Immediate Loading of Dental Implants Placed in Periodontally Infected and Non-Infected Sites: A 4-Year Follow-Up Clinical Study

Background: The aim of the present study is to compare the outcomes of immediate loading of implants in replacing teeth with and without chronic periodontal lesions at 4 years of follow-up. Methods: Thirty-seven patients were included in this study. A total of 275 implants were placed and immediately loaded in extraction sockets, 197 in periodontally infected sites (infected sites group [IG]), and 78 implants in non-infected sites (non-infected sites group [NG]). Marginal bone levels and clinical parameters (plaque accumulation and bleeding index) were evaluated at baseline and 12, 24, and 48 months after implant placement. Comparisons between IG and NG values over time were performed by the Student two-tailed t test. Results: At 48 months of follow-up, the IG presented a survival rate of 98.9% because two implants were lost 1 month after placement; the NG reported a survival rate of 100%. The marginal bone level was 0.79 +/- 0.38 mm for the IG and 0.78 +/- 0.38 mm for the NG, plaque accumulation was 0.72 +/- 0.41 for the IG and 0.71 +/- 0.38 for the NG, and the bleeding index was 0.78 +/- 0.23 for the IG and 0.75 +/- 0.39 for the NG. No statistically significant differences were reported between the IG and NG over time and between time points. Conclusion: At 48 months of follow-up, dental implants that were placed and immediately loaded in periodontally infected sockets showed no significant differences compared to implants placed in uninfected sites. J Periodontol 2010;81:1140-1146.