Implant-supported Laserwelded Titanium Frameworks in Edentulous Mandibles: 15-Years Follow-up

Objectives: Long-term knowledge of different framework materials in the edentulous implant patient is not available for 15-years follow-up. The aim was to report and compare 15-year data on implant-supported prostheses in edentulous mandibles provided with laser-welded titanium and gold-alloy frameworks. Methods: Consecutively were 155 patients treated with abutment level prostheses with two early generations of fixed laser-welded titanium frameworks (test groups 1 and 2). Fifty three randomly selected patients with gold-alloy castings formed the control group. Clinical and radiographic 15-year data was collected and compared for the groups. Results: All patients followed-up for 15 years (n=72) had still a fixed prosthesis in the mandible (Cumulative Survival Rate, CSR 100%). The 15-years original prosthesis CSR was 89.2% and 100% for titanium- and gold-alloy frameworks, respectively (p=0.0573). The overall 15-years implant CSR was 98.7% (loaded implants; 99.3%) furthermore 99.1% and 99.6% for loaded implants in the test and control group, respectively. Average 15-year bone loss was 0.59 (SD 0.56) mm for the titanium group and 0.98 (SD 0.64) mm for the control group (p=0.0313). Few (1.8%) of the implants had > 3.1mm accumulated bone loss after 15 years in function. The most common complications for titanium frameworks were resin veneer fractures, soft tissue inflammation, and fractures of the metal frame in total 15.5% of the patients. Loose and fractured implant screw components were few (2.4%). Conclusion: Predictable overall long-term results could be achieved with the present treatment modality. Fractures of the metal frames and remade prostheses were common for the laser-welded titanium frameworks, and the titanium frameworks had a tendency to work poorly when compared to gold-alloy frameworks during 15 years. An average more bone loss was observed for implants supporting gold-alloy frameworks during 15 years in function (p=0.0313).