A 3-year follow-up study on single implant treatment.

The purpose of this study was to investigate restorative and postinsertion problems in patients provided with single implant supported restorations. Fifty consecutive single implant patients were reviewed over a period of 3 years following placement of artificial crowns. One (1.4%) of the 70 inserted implants was lost during the follow-up period, which gives a cumulative success rate of 98.5%. The most frequent complication was loosening of the single tooth abutment screw. This problem was associated with fistulas during the first year of clinical service. A more severe complication was that three adjacent teeth had to be endodontically treated due to accidental devitalization from surgical trauma during implant insertion. The mean marginal bone level adjacent to the implants was reduced 0.5 mm from crown insertion to the third annual review.