Are there difficulty variables in maxillary third molar surgery? A prospective observational cohort study.

Background: The main aim of the present study was to assess which factors were related to surgical difficulty in maxillary third molar extraction. Intra- and postoperative complications were also evaluated.

Methods: A prospective observational cohort study was performed on out-patients who underwent impacted maxillary third molar extraction. Principal component analysis and multiple linear regression were used to assess the correlation among variables as well as the influence of different preoperative variables on surgical difficulty, suture duration and risk of intraoperative complications.

Results: Eighty-six teeth were extracted. There was a positive correlation between pre- and postoperative evaluations and surgery duration. Available space for surgical access in the upper fornix, second molar contact, crown palatal position, depth of the elevation point and surgeon's seniority had a significant effect on the overall difficulty index. Risk of intraoperative complications increased considerably as the percentage of reduction of maximum mouth opening increased (2.03±0.98) as well as in cases in which ostectomy and tooth sectioning were performed (7.02±2.68). The surgeon's seniority was associated with a decreased risk of intraoperative complications (-1.52±0.72). Surgeons were able to predict the difficulty of surgery only to a limited extent.

Conclusions: The percentage of maximum mouth opening reduction with an object in the fornix, crown palatal position, and contact with the second molar were found to be related to surgical difficulty.