesis. Stability was evaluated through the use of a Periotest device at the time of implant placement and following one year of functional loading. Implant designs were either a screw-shaped titanium alloy or a hydroxyapatite-coated cylinder. A total of 54 implants were placed, 37 were titanium screw-shaped implants, while the remaining 17 were hydroxyapatite cylinders. Initial measurements of stability showed no difference due to implant type. Following one year of functional loading, titanium screw-shaped implants were more stable than hydroxyapatite implants (P < 0.05). The difference in implant rigidity following a period of functional loading may be an indication of a difference in osseointegration between the two implants used in this study

Porous-surfaced dental implants in the partially edentulous maxilla: assessment for subclinical mobility
Int J Periodontics.Restorative.Dent. 22, 184-192 (2002).
dental implants/mobility/
Abstract: Fifty patients received 151 short, porous-surfaced implants in the partially edentulous maxilla. Periotest values (PTV) were recorded at baseline and after 6 months and 1 and 2 years. For this, prostheses were removed and a standard abutment attached and tightened (20-Ncm force) to each implant. Data analysis indicated significant relationships between time in function vs PTV and implant diameter (3.5, 4.1, or 5.0 mm) vs PTV There was no relationship between PTV and implant length. PTVs were more favorable in the posterior than anterior maxilla, and better PTVs were obtained with nonsplinted as opposed to splinted implants

Treatment of replacement resorption with Emdogain--a prospective clinical study
Dent.Traumatol. 18, 138-143 (2002).
replantation/Ankylosis/Tooth/Tooth Extraction/Trauma
The present clinical study investigated the outcome of intentional replantation using Emdogain for periodontal healing following trauma-related ankylosis. Sixteen ankylosed teeth affected by replacement resorption were treated as follows: After tooth extraction, the root canal was obturated with a retrograde titanium post. Emdogain was applied to the root surface and into the extraction socket with subsequent replantation of the tooth. Evaluation parameters included horizontal and vertical Periotest scores, percussion sound and periapical radiographs. All findings were compared to those of the adjacent teeth. The mean follow-up period was 15 months (range 4-24 months). Eleven teeth showed no signs of recurrence of ankylosis: they were in full function and exhibited no pathological clinical findings. Four severely traumatized teeth demonstrated a recurrence of ankylosis after a mean period of 6 months, one tooth was lost in a second accident after 7 months. The estimated probability of 1 year without recurrence of ankylosis was P=0.66 (95% confidence interval [0.40; 0.94]). The mean survival time was 10.2 months (SD 1.1). The results indicate that treatment of replacement resorption following light to moderate trauma with replantation and Emdogain appears to prevent or delay recurrence of ankylosis in many cases

The transgingival approach for placement of distraction implants
J Oral Maxillofac Surg JID - 8206428 60, 793-796 (2002).
Alveolar Bone Loss/surgery/pathology/radiography/Alveolar Ridge Augmentation/Methods/Atrophy/Cicatrix/dental implants/Follow-Up Studies/Gingivectomy/Human/Osteotomy/Periodontitis/etiology/Periosteum/implant/complications
PURPOSE: Since 1997, distraction implants have been clinically used for alveolar ridge distraction and, later, for prosthetic treatment. While 63 patients have been treated by the authors by alveolar ridge distraction with distraction implants with an open approach, the aim of this study was to demonstrate a minimally invasive technique of distractor placement via a transgingival approach. PATIENTS AND METHODS: Twelve patients were treated with a modified surgical incision using distraction implants. A tissue punch was used to remove transgingival mucosa, and a segmental osteotomy was performed using a vestibular incision. The distracted segment was pedicled at the lingual and crestal mucoperiosteum. Distraction was carried out for 0.5 mm per day, divided into 2 to 4 turns per day. A distraction of 5 to 7 mm was performed. At the end of distraction, the distraction insert was changed into a definitive stable implant insert. Prosthetic treatment was performed 4 months after the distraction period with fixed superstructures. The follow-up was performed with the aid of dental radiographs, evaluation of peri-implant probing depths, and Periotest values (Siemens, Bensheim, Germany). RESULTS: The outcome of this technique showed minimal scarring of the gingiva with good aesthetic results, the clinical and radiologic findings were satisfying, and the Periotest values were negative at every examination. The rate of complications was low. CONCLUSION: Minimal scarring and good aesthetic and functional outcome resulted in patients with alveolar ridge distraction performed with a transgingival approach.
Clinical Department of Oral and Maxillofacial Surgery, University Hospital Graz, Auenbruggerplatz 7, A-8036 Graz, Austria alexandergaggl@kfunigrazacat

Effects of immediate loading with threaded hydroxyapatite-coated root-form implants on single premolar replacements: a preliminary report
The transgingival approach for placement of distraction implants
Int J Oral Maxillofac Implants 17, 567-572 (2002).
Prospective Studies/Methods/Human/surgery/mobility/Periotest/Gingiva/complications
PURPOSE: This prospective study evaluated the immediate loading of single, threaded, root-form implants placed in the maxillary premolar area. MATERIALS AND METHODS: Ten human subjects were included in this preliminary report. In all cases, a screw-retained temporary acrylic resin crown was placed immediately after implant surgery. The definitive screw-retained metal-ceramic crown was placed 6 months later. RESULTS: Standardized radiographs demonstrated 0.58, 0.73, 0.84, and 0.90 mm mean marginal bone loss at 1, 3, 6, and 12 months after implant surgery, respectively. Implant mobility was evaluated with the Periotest device. At the day of surgery, mean mobility was -3.3, while minor changes were observed thereafter: mean values of -3.77, -3.47, and -3.63 were recorded at 3, 6, and 12 months after implant surgery, respectively. Sulcus depth appeared relatively stable after the 3rd month when the implant platform was used as a reference. Recession of 0.43 mm was recorded between the 3rd and 12th month; when the depth of the peri-implant sulcus was measured from the implant platform, 0.1 mm of change was seen between the 3rd and 12th month. Probing depth measurements revealed that 3 months after implant placement, average probing depth was 3.60 mm, while at 12 months it was 3.20 mm. DISCUSSION: The peri-implant soft tissue parameters (bleeding on probing, probing depth, peri-implant soft tissue level), mobility, and marginal bone level appeared to be similar to findings of previous studies regarding the conventional 2-stage loading protocol. CONCLUSION: Results of the current study provided evidence that, under the condition of this investigation, single root-form implants can be immediately loaded when placed in the maxillary premolar area.
Graduate Program in Implant Dentistry, Loma Linda University, California 92350, USA.

Early loading of unsplinted implants supporting mandibular overdentures using a one-stage operative procedure with two different implant systems: a 2-year report.
TAWSE-SMITH A, PAYNE AG, KUMARA R, THOMSON WM.Department of Oral Rehabilitation, School of Dentistry, P.O. Box 647, University of Otago, Dunedin, New Zealand.
Clin Implant Dent Relat Res  2002;4(1):33-42
BACKGROUND: Step-wise reduction in loading protocols is necessary to evaluate early loading of implants with mandibular overdentures. PURPOSE: To compare the success rates of two different dental implant systems following conventional or early loading protocols in patients being rehabilitated with mandibular overdentures. MATERIALS AND METHODS: Forty-eight edentulous participants were randomly allocated to two different implant systems: one with a machined titanium implant surface (Sterioss, Nobel Biocare, Yorba Linda, California, USA) and the other with a roughened titanium surface (Southern Implants, Irene, South Africa). For each system, the participants were further divided into control groups, in whom mandibular implant overdentures and their respective matrices were inserted following a standard 12-week healing period, and test groups, in whom a 6-week healing period was followed prior to identical loading. Two unsplinted implants to support implant overdentures were placed in the anterior mandible of all participants, using a standardized one-stage surgical procedure. Mobility tests and marginal bone levels, as well as peri-implant parameters, were evaluated at each baseline and 52 and 104 weeks after surgery. RESULTS: There was no statistically significant difference in the success rates of the two systems in either control or test groups. At the 2-year evaluation, a success rate was found of 87.5% and 70.8% for the control and test Sterioss groups, respectively, and 83.3% and 100% for the control and test Southern Implants groups were observed. For the Sterioss groups, eight implants were lost at an early stage: seven in the test group and one in the control group. For the Southern Implants control and test groups, no failures were seen at any time interval. There were no significant differences in marginal bone loss, Periotest values, and peri-implant parameters between implant systems or between any of  the control or test groups. CONCLUSIONS: Early loading, with step-wise reductions in loading protocols, of unsplinted machined Sterioss and roughened Southern Implants fixtures with mandibular overdentures is possible for up to 2 years.

Enhancement of primary stability of dental implants using cortical satellite implants.
ENGELKE W, STAHR S, SCHWARZWALLER W. Department of Oral Surgery, School of Dentistry, Georg-August-University Gottingen, Gottingen, Germany.
Implant Dent  2002;11(1):52-7
PURPOSE: This study aims to assess the effect of satellite implants on the primary stability of dental implants placed in fresh extraction sites in vitro. METHOD: 34 titanium screw implants (3.75 mm x 10 mm; Bego, Bremen, Germany) were inserted in premolar- and molar-fresh extraction sites in domestic pig mandibles. Periotest (PT) values were assessed before and after insertion of one vestibular and one lingual 1.7-mm bone screw (Mondeal, Tuttlingen, Germany) as a satellite implant was connected to the implants with a 0.6-mm microplate welded to the implant abutment. RESULTS: The average PT values were 2.9 without satellite implants, -1.0 with one satellite implant, and -2.5 with two satellite implants during horizontal testing, and 3.0, 1.4, and 0.4, respectively, for vertical testing. CONCLUSION: Satellite implants increase the horizontal stability of implants in fresh extraction sites. Differences for horizontal PT assessment were significant on a 0.01 level of confidence. Implants in extraction sites may be loaded immediately, if vertical stabilization is provided by cortical bone and if horizontal PT values show sufficient stability after satellite implant insertion.

