Clinical audit of posterior three-unit fixed-movable resin-bonded fixed partial dentures – A retrospective, preliminary clinical investigation

Abstract Background Two-unit cantilevered resin-bonded fixed partial dentures (RBFPDs) have higher retention rates over longer span fixed–fixed RBFPDs. It has been hypothesized that interabutment stresses associated with fixed–fixed designs cause prosthesis debonds therefore for the replacement of molar-sized and longer spans, non-rigid connectors have been used to allow independent movement between two abutment teeth. Objectives This preliminary study evaluates the clinical longevity and subjects’ satisfaction of three-unit fixed-movable (FM3) RBFPDs provided at a dental teaching hospital. Materials and methods Subjects who had received FM3 RBFPD(s) in the posterior region were clinically reviewed for complications. History of any debonds and subjects’ satisfaction to the prosthesis was recorded. Time-to-debond (retention rate) and time-to-loss (survival rate) of these prostheses were presented in life tables. Results Ninety-eight prostheses in 84 subjects were examined. Their mean service life was 31.8 months (SD 11.5, range 3–67 months). Twenty-two prostheses had a history of debond, resulting in a retention proportion of 77.6%; seventeen of these were rebonded and still present at the time of review. One prosthesis was lost after extraction of a periodontally-involved abutment tooth, giving a survival proportion of 93.9%. High subject satisfaction and no adverse outcome were reported. Conclusion Three-unit fixed-movable RBFPDs have a shorter success than two-unit cantilevered RBFPDs. However, non-rigid connectors allow the possibility of rebonding giving satisfactory short-term survival rate. Further research is needed to investigate their long-term efficacy. Clinical significance Three-unit fixed-movable RBFPDs incorporating non-rigid connectors may be a feasible option for replacement of molar-size pontic in the posterior region.