Evaluation Endosseous Dental Implants success Rate, Adverse Events, and Associated Risk Factors: A Retrospective Study.

Purpose: The purpose of this study was to understand the clinical performance of dental implants including surgical and prosthetic failure rates and potential correlations with patient- level and procedure-level factors.

Materials and methods: A retrospective cohort study was conducted with patients who received at least 1 dental implant at the Ohio State University College of Dentistry between January 1, 2016 and October 31, 2021, on adults age 18 years and older. The following measures were collected for analyses: procedure date, patient age, gender, race, body mass index (BMI), medical comorbidities, cardiovascular disease, autoimmune diseases, osteoporosis, cancer, oral conditions, periodontal condition, tobacco or alcohol use, parafunctional habits, tooth number and location, implant type and manufacturer, implant diameter and length, abutment type and manufacturer, definitive restoration type, provider demographics, type of post-procedure complication(s), and treatment notes.

Results: A total of 1,282 implants from 732 patients were recorded. Co-morbidities of interest in the patient population included 27% obesity, 10% diabetes mellitus, 9% cancer, and 28% hypertension. Two hundred and eight implants experienced some adverse event during the study period. Implant failures included failure to osseointegrate (2.9%) and loss of osseointegration (2.7%). Mechanical complications included abutment screw loosening (5.3%), abutment screw fractures (0.8%), and prosthesis fracture (1.0%). Soft tissue complications included peri-implantitis (2.6%) and peri-implant mucositis (7.2%). Among the 208 implants that experienced adverse events, forty-seven (3.6%) implants were removed. Ten (21.3%) of the failed implants were single crowns, and 3 (6.4%) were fixed dental prostheses or assisted a removable partial dental prosthesis. The remaining 34 implant (72%) failures occurred prior to prosthesis placement. The overall incident rate of implant adverse event was low, 7.5/100 person-years at a 95% confidence interval (CI); range: 6.4-8.5. Incident rates for implant failure, mechanical complications, and soft tissue complications were 1.6/100 (95% CI: range 1.2-2.1), 3.3/100 (95% CI: range 2.6-4.1), and 3.6/100 (95% CI: range 3.0-4.3).

Conclusions: Soft tissue complications such as peri-implantitis and peri-implant mucositis were the most commonly observed complications over time and appear to be associated with length of follow-up.