Investigational Clinical Trial of a Prototype Optoelectronic Computer-Aided Navigation Device for Dental Implant Surgery.

PURPOSE: New digital technologies enable real-time computer-aided (CA) three-dimensional (3D) guidance during dental implant surgery. The aim of this investigational clinical trial was to demonstrate the safety and effectiveness of a prototype optoelectronic CA-navigation device in comparison with the conventional approach for planning and effecting dental implant surgery. MATERIALS AND METHODS: Study participants with up to four missing teeth were recruited from the pool of patients referred to the University of Toronto Graduate Prosthodontics clinic. The first 10 participants were allocated to either a conventional or a prototype device study arm in a randomized trial. The next 10 participants received implants using the prototype device. All study participants were restored with fixed dental prostheses after 3 (mandible) or 6 (maxilla) months healing, and monitored over 12 months. The primary outcome was the incidence of any surgical, biologic, or prosthetic adverse events or device-related complications. Secondary outcomes were the incidence of positioning of implants not considered suitable for straightforward prosthetic restoration (yes/no); the perception of the ease of use of the prototype device by the two oral surgeons, recorded by use of a Likert-type questionnaire; and the clinical performance of the implant and superstructure after 1 year in function. Positioning of the implants was appraised on periapical radiographs and clinical photographs by four independent blinded examiners. Peri-implant bone loss was measured on periapical radiographs by a blinded examiner. RESULTS: No adverse events occurred related to placing any implants. Four device-related complications led to a switch from using the prototype device to the conventional method. All implants placed by use of the prototype device were in a position considered suitable for straightforward prosthetic restoration (n = 21). The qualitative evaluation by the surgeons was generally positive, although ergonomic challenges were identified. All study participants were present for the 1-year examination (n = 20 patients, 41 implants, 32 superstructures), and no complications or failures with any implants or superstructures were revealed. The peri-implant bone loss was less than 1 mm for all implants. CONCLUSION: Within the limitations of this trial, the prototype device provided placement of dental implants without adverse events.

Benchmarking Outcomes in Implant Prosthodontics: Partial Fixed Dental Prostheses and Crowns Supported by Implants with a Turned Surface over 10 to 28 Years at the University of Toronto.

PURPOSE: The aim of this noninterventional, retrospective study was to benchmark the outcomes of patients with partial fixed prostheses supported by implants treated at the University of Toronto at least 10 years earlier. A study protocol for assessing outcomes on like patients developed at the University of Bern, Switzerland, was followed. MATERIALS AND METHODS: All patients who had received at least one implant before 2002 were considered eligible to be included in the study (n = 298). The treatment histories were recorded from the patient chart of the participants, or from the participants' dentists by consent. Calibrated clinicians examined the study participants clinically and radiologically and recorded peri-implant mucosal status and observable technical and mechanical failures. Past adverse events were identified in the patient charts. Independent assessors measured bone levels on digitized radiographs. Statistical analysis included descriptive statistics at implants, teeth, and study participant levels, respectively. RESULTS: Of the 298 eligible patients, 121 attended a clinical examination (41%), while 12 declined (4%). The 121 study participants had received 321 implants between 1983 and 2001. The implants showed a success rate of 88.9% and a survival rate of 94% after an average of 17.5 years (SD 5.2, range 10 to 28 years). Approximately 5% of the surviving implants showed signs, or were associated with a prior history, of peri-implantitis. The distance from the implant shoulder to the first bone contact varied from -3 mm to 7 mm (mean = 1.52 mm [SD 1.57], median = 2.2 mm). Approximately half of the study participants had experienced at least one defect of their superstructure, representing a 52% "success rate," while the survival rate was 70%. The majority were very satisfied or satisfied with the treatment (102/121). CONCLUSION: A high proportion (94%) of conventional machined Brånemark System implants placed between 1983 and 2001 remained in function after an average of 17.5 years. The original superstructures predominantly fabricated as prefabricated acrylic teeth and acrylic resin reinforced with a cast palladium-silver alloy core were still in place for 70% of the participants, and 48% of the superstructures had never undergone any form of repairs.