Risk Factors of Early Implant Failure: A Retrospective Study

Abstract

Objective The aim of this retrospective study was to assess the potential risk factors that lead to early implant failure.

Materials and methods The medical records of patients who received implant (Bränemark System, Nobel Biocare, Gothenburg, Sweden) surgery within the period 2008–2014 at the Department of Dentistry, Asan Medical Center, were carefully reviewed. Data collection and analysis mainly focused on systemic, anatomic, implant, and operative factors. The outcome variable was early implant failure.

Results In 321 patients, including 150 women and 171 men, whose mean age was 54.4 years (range, 18-81 years), 1014 implants were installed. Thirty-four implants in 29 patients failed to osseointegrate, corresponding to an early implant failure rate of 3.4%. The early implant failures were significantly associated with smoking habit (p < 0.05), implant site (p < 0.05), bone quality (p < 0.05), timing of implant surgery (p < 0.01), and horizontal ridge augmentation (p < 0.05). Multivariate logistic regression analysis established the significance of smoking habit (Odds ratio (OR) = 2.7, p < 0.05), bone quality (OR = 2.0, p < 0.05), timing of implant surgery (OR = 3.9, p < 0.01), and horizontal ridge augmentation (OR = 2.3, p < 0.05).

Conclusions The risk factors of early implant failure were smoking habit, bone quality, timing of implant surgery, and horizontal ridge augmentation. Therefore, such systemic and local factors should be considered in planning implant installation in order to prevent early implant failure.