Stability of dental implants in microvascular osseous transplants.
SCHULTES G, GAGGL A, KARCHER H. Department of Oral and Maxillofacial Surgery, University Hospital Graz.
Plast Reconstr Surg  2002 Mar;109(3):916-21
Microvascular iliac crest and scapula transplants have been used in reconstruction of the lower jaw following tumor surgery. It has only been with the insertion of dental implants that a satisfactory prosthetic rehabilitation of the patient has been achieved. For this study, a follow-up of 38 patients with lower jaw tumors was carried out. The patients had been treated with partial resection of the lower jaw and neck dissection with microvascular iliac crest transplants (n = 20) or microvascular scapula transplants (n = 18); this was followed with dental implants (n = 143) in the region of the transplants or the local lower jaw. One hundred thirty-nine of the 143 dental implants were loaded by prosthetic superstructures. In all patients, the implant situation was evaluated on average 2 years 5 months after implantation. Periotest values, periimplant probing depths, and contact bleeding were registered, and the extent of periimplant bone loss was defined radiographically. The clinical situation in the region of the implant was compared for both types of implants and also with the nonresected lower jaw. The average Periotest values were within the normal range for all groups. In one scapula implant, however, a better average of Periotesting, minus sign3.3, was found compared with implants of the iliac crest with Periotest values of minus sign0.7. A measurement of minus sign2.1 was found for the local lower jaw, similar to that of scapula implants. Pathologic probing depths were found for all three compared groups. The radiographically determined vertical loss of bone was the same for all three groups, on average 1 mm at 27 months postoperatively. The highest incidence of sulcus bleeding was found in the scapula implant group. Thus, it can be stated that the scapula transplants provide a similar transplant site to local lower jaw bone, whereas implants in iliac crest transplants show lesser bony stability. Periimplant soft-tissue conditions are worse for both types of transplants compared with local tissue of the lower jaw.

Single-tooth replacement with the Frialit-2 system: a retrospective clinical analysis of 146 implants
Int J Oral Maxillofac Implants 17, 78-85 (2002).
dental implant/Bone Resorption/
PURPOSE: This study was intended to provide a report of experience and results with Frialit-2 implants used for single-tooth replacement. MATERIALS AND METHODS: Over a 7-year period (1994-2000), 146 single-tooth implants (84 maxilla, 62 mandible) were placed in 112 patients (67 females, 45 males; 31.2 +/- 16.4 years). The sites included maxillary anterior teeth (n = 38) as well as the mandibular premolars and molars (n = 57). Ninety-three crowns were cemented and 53 crowns were screw mounted (22 with vertical, 31 with horizontal screws) on standard abutments. The follow-up time varied between 3 and 80 months (35.8 +/- 16.5 months). RESULTS: Two implants (1.4%) were lost, 1 during early loading and the other after 6 years. The most frequent prosthetic complication was isolated crown loosening of cemented crowns requiring recementation of 9 crowns (9.9%). Crowns with vertical screws showed no crown and/or screw loosening. Four crowns (2.8%) were replaced because of ceramic fracture. DISCUSSION: Peri-implant soft tissue condition, bone resorption, and Periotest values indicated satisfactory results. The cumulative implant survival rate during the follow-up period was 97.3%, and that of the crowns 96.4% (total cumulative survival rate 93.7%). CONCLUSIONS: With the low number of abutment screw loosenings (3.5%), the deep internal hexagonal retention compared favorably to external retention methods. The predominant use of long implants (98.4% > or = 13 mm) allowed a favorable implant/crown ratio with the potential for problem-free, long-term results

Peri-implant tissue response of immediately loaded, threaded, HA-coated implants: 1-year results
J Prosthet Dent  87, 173-181 (2002).
dental implant/overdentures/
Statement of Problem. Although high success rates have been reported with immediately loaded implants, the peri-implant tissue response has not been well documented. Purpose. This study evaluated implant success and peri-implant tissue response of immediately loaded, threaded, hydroxyapatite (HA)-coated root-form implants supporting mandibular bar overdentures with opposing conventional maxillary complete dentures in humans. Material and Methods. Five patients (3 men, 2 women; mean age 61 years) each received 4 HA-coated endosseous root-form implants in the interforaminal region in the mandible. The implants were rigidly splinted with a metal framework within 24 hours. The final EDS clip prosthesis was placed 1 to 2 weeks thereafter. The implants and peri-implant tissues were evaluated clinically and radiographically 0, 1, 3, 6, and 12 months after prosthesis placement. Data were analyzed with a repeated measures 1-way analysis of variance (P<.05). Results. All implants were stable at the end of the observation period (mean Periotest value = minus sign5.9 plus minus 1.4). No peri-implant radiolucencies were noted, and no implants were lost. The mean marginal bone changes were minus sign0.42 plus minus 0.34, minus sign0.84 plus minus 0.55, minus sign1.14 plus minus 0.80, and minus sign1.16 plus minus 0.89 mm at the 1-, 3-, 6-, and 12-month follow-ups, respectively (P<.001). Significant declines in the rates of marginal bone changes at each time interval were noted (P<.001). In addition, there were significant decreases in probing depth (P<.001) and plaque index (P<.001) but no significant difference in the frequency of bleeding upon probing (P=.64). Conclusion. Within the limitations of this study, the peri-implant tissue response of immediately loaded, HA-coated implants was favorable and comparable to that of conventional, delayed-loaded implants after 1 year

Implant-retained mandibular overdentures with Branemark System MKII implants: a prospective comparative study between delayed and immediate loading
Int J Oral Maxillofac Implants 16, 537-546 (2001).
Bone Resorption/radiography/Dental Implantation/Dental Plaque Index/Dental Prosthesis/Denture,Overlay/Osseointegration/
This study was designed to compare the results of immediate and delayed loading of implants with implant-retained mandibular overdentures. Ten patients (test group) received 40 Branemark System MKII implants (4 per patient) placed in the interforaminal area of the mandible. Standard abutments were immediately screwed to the implants, rigidly connected with a bar, and immediately loaded with an overdenture. Ten patients (control group) received the same type and number of implants in the same area, but the implants were left to heal submerged. Four to 8 months later, standard abutments were screwed to the implants and the same prosthetic procedure was applied. Each implant was evaluated at the time of prosthetic loading and at 6, 12, and 24 months after the initial prosthetic load with the following parameters: modified Plaque Index (MPI), modified Bleeding Index (MBI), probing depth (PD), and Periotest. Peri-implant bone resorption was evaluated on panoramic radiographs taken 12 and 24 months after initial prosthetic loading. No significant differences were found between the 2 groups regarding MPI, MBI, Periotest, peri-implant bone resorption, and PD at 6 and 24 months (P > .05). The only difference was found regarding PD values on the mesial and lingual sites at 12 months (P < .05). The cumulative success rate of implants was 97.5% in both groups. Results from this study showed that immediate loading of endosseous implants rigidly connected with a U-shaped bar does not seem to have any detrimental effect on osseointegration. Conversely, this method significantly shortens the duration of treatment with relevant satisfaction for the patients

Stabilitat dentaler Implantate in mikrovaskularen Skapula- und Beckenkammtransplantaten. Vergleichsstudie.
[Stability of dental implants in microvascular scapula and iliac crest transplants]
Mund Kiefer Gesichtschir 5, 293-298 (2001).
Alveoloplasty/Bone Transplantation/Dental Implantation/Mandibular Neoplasms/Scapula/
STUDY: In this study 24 patients with tumours of the mandible, mandibular resection, neck dissection and reconstruction by microvascular iliac crest (13) or scapula transplants (11) were examined following implantological treatment. RESULTS: In all patients the implantological examination was performed on average two years and five months after implant insertion. This allowed for observation of periotest values, periimplant probing depth and sulcus bleeding (SBI). Furthermore, the loss of periimplant bone was registered radiologically. In both groups periotest values were normal. In the group with scapular transplants the mean periotest value was -3.2 and in the other group -0.8. Pathological probing depth was registered in both groups and sulcus bleeding was similar. The loss of periimplant crestal bone was similar in both groups, too. DISCUSSION: It can thus be concluded that perimimplant conditions were equal in both groups two years after implant loading. The stability of implants in scapula transplants was higher than in iliac crest transplants

Clinical experiences with a new maintenance-free shock absorbing element in titanium implants
Implant Dent 10, 246-253 (2001).
Dental Abutments/Dental Implantation/Gingival Hemorrhage/Kinetics/Periodontal Pocket/Statistics/Stress,Mechanical/
Until now, the biokinetic elements of one implant system were to be substituted once a year in order to prevent complications of fractures of fixation screws. In this article a new implant with a maintenance-free shock absorbing element was examined. During the last 6 years, 384 dental implants with a biokinetic element (mobile-implant, SIS Inc., Klagenfurt, Austria) were placed in 138 patients. The implants were loaded with prosthetic superstructures 4 months after implantation. For comparison, 160 patients were treated with 494 conventional titanium implants of the same design without biokinetic elements. All patients were examined radiologically and clinically. Periimplant probing depth, periimplant bleeding, Periotest-values (Siemens, Bensheim, Germany) at the time of prosthetic treatment and 3, 6, 9, 12, and 24 months after implant loading were registered. Implantation was successful in 97.2% of mobile-implants and 98% of conventional implants. There was a low degree of sulcus bleeding and high degree of physiological periimplant probing depths in both patients groups. In mobile-implants, the Periotest-values were positive and similar to that of the control. There was no difference between the values in the maxilla and mandible. In the group with conventional implants, the Periotest-values were negative and showed a low degree of negativity during the first 12 months after implant loading. Periotest-values in the upper jaw were higher than in the lower jaw. There was a lower degree of periimplant bone loss after implant loading in patients with mobile-implants. In conclusion, mobile-implants demonstrate the positive effects of implants with shock absorbing elements. They are maintenance free

Branemark System and ITI Dental Implant System for treatment of mandibular edentulism. A comparative randomized study: 3-year follow-up
Clin Oral Implants Res 12, 450-461 (2001).
Bone Resorption//Dental Abutments/Dental Implantation/Dental Plaque/Dental Restoration/Gingival Hemorrhage/Osseointegration/Periodontal Pocket/
In a randomized prospective study, two implant systems were compared in forty consecutive patients treated for mandibular edentulism. The patients were randomly allotted for treatment by the Branemark two-stage (submerged) system (BRS), or the ITI(R) one-stage (non-submerged) system. In all, 102 Branemark selftapping implants and 106 ITI hollow screw implants were installed and all patients were treated with full bridges. Biological and prosthodontic parameters, complications, success rates, clinical efficacy, patient satisfaction and resource requirements were evaluated. No differences were found in plaque accumulation, bleeding or complications during the follow-up period. The BRS group showed deeper periimplant sulcus, less attached mucosa, larger bridge-mucosa distance and higher Periotest values. Prosthetic complications were not related to the configuration of the implant systems. After 3 years, the cumulative success rates were 97.9% and 96.8% for the Branemark and ITI systems, respectively (difference not statistically significant). One implant in the BRS group had failed to osseointegrate at the time of abutment connection, and another was lost after 2 years due to progressive breakdown of bone. In the ITI group, three implants showed progressive bone loss after 1-3 years associated with periimplant infection. All 40 bridges were intact and remained stable throughout the study. There was general patient satisfaction, but about half the Branemark patients reported difficulty in coping with the surgical procedures. Treatment time was similar for the two systems. It is concluded that both systems meet the current requirements for dental implant systems in the treatment of mandibular edentulism

