Long-term marginal preiimplant bone loss in edentulous patients

Purpose: The aim of this study was to examine the long-term periimplant bon e loss in patients treated with implant-supported fixed prostheses in both jaws. Materials and Methods: The participants comprised 44 edentulous patie nts who have been followed for a 15-year period after treatment with a fixe d implant-supported prosthesis in the mandible. Thirteen of them also recei ved an implant-supported fixed prosthesis in the maxilla, on average 4.5 ye ars after the mandibular treatment. The periimplant bone level was measured on intraoral radiographs. Results: The long-term results of the implant tr eatment were successful, and only 1% (3/273) of the implants were lost in t he mandible and 7% (5/75) in the maxilla. All but one of the failures occur red before the connection of the prostheses. The mean marginal bone loss ar ound the implants was small (less than 1 mm for a 10-year period after impl ant placement), and was of similar magnitude in both jaws. However, the ind ividual variation was relatively great. There was no significant difference in marginal bone loss between those who had a maxillary complete denture d uring the entire observation period and those who had received a fixed impl ant-supported maxillary prosthesis. Smokers lost more periimplant bone than did the nonsmokers; the difference was significant in the mandible but sma ll and nonsignificant in the maxilla. Conclusion: The long-term periimplant bone loss was small and of similar magnitude in the mandible and the maxil la in subjects who had received implant-supported fixed prostheses in both jaws. The prosthetic status in the maxilla, ie, complete denture or fixed i mplant-supported prosthesis, had no significant influence on the mandibular periimplant bone loss.