Abstract
PURPOSE: Early postoperative infection can lead to dental implant failure. This study aimed to evaluate the frequency of failed and survived implants after acute postoperative infection and the related factors. MATERIALS AND METHODS: This cross-sectional cohort evaluated early infection after dental implant surgery. The study variables included the site of implant placement, age and gender of patients, bone augmentation, postoperative antibiotic therapy, smoking, and time of infection occurrence or diagnosis. Failed and survived implants were the outcome of the study. The patients were studied in 2 groups of survived implants (group 1) and failed implants (group 2). RESULTS: Thirty-four (3.46%) out of 980 patients developed a postoperative infection following implant placement, which included 25 males and 9 females. Ten implants (29.4%) survived (group 1), and 24 implants (70.6%) failed (group 2). There were significant differences between the 2 groups regarding the number of smoker patients, fresh socket or delayed implant placement, patients who received bone graft, and the meantime of diagnosis (P < 0.05). Regarding the covariates, the Kaplan-Meier analysis showed that the risk of implant failure in patients who did not receive postoperative antibiotic therapy increased by 1.1 times (hazard ratio) when infection occurred four days after surgery. In patients who received postoperative antibiotics, the risk of failure increased when infection occurred after 6 days in smokers and after 9 days in non-smokers. CONCLUSION: Considering the study results, it seems that smoking, early infection, fresh socket placement, and placement of implants along with bone substitutes may increase the failure rate after acute infection in dental implant placement.