Comparison of a new dental trauma splint device (TTS) with three commonly used splinting techniques
Dent Traumatol 17, 266-274 (2001).
Dental Debonding/Dental Plaque Index/Oral Hygiene/Orthodontic Brackets/Orthodontic Wires/Periodontal Pocket/Tooth Injuries/Tooth Mobility/Tooth Replantation/
Splinting is the standard of care for stabilization of replanted or repositioned permanent teeth following trauma. The present experimental study compared four dental trauma splints in 10 volunteers. The evaluated splints included a wire-composite splint (WCS), a button-bracket splint (BS), a resin splint (RS), and a new device (TTS=Titanium Trauma Splint) specifically developed for splinting traumatized teeth. All splints were bonded to the labial surfaces of the maxillary lateral and central incisors. Splints were left in place for 1 week. After splint removal, the next splint was placed after a 1-week rest period. The sequence of splint application was randomized for each individual. The following parameters were assessed: tooth mobility with horizontal and vertical Periotest values (PTV) before and after splint application and splint removal, respectively; probing depths, plaque and bleeding on probing indices before splint application and removal, and chair time needed for splint application and removal. After splint application, horizontal PTV were significantly lower in central incisors for BS compared to TTS (P=0.04), and for RS compared to TTS (P=0.005) and to WCS (P=0.006). Reduction of lateral tooth mobility (=splint effect) expressed by the difference between horizontal pre- and postoperative PTV was significantly greater in RS compared to TTS and WCS (P<0.05) for central as well as for lateral incisors. However, changes of vertical tooth mobility were not significant across the splinting techniques. Periodontal parameters remained unchanged, reflecting the excellent oral hygiene by the study subjects. The chair time needed for splint application was significantly shorter for TTS (P<0.01). In conclusion, all tested splints appeared to maintain physiologic vertical and horizontal tooth mobility. However, the latter was critically reduced in RS splints

Comparison of incisor mobility after insertion of canine-to-canine lingual retainers bonded to two or to six teeth. A clinical study
J Orofac Orthop  62, 387-396 (2001).
Dental Bonding/Orthodontic Retainers/Orthodontic Wires/Tooth Mobility/mobility/therapy/
BACKGROUND: Fixed appliance therapy often extends over several years. Debonding is warmly welcomed and is often seen by the patient as the end of treatment. Yet both patients and parents often underestimate the importance of the subsequent retention period and the speed at which negligence in this treatment phase results in relapse. Bonded retainers guarantee excellent long-term stability at least while they are in situ. The reliable attachment of lingual retainers with modern bonding techniques has led to widespread application of this retention method. The present study investigated its influence on tooth mobility and on the damping properties of the periodontal tissue, by means of a dynamic measuring method (Periotest). PATIENTS AND METHOD: For this purpose two groups with mandibular bonded retainers and one control group were formed. The control group wore removable retention appliances. In all groups, active treatment with fixed appliances had been completed at least half a year before baseline. RESULTS: The results showed that bonded retainers had a negative impact on the damping properties of the periodontal tissue and thus in the broader sense on tooth mobility. Tooth mobility decreased with the number of teeth to which the retainer was bonded but remained, as in the control group, within the physiologic range

Tilted implants as an alternative to maxillary sinus grafting: a clinical, radiologic, and periotest study
Clin Implant Dent Relat Res 3, 39-49 (2001).
Alveolar Ridge Augmentation/Bone Resorption/surgery/Dental Implantation/Follow-Up  Studies/Human/Maxillary Sinus/branemark
BACKGROUND: Owing to mechanical and anatomic difficulties, implant treatment in the atrophic maxilla represents a challenge. The maxillary sinus floor augmentation procedure is still not universally accepted because of its complexity and its unpredictability. PURPOSE: In this study, a combination of tilted and axial implants was used in patients with severely resorbed posterior maxillae as an alternative to sinus grafting. MATERIALS AND METHODS: Twenty-five patients were rehabilitated with 29 fixed partial prostheses supported by 101 Branemark System implants. Fifty-nine implants were installed in an axial and 42 in a tilted direction. The average follow-up period was 37 months (range: 21-87 mo post loading). RESULTS: After 5 years, the implant cumulative success rate was 95.2% (survival: rate 100%) for the tilted implants and 91.3% (survival rate: 96.5%) for the axial implants, and the prosthesis survival rate was 100%. At the fifth year, the average marginal bone loss was 1.21 mm for the tilted implants and 0.92 mm for the axial ones. The mean Periotest values (PTV) at loading time were -2.62 and -3.57, and after 5 years the PTVs were -4.73 and -5.00 for the tilted and the axial implants, respectively. During the follow-up, all prostheses but two were mechanically stable, retightening of 18 abutment screws and of 5 gold screws in 14 prostheses was done, and fracture of two abutment screws and two occlusal surfaces was experienced. CONCLUSIONS: Results indicate that the use of tilted implants is an effective and safe alternative to maxillary sinus floor augmentation procedures

Influence of the implant abutment on the Periotest value - a study done in vivo
[Einfluß des Implantataufbaus auf den Periotestwert - eine in vivo Untersuchung]
Quint.Int. 32, 797-799 (2001)
implant; dental implants; Crowns; Frialit2; Gingiva; Percussion; mobility; prosthetic restoration; implant-bone-interface; renewal of prosthesis
Objective: Results of Periotest measurements for dental implants depend on the type of prosthetic abutment utilized for the restoration. In case the Periotest values cannot be measured at the single crowns because of the indication, the Periotest values depending on the type of superstructure must be considered for comparison. Method and materials: for The present study fifty-nine patients were selected from regular follow-up program. The Periotest values of Frialit-2 implants were measured at the gingiva former and abutment, at the end of the healing period. The values were then compared with to the Periotest measurements at the stage of the final single crown's insertion and evaluated during the first follow-up examination. Results: Compared to values measured at single crowns, the Periotest value measured at gingiva formers decreased in average by –3.5. The measurement of the abutment revealed a decrease of –1.7. Until the first recall and under functional loading of implants, the Periotest value increased in average by +1.8. These divergences significantly differ from zero. Conclusion:  If measurements at different abutments like crown abutment or single crown are inevitable, correction of the Periotest values by means of the given mean values leads to more precise results. It is recommended to perform Periotest measurements for the first and subsequent prostheses, during all prosthetic stages to allow comparison if some parts of the prosthetic abutment have to be changed.
Zusammenfassung. Das Ergebnis der Periotestmessung bei dentalen Implantaten hängt ab von der Art des prothetischen Aufbaus. Kann abhängig von der Indikation der Periotestwert nicht an einer Einzelkrone gemessen werden, so muß die Abhängigkeit des Periotestwertes von der Suprakonstruktion berücksichtigt werden um vergleichbar zu sein. Dazu wurde in der vorgelegten Arbeit bei Frialit®-2 Implantaten am Ende ihrer Einheilzeit der Periotestwert am Gingivaformer und am Aufbau gemessen und mit der Periotestmessung an einer Einzelkrone implantat-indiviuell verglichen. Zusätzlich wurde der Periotestwert bei der ersten Nachkonrolle ausgewertet. Im Vergleich zur Einzelkrone verringert sich der Periotestwert gemessen am Gingivaformer im Mittel um-3,5. Bei der Messung am Aufbau sinkt der Periotestwert um -1,7. Bis zur ersten Nachkontrolle, während funktioneller Belastung der Implantate, erhöht sich der Periotestwert im Mittel um +1,8. Diese Unterschiede sind hochsignifikant verschieden von Null. call for reprints

Bewegungsverhalten von Zähnen und dentalen Implantaten bei der Periotestmessung mit Zahnreihenkontakt – eine In-vitro Untersuchung
[Movement of Teeth and Dental Implants on Periotest Measurement in Occlusion – an in vitro Analysis]
Biomed.Technik 46, 311-319 (2001)
Wegmessung, Kraftmessung, Zahnheilkunde, zahnärztliche Implantologie, Periotest, In-vitro, motion measurement, force measurement, dental medicine, oral implants
Zusammenfassung: Erkrankungen des Zahnhalteapparats frühzeitig zu erkennen ist wesentlich für die Planung konservierender, prothetischer und chirurgischer Behandlungen. Die üblichen klinischen Methoden sind überwiegend  subjektiver Art. Das Periotestverfahren wurde vor allem für die Diagnose von Erkrankungen und Veränderungen des Zahnhalteapparats entwickelt. Daneben wird es auch benutzt um die okklusale Adjustierung der Ober- und Unterkieferkauflächen bei neu eingesetzten Gußfüllungen und Kronen zu prüfen. Um diesen Einsatzbereich zu untersuchen sind in einem Kiefermodell mit idealisierten künstlichen Zahnkronen Weg- und Kraftmeßfühler eingebaut. Weg und Kraft werden während der Periotestmessung aufgezeichnet. Die Maximalamplituden in apikaler (senkrechter) Richtung bei rauhen Kauflächen nehmen zu mit anwachsender Belastung durch den Gegenzahn. Dagegen zeigen sie bei glatten Kauflächen keine Abhängigkeit von der okklusalen Belastung. In oraler (waagrechter) Richtung verkleinern sich die Maximalamplituden sowohl bei rauhen als auch bei glatten Kontaktstellen. Bei glatten Kauflächen scheinen die Zahnhöcker so aufeinander zu gleiten, daß die beiden Gegenzähne insgesamt ihren Abstand nicht verändern und  keine zusätzlichen Kräfte in apikaler Richtung entstehen. Bei rauhen Kauflächen entstehen zusätzliche Kräfte und verfälschen die Periotestmessung.
Abstract: An early diagnosis of periodontal lesion is essential for planning of restorative, prosthetic and surgical treatment. Usual clinical methods are predominantly subjective techniques. The Periotest device is an instrument specially developed for the diagnosis of periodontal diseases. Periotest is also used für control of occlusal adjustment after insertion of inlays or artificial crowns. In order to investigate this special operation of Periotest a jaw model has been constructed, consisting of motion and force gauges and idealised dental crowns. Motion and force have been recorded while Periotest measurement was done. The maximum values in apical direction got with occlusal contact points not polished increase with growing occlusal load. With polished contact points the maximum values in apical direction reveal no dependence on occlusal load. The maximum values of motion and force in oral direction decrease with increasing occlusal load, both with polished and unpolished occlusal contact points. With polished contact points the occlusal contours of the teeth appear to slide on one another in a way that the distance of the teeth all in all remains unchanged without adding forces in apical direction. Increasing roughness and friction of the contact points lead to additional forces and false Periotest values. call for reprints

