Long-term success of implants replacing a single molar.

Background: The aim of this study was to assess the long-term success and survival rates of implants replacing a single molar between two natural teeth and to evaluate the influence of implant characteristics on implant success.

Methods: The study was based on a consecutive cohort of 81 patients who received implants to replace a single molar between the years 1994 and 2004. Inclusion criteria for patients were having an implant replacing a molar between two natural teeth and follow-up data of at least 6 months. Data were recorded regarding the incidence of complications and success and survival rates of these implants.

Results: The range of follow-up was from 6 to 125 months (mean: 36 months). Smoking was reported by 18.5% of patients. The replacement of a mandibular molar was more frequent (87.7%), with 25.9% of the implants placed immediately after tooth extraction. Two implants were used to replace a single molar in seven patients (8.6%). The failure rate was 7.4% (six implants failed: three had broken necks, and three failed because of infection or bone loss). Complications included suppuration in 11.1% of implants and a pocket around the implant in two patients (2.5%). No relation was found among failure, complications, timing of implant placement, and smoking habits.

Conclusion: A single implant can serve as a good long-term and predictable treatment modality to replace a single molar with low complication and failure rates.