A simple score for evaluation of the complexity of third-molar extractions

Objectives: This article proposes a simple preoperative score to evaluate the complexity of tooth extractions of the third mandibular molar and to estimate the time involved. Study Design: We consider 11 factors (demographic, anatomic, and radiologic) that favor the surgery and that can be identified through standard clinical and radiologic examinations. The number of favorable factors (NFF) relative to each patient constitutes his/her score. The analysis of 1500 extractions performed by various surgeons with experience from 2 to 25 years evidences a quadratic inverse correlation between NFF and the time required for the surgery. Results: The shape of the time distribution suggests the existence of 3 major classes of patients characterized by time of 4 to 10 minutes, 11 to 20 minutes, and 21 to 40 minutes. The corresponding NFF brackets, as identified by their frequency distributions and validated by the receiver operating characteristic curve method, are 5 to 11 (mean [SD], 6.8 [1.6]), 2 to 4 (3.3 [1.3]), and 0 to 1 (0.8 [1.0]), respectively. Conclusions: Our results show the good performance of this score as a predictor of the surgical time and its applicability in daily practice regardless of operator experience, background, and level of surgical ability.