Vertical distraction osteogenesis of edentulous ridges for improvement of oral implant positioning: a clinical report of preliminary results
Int.J.Oral Maxillofac.Implants.  16, 43-51 (2001).
This study examined the opportunities offered by intraoral distraction osteogenesis to vertically elongate insufficient alveolar ridges and thereby improve local anatomy for ideal implant placement. Eight patients presenting with vertically deficient edentulous ridges were treated by means of the distraction osteogenesis principle with an intraoral alveolar distractor. Two to 3 months after consolidation of the distracted segments, 26 implants were placed in the distracted areas. Four to 6 months later, abutments were connected and prosthetic loading of the implants was started. The mean follow-up after initial prosthetic loading was 14 months. In all patients, the desired bone gain was reached at the end of distraction (mean vertical bone gain of 8.5 mm). Probing depth, Bleeding Index, and Plaque Index around implants were evaluated, and Periotest values were also calculated. The cumulative success rate of implants was 100%. Radiographic examinations 12 months after functional loading of implants showed a significant increase in the density of the newly generated bone in the distracted areas. This technique seems to be reliable, and the regenerated bone has withstood the functional demands of implant loading. Success rates of implants, periodontal indices of peri-implant soft tissues, and Periotest values were consistent with those reported in the literature regarding implants placed in native bone.

Diagnosing increased muscle activity and occlusal stress in temporo mandibular joint syndrome with Periotest.
Online. 2001-VII-30.
Periotest measurements were carried out not in occlusal contact to the antagonist tooth and under maximum habitual occlusion in 38 patients with functional temporo mandibular joint syndrome and in a control group of 25 test subjects with periodontally sound dentition. A comparison between the patients with temporo mandibular joint syndrome and test subjects without muscle findings showed significant (1%) variations both for Periotest measurements not in occlusal contact and particularly for Periotest value differences of the measurement carried out under maximum habitual occlusion and the measurement not in occlusal contact. This was especially true for the premolars and the first molars. In the test subjects without muscle findings, Periotest value differences were between -2.0 and -3.4 (confidence intervals). In patients with muscle findings, the Periotest value differences of 5.4 to 7.9 were greater.
Point-biserial correlation coefficients showed a particularly pronounced correlation between Periotest value differences and sensitivity to pressure in the aductory masticatory muscles.
Bei 38 Patienten mit funktioneller Myoarthropathie und 25 Probanden einer Kontrollgruppe mit parodontal gesundem Gebiß wurden Periotestwerte bestimmt. Die Periotestmessungen wurden sowohl ohne Okklusalkontakt als auch in maximaler Interkuspidation durchgeführt. Der Vergleich der Patienten mit Myoarthropathie und der Probanden ohne Muskelbefund ergab signifikante Unterschiede auf dem  1%.Niveau sowohl bei Periotestwerten ohne Okklusalkontakt als auch vor allem bei den Differenzen der Periotestwerte ohne Okklusalkontakt und der Periotestwerte in maximaler Interkuspidation. Dies betraf vor allem die Prämolaren und die ersten Molaren. Bei Probanden ohne Muskelbefund ergaben sich Periotestwertdifferenzen zwischen -2,0 und -3,4 (Vertrauensbereiche). Bei Patienten mit Muskelbefund waren die Periotestwerte mit -5,4 ... -7,9 ausgeprägter negativ.
Punktbiserielle Korrelationskoeffizienten ergaben einen besonders ausgeprägten Zusammenhang zwischen Periotestwertdifferenzen und der Aktivität der aduktorischen Kaumuskulatur.

Periotest values and occlusion.
Online. 2001VIII-7.
Periotest / Trauma / Alveolar Bone Loss / occlusal trauma / clinical arameters / Tooth / parodontitis / rezession / papillen-blutungsindex / Papillenblutungsindex / knochenabbau
Numerous experiments have been carried out in order to identify occlusal trauma as an etiologic factor in the pathogenesis of periodontopathies. With Periotest ( an instrument is available to quantify occlusal overstressing. In 905 teeth and 43 patients with periodontitis the Periotest values were determined without occlusal contact and under maximum habitual occlusion. Clinical parameters like probing depth, recession, papillary bleeding index, bone resorption and qualitative such as tipped tooth, filling, abrasion facets in the occlusal areas and eccentric abrasion facets were evaluated. Bone resorption was determined based on intraoral radiographs. Multiple linear regression calculations between standard Periotest values (Periotest value without tooth contact) or Periotest value differences (the difference between Periotest values under maximum habitual occlusion and without occlusal contact) as dependent variables and the quantitative parameters as independent variables resulted in determination coefficients of 61% for the Periotest value without occlusal contact and 40% for the Periotest value difference. The influence of bone resorption clearly dominated over all other quantitative parameters.
Occlusal parameters as tipped teeth, restorations and abrasion facets were explored in teeth without bone resorption and without pathological pockets. Significantly higher Periotest values and significantly more negative Periotest value differences in tipped teeth were interpreted as a possible source of occlusal trauma. Less negative Periotest value differences in teeth with eccentric abrasion facets indicate reduced intercuspidation. Abrasion facets in the occlusal areas tend to cause higher stressing. Restorations had no effect on Periotest values and Periotest value differences.
Bei 43 Patienten mit marginaler Parodontitis wurden an 905 Zähnen die Perio-testwerte ohne Okklusion und in maximaler Interkuspidation ermittelt. An klini-schen Be-funden wurden die quantitativ meßbaren Parameter Tiefe der Sulcus-taschen, Re-zession, Papillen-blutungsindex, Knochenabbau und die qualitati-ven Merkmale Kip-pung, Füllung, Schliffflächen im Okklusionsfeld und exzentri-sche Schliffflächen erho-ben. Der Knochenabbau wurde durch Ausmessen von Mundfilmen be-stimmt. Multi-ple lineare Regressionsrechnungen zwischen Periotestwert ohne Okklusion und Differenz der Periotestwerte in maximaler In-ter-kuspidation und ohne Okklusion als abhängigen Variablen und den quanti-tativen Parametern als unab-hängige Variablen ergab Koeffizienten der Deter-mination von 61% für den Pe-riotestwert ohne Okklu-sion und 40% für die Periotestwertdifferenz. Der Einfluß des Knochenabbaus do-minierte deutlich gegenüber dem Einfluß der übrigen quantitativen Parameter. Der Einfluß der traumatischen Parameter Kippung, Füllung und Schliffflächen auf die Regres-sion zwischen Periotestwertdifferenzen und Kno-chenabbau wird dargestellt. Signifikant höhere Periotestwertdifferenzen bei Zahnkippungen bringen ein okklusales Trauma zum Ausdruck. Schliffflächen im Okklusionsfeld haben trau-matische Bedeu-tung. Exzentrische Schliffflächen wirken ebenfalls traumatisie-rend bei parodontal progredient geschädigten Zähnen. Ok-klusionsstörungen können bei bestehender marginaler Parodontitis zu verstärk-tem Knochenab-bau führen.

A comparative clinical investigation of 2 early loaded ITI dental implants supporting an overdenture in the mandible
Int.J.Oral Maxillofac.Implants.  16, 246-251 (2001).
dental implants/implant/Mandible/Titanium/Patient Satisfaction/Survival Rate
The purpose of this prospective clinical study was to evaluate the efficacy of early loading of implants and to provide evidence to support simplified treatment of mandibular edentulism by using an implant designed for 1-stage surgery, combined with ball abutments to circumvent the need for a fixed prosthodontic superstructure. Historically, the recommended time between the placement and functional loading of dental implants has been 3 months in the mandible. This recommendation is the result of a systematically chosen healing time during development of implant treatment. In recent years, histologic and experimental studies have shown that specially designed implants can result in increased bone-to-implant contact at earlier healing times. Accordingly, these implants can be placed into function faster than previously recommended. In this study, 21 patients aged between 61 and 85 years with edentulous mandibles were included. All received 2 titanium plasma-sprayed, solid-screw dental implants in the interforaminal region. Ten patients had the implants loaded with an overdenture connected with ball abutments after 3 months (control group). The other 11 patients (test group) had prostheses connected to the ball abutments after a maximum of 3 weeks. Marginal bone resorption, Periotest values, and patient satisfaction were evaluated. The cumulative post-loading implant survival rate was 100% for both groups after 24 months. Marginal bone resorption after 1 year around all implants ranged from 0 to 2 mm (no significant differences between groups; P < .05). Periotest values for all implants 1 year after loading were below zero (range -1 to -6). The results of this clinical trial suggest that successful early loading of 2 implants is possible provided there is uncomplicated implant placement

References: ... 1989  1990  1991  1992  1993   1994  1995  1996  1997  1998  1999  2000  2001  2002  ...

