Single-Tooth Implants and Their Role in Preserving Remaining Teeth: A 10-Year Survival Study

The use of teeth as abutments for fixed and removable partial dentures can result in biologically destructive consequences. Teeth adjacent to edentulous spaces should exhibit improved prognoses if restorative trauma is to be avoided or minimized. Implants offer a method of tooth replacement without relying upon the surrounding dentition for support. This investigation evaluates implant survival and prosthetic complications of implants that replaced single missing teeth and were placed in clinical practice during a 10-year period. It further examines preoperative status and survival of teeth adjacent to these implant restorations during the same 10-year time span. Ninety-nine patients treated with 116 implants and 112 single-tooth implant prostheses in a prosthodontic practice were examined between 1988 and 1998. The purpose of this study was to evaluate the role of implants in preventing the use of intact teeth for initial support of prostheses and in avoiding the use of additional teeth as abutments upon the replacement of existing restorations. Three implants failed over a 10-year period, for a survival rate of 97.4%. Complications included the loss of 2 implant crowns, screw loosening, broken screws, cement washout, margin exposure, and porcelain fracture. Of 196 teeth adjacent to edentulous spaces, 156 (79.6%) were intact or minimally restored. Only 3 of these teeth were restored as part of initial prosthodontic therapy. Over the ensuing 10 years, only 1 tooth required a replacement restoration, and 1 tooth was extracted. Results of this patient evaluation demonstrated that implant survival over a 10-year period was favorable, with minimal prosthetic complications. Furthermore, teeth adjacent to single-tooth implants exhibited an extremely low complication rate. This report indicates that implants can be effective in preserving intact teeth in patients undergoing initial prosthodontic therapy and in preventing the use of additional teeth as abutments in patients whose existing prostheses must be replaced. Schlagwörter: abutment, biologic risks, dental implants, fixed partial denture, single-tooth implant, survival, tooth loss, tooth preservation