Early Implant Failure Associated With Patient Factors, Surgical Manipulations, and Systemic Conditions

Purpose: Systematic monitoring of important clinical outcomes is increasingly important for health-care decision making, especially in the context of continuous quality improvement. Dental implant failure within the first year (early failure) has been previously shown to be more common than subsequent failure. The purpose of this study was to identify associations between early implant failure and patient factors, surgical manipulations, and systemic conditions.

Materials and methods: The authors retrospectively identified the records of consecutive adult patients with dental implants seen between 2000 and 2014 in the Department of Dental Specialties, at the Mayo Clinic. Demographic, surgical, and medical data were extracted from the database and individual medical records to determine time to first implant failure. Cox proportional hazards regression models were used to assess associations of demographic, surgical, and systemic conditions with implant failure during the first year post-implantation, summarized as hazard ratio (HR) (95% confidence interval [CI]).

Results: Among 8540 implants identified during the study period, 362 (4.2%) failed within the first year of placement at a mean (SD) of 129 (96) days after placement. On univariate analysis, most candidate predictors were not shown to influence first-year failure. Preplacement surgical manipulations associated with increased early implant failure were bone augmentation only (HR, 1.45; 95% CI, 1.02-2.05; p = 0.04), socket preservation (HR, 2.67; 95% CI, 1.33-5.38; p = 0.006), and xenogenic material (HR, 2.12; 95% CI, 1.11-4.04; p = 0.02). Alveoloplasty only at placement was associated with decreased early implant failure (HR, 0.33; 95% CI, 0.17-0.65; p = 0.001). Overall, 318 implants (3.7%) had surgical complications within the first year of placement at a mean (SD) of 110 (114) days after placement; any surgical complication was significantly associated with early implant failure (hazard ratio, 15.84; 95% CI, 11.10-22.61; p < 0.001). After adjustment for age, sex, and implant era, no single or multiple medical condition(s) and no single or multiple medication(s) increased patient risk of implant failure in the first year after placement.

Conclusions: These findings support a targeted effort to reduce the incidence of surgical complications to reduce early failure of dental implants.