The effect of splinting of teeth in combination with reconstructive periodontal surgery in humans
Clin.Oral Investig.  4, 98-105 (2000).
Human/Tooth/mobility/Wound Healing
The purpose of this study was to evaluate the effect of splinting teeth on the results of periodontal reconstructive surgery using a specific carbonate bone replacement graft (BRG) material. Forty-five patients were randomly treated with a periodontal surgery approach. Natural coral calcium BRG was utilised in 33 patients. This 33-patient group was divided into three equal groups. In the presplint group, teeth were splinted to at least two rigid teeth before surgery, in the postsplint group, teeth were splinted at suture removal, and in the nonsplint group, the treated teeth were not splinted at all. In 12 patients, teeth were treated with surgical debridement (DEBR) alone and not splinted. Periodontal probing depth (PPD), clinical probing attachment level (CPAL), and tooth mobility were measured using desmodontometry (DDM) and periotest (PTV) with reproducible methods before surgery and at various periods up to 1 year afterwards. A decrease in PPD (5.4 mm, SD 1.4 mm) and tooth mobility (DDM-horizontal 257 microns, SD 60 microns) and a gain of CPAL (5.1 mm, SD 1.4 mm) were seen following the use of BRG in presplint teeth. In the same group, PPD and tooth mobility were significantly reduced compared to nonsplint teeth. DEBR alone showed reductions in tooth mobility and PPD and a significantly smaller gain in CPAL than in presplint teeth treated with BRG. The less favourable improvement in periodontal function of postsplint or nonsplint teeth seemed to be due to the loss of BRG material caused by tooth mobility. These results indicate that an undisturbed wound healing process using BRG together with tooth stability is beneficial to overall clinical success

Externe Wurzelresorptionen nach Zahntrauma: Diagnose, Konsequenzen, Therapie
[External root resorption following tooth trauma: its diagnosis, sequelae and therapy].
Schweiz.Monatsschr.Zahnmed. 110:712-729, 2000.
Zahntrauma, Wurzelresorption, Ankylose
 Diagnostik externer Wurzelresorptionen:
Im Gegensatz zu intraoralen Röntgenaufnahmen ist das Periotest-Verfahren in der Lage, externe Wurzelresorptionen nach Zahntrauma frühzeitig und zuverlässig zu erkennen. Mit dem Periotest-Gerät (Fa. Medizintechnik Gulden, Bensheim, Deutschland) werden die Zähne horizontal durch einen integrierten Stössel definiert perkutiert. Der untersuchte Zahn sollte dabei möglichst vertikal stehen und der Messkopf etwa im rechten Winkel im Abstand zwischen 0,5 mm und 2,5 mm angesetzt werden. Das Gerät misst die Dämpfungseigenschaften des Zahnhalteapparates. Der parodontalen Auslenkung wird ein Wert zugeordnet, der akustisch und optisch wiedergegeben wird. Als Vergleich sind die unverletzten Nachbarzähne zu prüfen, da die vorn Hersteller angegebenen Normwerte eine hohe (interpersonelle) Variabilität aufweisen. Der Normbereich für einen mittleren oberen Schneidezahn liegt beispielsweise zwischen 3 und 13, für einen lateralen Inzisiven zwischen 3 und 10. Grössere Messwerte lassen auf eine entzündlich erhöhte oder traumatisch bedingte Zahnlockerung schliessen. Kleinere Periotest-Werte beschreiben pathologische Verengungen des Parodontalspalts, den direkten Kontakt oder die knöcherne Verbindung zwischen Alveotarknochen und Zahn: die Ankylose. Pro Zahn sollten 2-3 Messungen durchgeführt werden. Erforderlich für die Diagnostik von Wurzelresorptionen ist eine Verlaufskontrolle. Daher sollten bei jeder der zunächst engmaschigen posttraumatischen Kontrollen Periotest-Werte erhoben werden. Resorptionsbedingte Veränderungen der Messwerte werden dadurch sicher und schnell erkannt. Wichtig ist auch, dass die Anwendung des Periotest-Gerätes nach den Herstellerangaben erfolgt, um re- produzierbare Werte zu erhalten.
Erfahrungen zeigen, dass vertikal gemessene Periotest-Werte noch früher Hinweise auf eine beginnende externe Wurzelresorption geben (Flachlagerung des Patienten, Zahnachse möglichst parallel zum Boden und Ansatz des Messkopfes axial) (EBELESEDER & GLOCKNER 1999). ....

Klinische und apparative Diagnostik iatrogener parodontaler Schädigungen - .....
Univ. Tübingen. Medizin. Diss. 2000.

Clinical outcomes of three Parkinson's disease patients treated with mandibular implant overdentures
Clin.Oral Impl.Res. 11, 566-571 (2000).
overdentures/dental implants/
Parkinson's disease (PD) often affects the oro pharyngeal musculature, leading to problems with speaking, chewing and swallowing. The inevitable reduction in food and fluid intake contributes to the further deterioration of neurological symptoms. Parkinson's disease patients have great difficulties in adjusting to the use of complete dentures. It is the purpose of this report to evaluate the benefit of using dental implants combined with overdentures to improve chewing and predigestion capacity in severely handicapped PD patients. Three edentulous PD patients (2 male, 1 Female; mean age 75.7 years; mean PD duration 4.3 years; PD severity grade III according to Hoehn and Yahr; mean edentulousness 19.3 years) complaining of poor chewing ability were included in this evaluation. One-stage dental implants were placed in the interforaminal region of the mandible. After completion of healing, new overdentures were fabricated. Custom-made non-rigid (resilient) telescopic attachments were used for retention of the overdentures on the implants. Follow-up examinations of the 3 patients were made between 28 and 42 months after the completion of treatment, and peri-implant tissue conditions as well as the patients' self-assessed satisfaction level were recorded. A modified gastrointestinal symptoms questionnaire, Hoehn and Yahr Scale and body weight measurements were used to monitor gastrointestinal impairment and PD severity. The peri-implant parameters indicated healthy soft tissue conditions and all Periotest values were in the negative range. The patients judged their chewing abilities to be greatly improved. Since placing the implants, PD severity had deteriorated to grade IV (Hoehn and Yahr scale) in 2 patients and was stable in 1 patient. The body weight had improved slightly in all patients (mean 2.2 kg). On the gastrointestinal scale, all patients had improved from a mean score of 8.7 to 5.7. Non-rigid telescopic attachments for overdenture stabilization are particularly suitable for PD patients as they are easy to handle and to clean. The patients reported remarkable improvement in their chewing ability, an assessment which would seem to be supported by the improved gastro-intestinal index. The regimen described appears to be a useful adjunctive treatment in edentulous Parkinson's disease patients and may be considered for patients with diseases similarly affecting motor skills

Vertical alveolar ridge distraction with prosthetic treatable distracters: A clinical investigation
Int.J.Oral Maxillofac.Impl. 15, 701-710 (2000).
implant/Alveolar Process/Atrophy/Trauma/Tooth/Alveolar Ridge Augmentation/
Alveolar ridge distraction is a recent and promising technique for ridge augmentation. Since 1997, a new distraction system incorporating a distraction implant has been in use. It can be used for alveolar ridge distraction and is not removed from the alveolar ridge. Upon completion of the distraction, it remains in the alveolar process for later prosthetic treatment. Thirty-five patients were treated with distraction implants for the correction of alveolar ridge deficiency. In 10 patients with atrophy of the mandible or maxilla, 16 patients with severe defects of the alveolar process after trauma, and 9 patients with localized alveolar ridge defects after single tooth loss, alveolar ridge distraction was carried out with the aid of 62 distraction implants. The distraction implants were loaded by, prosthetic superstructures 4 to 6 months after distraction. A clinical and radiologic follow-up was carried out Periotest values were examined, and periimplant bleeding and probing depth were registered prior to prosthetic treatment and 3, 6 and 9 months after implant loading. In 29 patients, distraction was carried out without complications or problems. Two distraction implants were lost In 2 patients distraction was discontinued because of ankylosis of the distraction segment. In 1 patient the alveolar ridge was overcorrected, and another patient experienced a persisting hypoesthesia of the lip. For 5% of the implants, pathologic probing depth of more than 3 mm and sulcus bleeding were registered prior to prosthetic treatment These observations decreased during the next 9 months. Periotest values were normal before the start of prosthetic treatment. There was a decrease in the Periotest values, thus an increase in implant stability, during the following 9 months. It was concluded that alveolar ridge distraction using distraction implants can be a successful technique for alveolar ridge augmentation with a low rate of complication. Acceptable esthetic and functional results can be achieved by this atraumatic technique of surgery and distraction

A prospective study to assess osseointegration of dental endosseous implants with the periotest instrument
Prospective Studies/Osseointegration/endosseous implants/
Long-term studies have documented the successful treatment of edentulous and partially edentulous patients with titanium implants. However, the inability to identify some non-osseointegrated implants before occlusal loading is costly to practitioners and patients. This study followed all patients (n = 40) who had implants placed over a 6-month period. The Periotest instrument was used at Stage II surgery, final impression, prosthesis placement, and 6 and 12 months after occlusal loading to quantify mobility/lack of mobility of implants with conventional 1-piece temporary healing abutments in place. The positive predictive value was 64%. The Periotest instrument was able to identify non-integrated implants only when measured at Stage II surgery and 12 months after occlusal loading, 64% of the time. However, Periotest values recorded at Stage II surgery are not valid predictors of non-osseointegrated implants 12 months post-occlusal loading

nsertion von Frialit-2-Implantaten nach traumatischem Spätverlust der Zähne 11 und 21. Eine Fallbeschreibung.
Quintess. 51 443-450 (2000)
Replantation, Wurzelresorption, Luxationen, Einzelzahnimplantate
Zusammenfassung: Die Replantation ist geeignet, im jugendlichen Alter die Zeit bis zum Abschluß des Kieferwachstums zu überbrücken und dann eine Implantation zu ermöglichen. Es wird über einen Fall einer 16-jährigen Patientin berichtet, die mit zwei Einzelzahnimplantaten in der Oberkieferfront versorgt wurde. Vorausgegangen war eine Luxation der beiden mittleren oberen Frontzähne (11,21) nach einem Schulunfall 1987. Nach 7 Jahren trat an Zahn 21 eine chronisch apikale Parodontitis auf, die trotz Wurzelbehandlung und späterer Wurzelspitzenamputation nach 2 Jahren zum Mißerfolg führte. Gleichzeitig wurde röntgenologisch eine erhebliche Resorption der Wurzel am replantierten Zahn 11 beobachtet. Nach Extraktion der Zähne und Abheilung der Wunden wurden 4 Monate später nach genauer Modellanalyse 2 Frialit-2-Implantate inseriert, die nach weiteren 6 Monaten prothetisch versorgt wurden. Die Implantate konnten ein Jahr danach kontrolliert werden. Sie zeigten einen, im Vergleich zum Meßwert unmittelbar nach der prothetischen Versorgung, unveränderten Periotestwert von -1 und eine Taschentiefe von 2 mm. Die Folgeschäden nach Luxation und Replantation von Zähnen einschließlich der eventuellen möglichen späteren Versorgung mit Implantaten werden diskutiert.

