Risk factors for complications from challenging lower third molar extractions in tertiary hospital patients

Abstract

Objective: Third molar extraction is a common procedure with occasional complications. This study aimed to determine the incidence and types of complications in challenging lower third molar extractions and to identify complication risk factors in tertiary hospital patients. Material and methods: A retrospective cohort study was conducted on 354 patients who underwent unilateral lower third molar extraction during a 2-year period in 2018–2019 at Helsinki University Hospital. The outcome was the presence of a complication, and patient-related and operation-related variables served as determinants. Statistical analyses included Mann–Whitney U and Chi-squared tests, and binary logistic regression. Results: Complications occurred in 16.7% of patients. The most common complication was local infection (7.6%), followed by nerve injury (5.6%). The complication risk was 3.7-fold (95% confidence interval (CI) 1.97–6.77, p < 0.001) higher in extractions defined as demanding than in routine operative extraction. If the third molar was acutely infected, the complication risk increased 2.0-fold (95% CI 1.08–3.75, p = 0.027). Conclusions: Due to the high rate of complications in challenging extractions, scheduling a follow-up visit is important, and risk factors must be considered properly, especially in demanding extractions and in acutely infected third molars.