Early bone loss is a predictor for peri-implantitis development: Results from a 10-year prospective cohort study

MCGBJ ORAL COMMUNICATION CLINICAL RESEARCH – PERI-IMPLANT BIOLOGY

Background: It is widely perceived that following implant placement and abutment connection, a limited bone loss (defined in literature as marginal bone loss or initial bone loss or initial bone remodelling) may occur. This is basically biologically driven as a result of establishment of a biologic seal between soft tissues and implant and/or restorative components. On the other hand, this initial crestal bone remodelling may also lead to unwanted implant surface exposure to soft tissues.

Aim/Hypothesis: To evaluate if early bone loss, including initial bone loss (IBL), is predictive for future development of peri-implantitis and implant loss.

Materials and Methods: All patients were initially referred by their general dentist and treated between 2005 and 2009 with the same implant system (OsseoSpeed, Dentsply Sirona Implants). The single inclusion criterion was a follow-up time of at least 10 years. Implant survival, health and bone loss were evaluated during recall visits. Radiographs taken at recall visits were compared with the post-surgical ones (baseline). Simple NO-parametric testing was performed in cross-tabs using Pearson Chi-square test and Fishers's exact test. Kaplan-Meier estimated survival curves were plotted for different thresholds for IBL (0.5 mm and 1 mm) at different times (1- and 2-years post-op). Simple generalized linear mixed models with binomial distribution and logit link for peri-implantitis were fitted. An adjusted logistic mixed model was made for peri-implantitis, with adjustment for smoking status, history of periodontitis and IBL at 1 year >0.5 mm.

Results: 407 patients (221 women, 186 men; mean age of 64.86 years (range 28–92, SD 10.11)), with 1482 implants, responded. Average follow-up time was 10.66 years (range 10–14, SD 0.87). Absolute implant survival rate was 94.74%. MBL of 0.81 mm (SD 1.58, range 0.00–17.00) was seen after a follow-up of 10 years. 175 implants (76 patients) were diagnosed with peri-implantitis (11.81% on implant level, 18.67% on patient level). Differences between groups for each threshold were statistical significant for both peri-implantitis and implant loss. Implants with >0.5 mm IBL during the 1st year of function show 5.43 times higher risk in developing peri-implantitis. Probability in developing peri-implantitis was 52.06% when smoking, susceptibility for periodontitis and IBL of >0.5 mm was combined.

Conclusions and Clinical Implications: The present study suggests that early bone loss is a predictor for development of long-term peri-implant pathology, with a significant higher risk for peri-implantitis when early bone loss exceeds certain proposed thresholds.

Keywords: Implant, peri-implantitis, predictor, early bone loss, long term.