Implant-supported mandibular overdentures retained with ball or bar attachments: A randomized prospective 5-year study
overdentures/dental implants/Survival Rate
Purpose: The aim of the present study was to evaluate the periimplant conditions and the maintenance requirements for implant-supported overdentures in the mandible retained with ball or bar attachments during a 5-year period. Materials and Methods: Twenty-six completely edentulous patients had two Astra Tech dental implants placed in the anterior part of the mandible. The denture attachment system for the patients was chosen randomly by drawing lots. Eleven patients drew the bar attachment system and fifteen patients drew the ball attachment system. Plaque Index, Gingival Index, and probing pocket depth were assessed around each implant. Periotest values were recorded, and periodically identical intraoral radiographs were obtained with a specially designed film-holding device. Results: No implants were lost from baseline to the 5-year registration. The periimplant conditions were very healthy after 5 years. No significant differences of the periimplant variables were recorded between the bar and the ball groups. During the first year of function, significantly more complications/repairs were registered in the bar group than in the ball group. In the following years, no significant differences were registered. The mean frequency of complications/repairs per patient per year was 1.0 in the bar group and 0.6 in the ball group during the 5-year observation period. Conclusion: Two implants with ball or bar attachment supported an overdenture in the mandible for 5 years with a 100% survival rate. No differences in marginal bone loss or health of the periimplant mucosa were observed between bar and ball attachment, but the frequency of technical complications/repairs per patient was higher around bar than ball attachments

Advanced biomaterials used for a new telescopic retainer for removable dentures: ceramic vs. electroplated gold copings: Part II. Clinical effects
Biomaterial/Crowns/implant/sbi/Movement/Osseointegration/Kaplan-Meier/Survival Rate/Oral Hygiene
Telescopic retainers with conical ceramic abutment crowns and electroplated gold copings define a new retainer for removable dentures exhibiting favorable tribological properties that could offer clinical advantages. The objective of this study was to evaluate the clinical effects of this retainer. To do so, a novel treatment modality was developed based on intraoral bonding of the copings to the framework in order to be able to realize, in a clinical setting, the retainer function based on a precision fit. A total of 32 patients wearing 33 dentures (16 mandibular, 17 maxillary; period of risk [months]: minimum = 3; maximum = 58; mean = 27.6), supported by 147 abutments (83 natural teeth, 64 implants) with ceramic abutment crowns (IPS Empress(R) 1, IPS Empress(R) 2, InCeram(R), Procera(R), CerAdapt(R); CeraBase(R)) were followed at 6-month intervals. The ceramic abutment crowns showed low plaque accumulation (mean PI = 17.3%). The gingival tissues around natural abutments were generally free of inflammation; so was the mucosa around the implants (mean SBI = 4.9%). Denture adhesion and occlusion did not change, and there were no rocking movements. The mobility las determined by Periotest(R) of 29 teeth was reduced in a highly significant manner within 6 months (t test, p < 0.001). Osseointegration was preserved for all implants. One abutment loosened. Six Empress(R) 1 ceramic copings failed (93.6% Kaplan-Meier survival rate), and one abutment tooth was lost (99.2% survival rate). All patients reported problem-free handling, no rocking movements, and constant adhesion. The adhesive strength of one denture was too low at insertion. 94% of the patients experienced no problems with oral hygiene. The retainer examined has relevant clinical advantages and meets geriatric requirements for removable dentures. (C) 2000 John Wiley and Sons, Inc

Retrospective analysis of Frialit-2 implants in the augmented sinus
The aim of the present study was to investigate clinical and radiographic data of patients treated with implants in the posterior maxilla in combination with sinus augmentation. Study parameters included Periotest values, radiographic analysis, and survival/success rates up to 5 years. Clinical and radiographic criteria resulted in a success rate of 92.7% for sinus implants. Radiographically, the sinus implants showed a mean coronal bone loss of 0.5 mm at 6 months and 1.2 mm at 48 months. The results showed stable periimplant parameters for sinus implants during the observation period of 5 years. The success rates showed no significant differences regarding different implant-supported treatment options for the posterior maxillary region

Effect of early exposure on the integration of dental implants in the baboon: Part 1 - Clinical findings at uncovering
Int.J.Periodontics.Restorative.Dent. 20, 163-171 (2000).
dental implants/one-stage surgical/two-stage surgical
There has been increased discussion on the advantages of a one- versus a two-stage surgical approach in the placement of dental endosseous implants. This study evaluated the influence of early implant exposure on crestal bone height adjacent to the implant surface and Periotest values at uncovering in the baboon. Forty-eight implants (24 commercially pure titanium, 24 titanium alloy) were placed in maxillary and mandibular posterior sites in 6 baboons. implant exposure was evaluated weekly for 3 weeks after implant placement. The level of bone adjacent to the dental implants was measured at placement from the top of the implant collar to the crest of the bone at the mesial, distal, buccal, and lingual surfaces. The maxillary sites were measured again at a 6-month uncovering, while the mandibular sites were measured at a 3-month uncovering. Periotest readings were also recorded at uncovering. Early implant exposure was more common in the mandible, with the majority occurring by the second week postplacement. There were no significant differences in the crestal bone height changes at uncovering between the pure titanium and alloy implants in either arch. In the maxilla, the changes in crestal bone height were not statistically different between exposed and nonexposed implants at any aspect. In the mandible, the difference in 3-month changes between exposed and nonexposed implants was significant for the distal, buccal, and lingual aspects. The overall percentage of implants with a Periotest reading in the "good" category was greater for the nonexposed sires as compared to exposed sires. The results of this study suggest that the two-stage surgical approach results in a better clinical outcome as compared to the one-stage approach in the baboon model

Reliability of some clinical parameters of evaluation in implant dentistry
J.Oral Rehabil. 27, 211-216 (2000).
Alveolar Bone Loss diagnosis/Alveolar Bone Loss radiography/Dental Plaque Index/Osseointegration/Periodontal Index/dental implants/Human/
Clinical tests that are commonly used to evaluate tissues surrounding natural teeth are also used in implant dentistry. It is unclear if they are equally valid and reflect the condition of the bone surrounding an implant reliably. This study evaluates the use of a plaque index, a gingiva index, the assessment of a probing depth and the Periotest value and relates the findings to the image on a radiograph in 16 patients, involving 32 IMZ implants. All four clinical tests showed poor sensitivity and, in general, only fair specificity when observations from the image on the radiograph were interpreted as the 'golden standard' for the presence or absence of pathology adjacent to the implant. Frequently, based on any clinical parameter, disease was not diagnosed, while the radiograph did show pathological loss of bone at the bone-implant contact area. It is concluded that the aforementioned parameters are unreliable and unfit for clinical evaluation in implant dentistry. Radiographs are needed to evaluate critical marginal bone changes surrounding dental implants

Long-term follow-up of maxillary incisors with severe apical root resorption
Eur.J.Orthod. 22, 85-92 (2000).
Alveolar Bone Loss/Odontometry/Periodontal Index/Radiography/Tooth Mobility diagnosis/Human/Periotest
The purpose of the study was to analyse the mobility of teeth with severe orthodontically induced root resorption, at follow-up several years after active treatment, and to evaluate mobility in relation to root length and alveolar bone support. Seventy-three maxillary incisors were examined in 20 patients, 10-15 years after active treatment in 13 patients (age 24-32 years) and 5-10 years after active treatment in seven patients (age 20-25 years). All had worn fixed or removable retainers; seven still had bonded twistflex retainers. Total root length and intra-alveolar root length were measured on intra-oral radiographs. Tooth mobility was assessed clinically according to Miller's Index (0-4) and the Periotest method. Crestal alveolar bone level, periodontal pocket depth, gingival, and plaque indices, occlusal contacts during occlusion and function, and dental wear were recorded. There was a significant correlation (P < 0.05) between tooth mobility, and total root length and intra-alveolar root length. No correlation was found between tooth mobility and retention with twistflex retainers. None of the variables for assessment of periodontal status, occlusion and function were related to total root length or tooth mobility. It is concluded that there is a risk of tooth mobility in a maxillary incisor that undergoes severe root resorption during orthodontic treatment, if the remaining total root length is < or = 9 mm. The risk is less if the remaining root length is > 9 mm. Follow-up of teeth with severe orthodontically induced root resorption is indicated.

The fate of osseointegrated implants in patients following oral cancer surgery and mandibular reconstruction
Head.Neck 22, 111-119 (2000).
Dental Implants/Mandibular Prosthesis/Tissue Transplantation/Osseointegration/Germany
BACKGROUND: The feasibility of implant treatment in patients after oral ablative tumor surgery and defect reconstruction has not yet been investigated in terms of the requisite high standards of success assessment. A report on this topic must address not only implant survival but implant health, bone response, soft tissue health, failure pattern, and time of failure, as well.
METHODS: From June 1990 through December 1997, 90 patients received 320 dental implants after oral tumor resection and immediate soft tissue reconstruction. Included in the study were 45 patients with 162 implants loaded for at least 1 year. Regular follow-up for 6 years consisted of detailed medical history and evaluation of periodontal parameters. Out of this population, 10 vascularized iliac bone grafts for mandibular reconstruction containing loaded implants were selectively evaluated for bone loss.
RESULTS: The assessment of pocket probing depths, plaque accumulation, bleeding disposition, implant mobility by means of the Periotest method applied to the restoration type, horizontal and vertical (peri-implant) bone loss according to x-ray findings, causes and time of implant loss, and subjective statements offered results comparable to those found in healthy subjects examined with periodontal success parameters.
CONCLUSION: Prosthetic restoration of patients after oral ablative tumor surgery followed by hard and soft tissue reconstruction can be achieved with dental implants with similar long-term efficacy as found in healthy subjects adhering to internationally established requirements. (C) 2000 John Wiley and Sons, Inc

Long-term follow-up of maxillary incisors with severe apical root resorption
Eur.J.Orthod. 22, 85-92 (2000).
Alveolar Bone Loss/Odontometry/Periodontal Index/Radiography/Tooth Mobility diagnosis/Human/Periotest
The purpose of the study was to analyse the mobility of teeth with severe orthodontically induced root resorption, at follow-up several years after active treatment, and to evaluate mobility in relation to root length and alveolar bone support. Seventy-three maxillary incisors were examined in 20 patients, 10-15 years after active treatment in 13 patients (age 24-32 years) and 5-10 years after active treatment in seven patients (age 20-25 years). All had worn fixed or removable retainers; seven still had bonded twistflex retainers. Total root length and intra-alveolar root length were measured on intra-oral radiographs. Tooth mobility was assessed clinically according to Miller's Index (0-4) and the Periotest method. Crestal alveolar bone level, periodontal pocket depth, gingival, and plaque indices, occlusal contacts during occlusion and function, and dental wear were recorded. There was a significant correlation (P < 0.05) between tooth mobility, and total root length and intra-alveolar root length. No correlation was found between tooth mobility and retention with twistflex retainers. None of the variables for assessment of periodontal status, occlusion and function were related to total root length or tooth mobility. It is concluded that there is a risk of tooth mobility in a maxillary incisor that undergoes severe root resorption during orthodontic treatment, if the remaining total root length is < or = 9 mm. The risk is less if the remaining root length is > 9 mm. Follow-up of teeth with severe orthodontically induced root resorption is indicated.

