Failing factors associated with osseointegrated dental implant loss

Dental implants are currently the aesthetic and functional alternative for tooth replacement. Despite the high success rate shown by longitudinal studies, failures do occur, even in patients who present appropriate clinical conditions. The aim of the present study was to identify factors related to, or determinant of, dental implant loss in patients of the Latin-American Dental Research Institute, Curitiba, PR, Brazil. Retrospective analysis of 3578 records of patients who had implants placed in this institute during the period of 1996 to 2006 was performed. Beyond records, panoramic and periapical radiographs were analyzed. Of the 3578 individuals implant treated, failures occurred in 126 (3.5%) patients (mean age 52.2 +/- 10.6 years). Men lost more implants (4.5%) than did women (3.1%) (P = 0.05). Most failure occurred before loading (88.2%). Failure was more frequent when the implant was installed in the posterior jaw (58.5%). The main detectable causes of implant loss were evaluated. Most implant losses (75%) did not have an apparent clinical cause. Identified causes were 17.5% iatrogenic conditions (surgical technique, contamination, and/or occlusal trauma), poor bone quality and quantity (3%), peri-implantitis (1%), and 3.5% missing data. The results obtained in this study suggest that host factors can be contributing to the failure of implants.