The predictors of implant failure after maxillary sinus floor augmentation and reconstruction: a retrospective study of 1045 consecutive implants.

Objective: To assess the predictors of implant failure after grafted maxillary sinus (GMS).

Material And Methods: A total of 1045 implants were inserted in 224 patients/347 GMS during a period of 14 years. Kaplan-Meyer and multivariate log-regression analysis were used to assess the following variates: patient's age, gender, smoker/nonsmoker, American Society of Anesthesiologists (ASA) class, one/two-stage surgery, merged/submerged healing, membrane, antibiotics, auto/allo/xenogenic bone grafts, implant's lengths/surface/diameter, crestal bone atrophy/quality, implant region, prosthetics, opposing dentition, and implant proximity to evaluate the predictors and relative risk (hazard ratio [HR]) of implant failure.

Results: Significant implant failure predictors were the graft material (HR = 4.7), with superior results for autogenic bone, residual crestal bone height (HR = 3.51), ASA class (HR = 2.73), surgical technique (HR = 2.56), implant proximity (HR = 2.07), smoker (HR = 1.98), and age (>60/HR=1.39). All other factors were insignificant. Overall survival rate was 93.3%.

Conclusions: GMS is effective when the predictors are considered. Patient selection, including the ASA status, smoking, residual bone height, and the graft material are the predominant predictors. In highly atrophic situations, autogenic bone grafts showed superiority; however, in less atrophic cases, nonautogenic bone-grafts are equivalent.