Periodontal healing after intentional auto-alloplastic reimplantation of injured immature upper front teeth
J.Clin.Periodontol. 27, 198-204 (2000).
Aluminum Oxide/Ankylosis etiology/Ceramics/Child/Dental Implantation/Tooth Replantation/Germany
BACKGROUND/AIMS: Conventional endodontic treatment results in high complication quota when performed in immature teeth. Intentional reimplantation with extraoral insertion of an endodontic implant (auto-alloplastic reimplantation) is an alternative.
METHOD: In a retrospective study, the healing of 40 teeth reimplanted intentionally according to this method in patients aged 7 to 15 years was evaluated. Clinical tests (palpation, percussion sound, periotest values) and radiographical examinations were used to determine the type of periodontal healing (inflammatory resorption/periodontitis apicalis; replacement resorption/ankylosis; normal healing).
RESULTS: Mean lifetime of the replanted teeth was 59.2+/-42.5 months, estimated survival time on the basis of the Kaplan-Meier analysis was 99.5 months. 17 teeth (42.5%) were classified as failures, mostly due to inflammatory resorption or periodontitis apicalis. Further investigations demonstrated that success rate and retention period of intentionally replanted teeth depend on the preoperative condition of the pulp. Teeth with preoperative infection suffered frequently from inflammatory resorption or periodontitis apicalis after being replanted (14 of 28 teeth). Estimated survival time according to Kaplan-Meier was 75.5 months. In contrast, inflammations or progressive resorptions were not observed in teeth without preoperative infection of the pulp. All these 12 teeth showed normal periodontal healing and regular tooth mobility. In the absence of any pathology in clinical or radiological findings after an average functional period of 72.3 months, the prognosis can be presumed excellent. Estimated survival time of 148.3 months according to Kaplan-Meier differs significantly from survival time of teeth infected preoperatively.
CONCLUSIONS: From the results of this investigation, it may be concluded that an infection of the pulp - due to delay of treatment or attempts at endodontic therapy - should be avoided before intentional replantation of immature front teeth with pulp necrosis. Periodontal healing of the autologous root is not impaired by the insertion of posts made of Al2O3-ceramics or titanium. The inserted posts do not ankylose. Orthodontic movement of auto-alloplastically replanted teeth is possible

References:  ... 1989 1990    1991 1992    1993 1994    1995 1996    1997 1998    1999 2000    2001 2002    ...

Evaluation of the implant master cast by means of the Periotest method
Implant.Dent. 8, 133-140 (1999).
Dental Implantation/Osseointegration/Periotest/
Accurate master casts are essential for the construction of implant-supported prostheses with a precision of fit. The stability of the abutment replicas in the master cast is critical in the accurate reproduction of the patient's oral presentation. The Periotest method is an objective method of quantifying mobility in a tooth and implant. Eighteen gypsum implant master casts containing two brass abutment replicas per cast were evaluated. The abutment replicas were measured three times each for a total of 108 measurements. The mean periotest values and standard deviations were calculated for the master casts and the abutment replicas. The abutment replicas displayed mean periotest values that ranged from +1.3 to -8.0. The study shows that there are significant differences between stable and unstable implant master casts (P = 0.0001, ANOVA-Fisher's protected least significant difference) and abutment replicas (P = 0.0001, Contrast test). The Periotest method will quantify differences in gypsum stone implant master casts as well as the prosthesis supporting brass abutment replicas that are an integral part of the master cast

Measuring abutment/implant joint integrity with the periotest instrument
Int.J.Oral Maxillofac.Impl. 14, 681-688 (1999).
abutment/implant interface/Periotest/abutment screw loosening/implant/tensile preload
Maintenance of the integrity of the abutment/implant interface is essential and is dependent on the abutment screw retaining a preload. Evaluation of this joint is usually done by manual assessment. The purpose of the current study was to determine whether the Periotest instrument could be used to evaluate abutment screw loosening. A custom-designed apparatus was constructed to measure abutment screw loosening. Abutment screws were torqued to 10, 20, 32, and 45 Ncm and then loosened. Objective assessment of screw loosening was carried out with the Periotest device. Subjective evaluation was done by 3 experienced clinicians. The Periotest was found to be more sensitive than manual detection of abutrnent screw loosening. With a change of 2 in the Periotest value, it was found that the tensile
preload in the joint was lost. While the Periotest was more sensitive than manual evaluation, the instrument was not sensitive enough to indicate deterioration of abutment screw loosening prior to loss of tensile preload.
Reprint requests. Dr M. Gary Faulkner, Department of Mechanical Engineering, University of Alberta, Edmonton, Alberta T6G 2G8 Canada. Fax: (780) 492-2200.

Objective Evaluation of Tooth luxation by use of the Periotest Technique
[Objektive Beurteilung intubationsbedingter Zahnlockerungen mit Hilfe der Periotest-Untersuchung]
J. HOFFMANN, A.K. HÄNSSLER, A. Eckart, G. ALFTER, D. LUKAS, S. REINERT (Klinik und Poliklinik für Mund-, Kiefer- und Gesichtschirurgie )
Med Biol Eng Comput, 37 (2), 370-371 (1999) call for reprints
Tooth, intubation, mobility
The hazards of damage to teeth and their periodontal attachment during tracheal intubation are well known to all anesthesiologists. In order to predict the possible risk of perianesthetic iatrogenic risk of tooth luxation we evaluated the use of a measuring method (Periotest ®), normally used for the diagnosis of periodontal disease.We compared the amount of tooth mobility before and after general anesthesia to different scores assessing the difficulty of tracheal intubation. The Periotest method showed to be an objective method to evaluate and document the amount of preexisting tooth loosening and to predict a potential risk of avulsion.
Die Verletzung von Zähnen durch die endotracheale Intubation ist eine häufige Komplikation, in den meisten Fällen wird jedoch eine parodontale Vorschädigung der betroffenen Zähne festgestellt. Nach Literaturangaben hat die Kronen- oder Wurzelfraktur den größten Anteil (44,8%) an diesen iatrogenen Verletzungen. Eine Luxation (21,2%) bzw. traumatische Eluxation (18,9%) der Frontzähne tritt zwar seltener auf, ist jedoch meist folgenschwerer und zunehmend Anlaß für Schadensersatzklagen gegen den behandelnden Anästhesisten. Es ist daher unerläßlich, daß, zumindest bei Risikopatienten, im Rahmen der Prämedikationsvisite eine gründliche Beurteilung des Zahnstatus erfolgt.
Mit unserer Untersuchung stellen wir die Ergebnisse der Evaluation des von einer inderdisziplinären Arbeitsgruppe in Zusammenarbeit mit unserer Klinik entwickelten Periotestgerätes vor, welches auch dem zahnmedizinisch nicht ausgebildeten Ärzten eine objektive Beurteilung gefährdeter Zähne erlaubt. Mit dem Periotestwert beurteilten wir bei 100 Patienten die Zahnlockerung der Front-, Eckzahn- und Prämolarenregion vor und sechs Stunden nach einer Intubationsnarkose. Ein Zahntrauma durch den operativen Eingriff wurde ausgeschlossen. In allen Fällen führten wir eine Taschentiefenmessung durch, die objektive Beurteilung der Intubationsschwierigkeit erfolgte durch Bestimmung der Mallampati und Wilson Scores, des thyreomentalen Abstands sowie eine subjektive Einschätzung des intubierenden Anästhesisten. Es erfolgte eine statistische Analyse der Periotestwerte vor und nach der Intubationsnarkose, diese wurde mit dem, nach unterschiedlichen Kriterien beurteilten, Schwierigkeitsgrad der Intubation korreliiert und darüber hinaus mit der Berufserfahrung des behandelnden Anästhesisten in Bezug gesetzt.
Die Ergebnisse im Einzelnen werden demnächst vorgestellt. Das Periotest-Gerät kann wegen seiner handlichen Gestaltung und einfachen Anwendbarkeit auch vom nicht zahnmedizinisch vorgebildeten Anästhesisten eingesetzt werden.

Immediate loading of modular transitional implants: a histologic and histomorphometric study in dogs
Int.J.Periodontics.Restorative.Dent. 19, 343-353 (1999).
Dental Implantation/Dogs/Osseointegration/Animal/Titanium/
Modular Transitional Implants (MTI) are made from pure titanium and are used to support fixed provisional restorations during the osseointegration of definitive implants. This study histologically examined the jaw response to loaded MTIs in the dog mandible. Three implants were inserted transmucosally into each side of the mandible in 3 dogs. Stability was examined using a Periotest. Anterior and posterior implants were splinted using a cemented acrylic resin fixed partial denture to allow immediate loading. The middle implant remained unloaded and was used as a control. Dogs were sacrificed 11 to 12 weeks after implantation, and tissue blocks containing the implants were removed. Histologic examination showed that 10 of the 18 implants had good bone-to-implant contact, with the percentage of bone contacting the threaded portion of the implant varying from 30% to 65%. There was no statistical difference (p > 0.1) in percentage of bone-to-metal contact between loaded and unloaded implants. Six implants were entirely surrounded by connective tissue with or without inflammation; two implants were lost during the study. The success rate did not differ between loaded and unloaded implants. In the successful implants trabecular bone made good contact with the implant, forming supporting struts. There was bone remodeling in some bone-to-metal contact areas. It is believed that success was mainly influenced by the initial bone density at the implant site and by the uncontrolled load that the animals applied to the implants during the early healing stage.

