Evaluations of Endosseous Dental Implant Success Rates, Adverse Events, and Associated Risk Factors: A Retrospective...

To understand the clinical performance of dental implants via surgical and prosthetic failure rates and potential correlations with patient-level and procedure-level factors.

A retrospective cohort study was conducted with patients aged 18 years or older who received at least one dental implant at The Ohio State University College of Dentistry between January 1, 2016, and October 31, 2021. The following measurements were collected for analyses: procedure date, patient age, sex, race, body mass index, 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 postprocedure complication(s), and treatment notes.

A total of 1,282 implants from 732 patients were analyzed. Comorbidities of interest in the patient population included obesity (27%), diabetes mellitus (10%), cancer (9%), and hypertension (28%). In addition, 208 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, 47 (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 failures (72%) occurred prior to prosthesis placement. The overall incidence rate of implant adverse events was low (7.5 ⁄ 100; 95% confidence interval [CI]: 6.4 to 8.5). The incident rates for implant failure, mechanical complications, and soft tissue complications were 1.6 ⁄ 100 (95% CI: 1.2 to 2.1), 3.3 ⁄ 100 patient-years (95% CI: 2.6 to 4.1), and 3.6 ⁄ 100 patient-years (95% CI: 3.0 to 4.3), respectively.

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