Does Mandibular Gonial Angle Predict Difficulty of Mandibular Third Molar Removal?

Abstract

Purpose: Predicting the difficulty of impacted mandibular third molar (IM3M) removal remains a controversial issue because many variables have been associated with increased operation time. Thus, the main objective of this study was to assess the influence of the gonial angle on the surgical difficulty of IM3M extraction.

Patients and methods: A prospective cohort study of patients requiring IM3M removal was conducted. The gonial angle measured with a goniometer was considered the primary predictor variable. The primary outcome variable was operation time. Difficulty also was recorded by surgeons using a 100-mm visual analog scale (VAS). Postoperative complications (pain, swelling, and trismus at 48 hours and 7 days) were registered as secondary outcome variables. A descriptive bivariate statistical analysis, Pearson correlations and scatter plots, and an explanatory multiple linear regression model were performed. Significance was set at P < .05.

Results: The sample comprised 60 participants (17 men and 43 women) with a mean age of 25.2 years (standard deviation, 7.1 years). No significant correlations were found between the gonial angle and operation time, VAS difficulty score, and postoperative complications. Regression analysis confirmed this lack of effect of the gonial angle. The operation time was significantly affected by surgical experience (P = .016) and patient age (P = .009), whereas the 100-mm VAS difficulty score was only related to surgical experience (P = .001).

Conclusions: The gonial angle is not related to the surgical difficulty of IM3M removal. Moreover, this variable is not associated with the occurrence of postoperative complications. According to the findings in this cohort, surgical experience and patient age are the only variables significantly related to increased operation time.