Experimental study of the damping behaviour of IMZ implants
J.Oral Rehabil. 26, 19-24 (1999).Dental Restoration/Follow Up Studies/dental implants/imz
Measurements of the damping behaviour of dental implants with the Periotest device are considered to be an objective means to assess the mobility of implants. The effects of the position of an implant in the maxilla or mandible, the period of time passing between the measurements and implant placement and the height at which the Periotest measurements are performed on the damping behaviour of implants have been discussed controversially. This experimental study examined the influence of the use of different measuring devices, the measuring height and the embedding depth on the damping behaviour of IMZ implants. The implants were embedded in resin at different depths and damping measurements were carried out at different measuring heights. It was found that the values rose with an increasing measuring height and a decreasing embedding depth. Analysis of variance was used to assess the influence of the embedding depth and revealed that the embedding depth had a significant impact on the measuring values at each measuring height, above 6 mm. Moreover, it was found that the higher the measuring height, the higher the measured values and the greater the differences between the values obtained at the individual depths. The different measuring devices had no influence on the measuring results (P = 0.79). The results of this study suggest that a longitudinal follow-up of the peri-implant residual bone height around individual implants is possible. Single measuring values by themselves do not allow any conclusions about the prognosis of an implant. The assessment of the peri-implant bone height through Periotest measurements is conceivable only when a table of damping values taking into account the physical length of the implant, the embedding depth and the measuring height for the examined implant system is available. In cylindrical implants, the head of the available prefabricated measuring post can be recommended as a constant measuring point for further studies, especially when the results are to be compared with those obtained by other study groups

Orale Rehabilitation von Tumorpatienten mit enossalen Implantaten. Implantationserfolg unter besonderer Berucksichtigung der periimplantaren Gewebe. [Oral rehabilitation of tumor patients with endosseous implants. Implant success with special reference to peri-implant tissue]
Mund Kiefer.Gesichtschir. 3 Suppl 1, S99-105 (1999).
In a prospective study, the influence of the status of the peri-implant hard and soft tissues on the success of enosseous dental implants in tumor patients was assessed. Out of 59 tumor patients with 261 implants, treated between July 1988 and August 1996, a pool of 23 patients with 99 implants provided with dentures for at least 1 year was obtained. Eighteen of these patients suffered from a squamous cell carcinoma of the oral cavity. Seventeen patients underwent preoperative radiation (40 Gy). A total of 68 out of 99 implants were inserted into autologous bone transplanted to reconstruct the mandible. In order to assess the peri-implant hard and soft tissues, the Hygiene Index, the Sulcus Bleeding Index, the Gingiva Index, the pocket-probing depth. the peri-implant bone resorption, and the periotest were used. The results in the tumor patients were compared with the results in a pool of nontumor patients. Tumor patients had significantly worse periimplant parameters than nontumor patients. The peri-implant pocket-probing depth proved to have significant influence on the success rate. The overall success rate was 77.8%

A comparison of 3 different endosseous nonsubmerged implants in edentulous mandibles: a clinical report
Int.J.Oral Maxillofac Implants 14, 543-548 (1999).
Dental Abutments/Dental Implantation/Prognosis/Titanium/Human
The purpose of this prospective clinical study was to investigate the outcome of 3 different types of endosseous, nonsubmerged implants in the anterior part of the mandible. Fourteen older edentulous patients, 10 females and 4 males, were included. All participants received 3 different types of endosseous implants in the anterior mandible: 1 titanium plasma-sprayed cylindric implant (4 mm in diameter), 1 titanium cylindric implant with hydroxyapatite (HA) coating (4 mm in diameter), and 1 standard threaded titanium implant (3.75 mm in diameter). The 3 types of implants were originally designed to be placed in a 2-step surgical procedure. However, at this stage all implants were simultaneously provided with a temporary abutment that penetrated the mucosa. Three months later the temporary abutments were replaced by ball abutments, which were connected to an overdenture. At 12, 24, and 36 months after surgery, marginal bone resorption and Periotest values were recorded. Two patients died within the 2 first postoperative years. Five of 42 implants (11.9%) failed to osseointegrate. After 3 years, marginal bone resorption around titanium plasma-sprayed implants was significantly greater than that seen around both HA-coated and threaded titanium implants. Threaded titanium implants also had significantly better scores for marginal bone resorption than the HA-coated implants. Periotest values for HA-coated cylinders were significantly lower than test values for the other implants after 3 years (P < .05). The conclusion from this investigation is that nonsubmerged implants showed impaired prognoses compared to implants placed according to the 2-stage concept. Marginal bone resorption around titanium plasma-sprayed cylindric implants was clearly increased compared to the 2 other implant systems. Periotest values for HA-coated cylindric implants were superior to titanium plasma-sprayed and pure titanium implant surfaces

A multiparametric analysis of occlusal and periodontal jaw reflex characteristics in adult skeletal mandibular
protrusion before and after orthognathic surgery
J.Oral Rehabil. 26, 686-690 (1999).
Adult/Bite Force/Malocclusion surgery/Percussion/Pressure/Prognathism surgery/Sound diagnostic use/ Tooth Mobility
Periodontal jaw reflex, duration of percussion sounds, tooth mobility, and time-moment analysis of occlusal contacts by the T-scan system were recorded in seven pre-orthognathic surgery patients and six post-orthognathic surgery patients over a 2-year period. The results showed that: (i) reflex response to the pressure applied to the upper right central incisor in the lingolabial direction varied, depending on the background jaw-clenching force (BCF) of the same-sided first molar. The BCF level required to elicit excitatory reflexes was only 0 N (Newton), and inhibitory reflexes were clearly elicited with a BCF of 10 N (1 kgf) and beyond before orthognathic surgery. After orthognathic surgery BCF levels required to elicit excitatory reflexes were 0-40 N (0-4 kgf), and inhibitory reflexes were elicited with a BCF of 60 N(6 kgf) and above; (ii) duration of percussion sounds determined via an occlusal sound analyser decreased in both the upper right central incisor and upper right first molar while tooth mobility measured by 'Periotest(R)' increased in the upper right central incisor, but did not change in the same-sided first molar after orthognathic surgery; (iii) the time moments of occlusal contacts were symmetrical toward the midsagittal axis of the occlusal plane after orthognathic surgery. The centre of the anterioposterior occlusal contacts did not differ between pre- and post-orthognathic surgery groups

Compliant Keeper system replication of the periodontal ligament protective damping function for implants: part II
J.Prosthet.Dent.  81, 404-410 (1999).
Dental Abutments/Dental Prosthesis Design /DentalImplant /Movement
STATEMENT OF PROBLEM: There are numerous articles regarding implant overloading, interfacial integrity and component failure. A significant amount of literature review supports the concept of the progressive loading and damping, and it should be addressed.
PURPOSE: This study was designed to correlate durometer measurements of the elastomeric test materials and actual Periotest values (PTV) of the test materials as preloaded sleeve rings in Compliant Keeper abutments to support the Compliant Keeper as a viable implant damping system.
MATERIAL AND METHODS: A 4-unit fixed-removable implant-supported partial denture was the test model. Sleeve ring combinations replaced "O" rings and 220 Periotest measurements were graphically recorded, then analyzed by least square of means, 2-way analysis of variance, and a Tukey test.
RESULTS: There was a correlation between durometer measurements and Periotest values of sleeve rings. Finite movement was measured accurately with the Periotest (P =. 0001) so that Compliant Keeper systems can be programmed to match the movement of another implant abutment, because they might be able to match the Periotest values of a natural abutment.
CONCLUSIONS: Significant differences exist between the "O" rings and sleeve rings. The sleeve ring, as a controllable damping element, enables the Compliant Keeper system to provide progressive loading and damping for implant-supported prostheses.

Guided bone regeneration with barrier membranes--a clinical and radiographic follow-up study after 24 months
Clin.Oral Implants Res.  10, 16-23 (1999).
Bone Loss/Dental Implants/Osseointegration/Periodontal Index/Bone Regeneration /Guided Tissue Regeneration/Membranes,Artificial/
The present follow-up study evaluated clinical and radiographic parameters of dental implants placed with simultaneous guided bone regeneration with expanded polytetrafluoroethylene (e-PTFE) membranes. All implants were functioning well 24 months after insertion. In all, 63 patients with a total of 91 e-PTFE-augmented implants were integrated in a regular maintenance protocol. Modified periodontal data of 85 implants in 59 patients were recorded at 24 months and indicated no difference to implants placed in sufficient pristine bone. The mean plaque score (mplI) was 0.29, 74% of the sites showed no plaque. The sulcular probing depth ranged from 1 to 7 mm with a mean of 2.6 mm (SD +/- 0.8). Of the sites 96.5% were < or = 4 mm deep, in 49% of them probing resulted in bleeding. Periotest values 6 and 24 months (mean: -3.4 and -3.4) after placement revealed stable peri-implant conditions and sustained osseointegration. The radiographic evaluation performed 6, 12 and 24 months post insertion yielded a mean bone loss of 0.93, 1.36 and 1.51 mm ranging from 0 to 4 mm. The short-term results of our clinical study demonstrated stable peri-implant conditions 2 years after membrane-protected osseous regeneration. The newly formed bone seemed to be able to withstand functional loading in a predictable manner after 18 months.

Peri-implant conditions in periodontally compromised patients following maxillary sinus augmentation. A long-term
Clin.Oral Implants Res.  10, 103-110 (1999).
Alveolar Bone Loss/dental implants/Gingival Recession/Osseointegration/Dental Implantation/Human/branemark/imz/Frialit2
Augmentation of the maxillary sinus in the atrophied edentulous posterior maxilla is an integral part of implant prosthodontics. This study examined the clinical outcome in 50 periodontally compromised successfully treated subjects with severe maxillary atrophy following oral implantation with Branemark, IMZ or Frialit-2 endosseous implants between 1991 and 1994. Simultaneous sinus augmentation was achieved using autogenous bone grafts harvested from the anterior mandible. Oral implants in 37 periodontally healthy patients directly placed in the stable local maxillary bone served as controls. The oral rehabilitation included implant supported restorations or removable superstructures over a period between 3 and 5 years. The peri-implant status of implant abutments inserted in the periodontal compromised augmented maxilla resulted in values comparable to the local maxillary bone except for the GCF rates with enhanced levels of 63.9 +/- 49.9 (controls 37.9 +/- 40.7). The average peri-implant Periotest values in the augmented maxillary sinus (test group) were -3.1 PT and +0.2 PT in the controls. The Periotest scores in the sinus area ranked between -7.0 and +5.0 with mean PT values of -1.5 for IMZ, -3.2 for Branemark and -4.0 for Frialit-2 abutments. The functional integration of oral implants following sinus augmentation with autologous bone grafts and conventionally placed endosseous implants in the local bone was similar. The additional implant stabilization within the mandibular cortical bone grafts resulted in very low Periotest scores. In periodontally compromised subjects treated for chronic adult periodontitis with minimal maxillary bone height less than 5 mm the endosseous implantation with simultaneous sinus augmentation is recommended as an appropriate technique for long-term oral implant rehabilitation.

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update:  2003-X-26.