Risk factors for inflammatory complications following third molar surgery in adults

To estimate the frequency of inflammatory complications (surgical site infection and alveolar osteitis) following third molar (M3) extraction and identify risk factors for such complications.

This study was designed as a prospective cohort study and enrolled a sample composed of subjects having >or=1 M3 extracted as part of the American Association of Oral and Maxillofacial Surgeons' Age-Related Third Molar Study. Predictor variables were categorized as demographic, health status, anatomic, and pathologic factors. The outcome variable was the presence of a postoperative inflammatory complication (ie, surgical site infection or alveolar osteitis). Descriptive and bivariate statistics were computed. Variables with P values less than .15 in bivariate analyses were included in a multiple logistic regression model, used to identify factors associated with inflammatory complications.

The study sample consisted of 4,004 subjects with a mean age of 39.8 +/- 13.6 years having 8,748 M3s extracted. In bivariate analyses, impaction level, periodontal disease in or around M3, pre-existing infection around M3, and M3 pathology were associated with postoperative inflammatory complications. In the multiple regression model, level of impaction (soft tissue: odds ratio [OR] = 2.5; 95% confidence interval [CI], 1.7, 3.7), partial bony OR = 4.7 (95% CI, 3.6, 6.1), full bony, 6.0 (95% CI, 4.7, 7.7); P < .0001), and pre-existing infection (OR = 1.3 [95% CI, 1.0, 1.6; P = .05) or pathology (OR = 3.1; 95% CI, 2.2, 4.3; P < .0001) were associated with an increased risk of inflammatory complications following M3 surgery.

Level of impaction, pre-existing infection, and pathology were associated with increased risk for postoperative inflammatory complications following M3 surgery.