Effect of osteotomy of the pterygoid process on maxillary disjunction: a double-blind, randomized controlled trial

Surgical maxillary expansion is indicated for the treatment of transverse facial deformities of the upper arch. The aim of this study was to evaluate the effect of osteotomy of pterygoid processes on the posterior gain of atrophic maxilla of individuals with bilateral transverse deficiency, from adouble-blind parallel-arm randomized controlled trial, of a convenience sample. Distances between the two medial and lateralpterygoid plates, and the inclinations of the lateral pterygoid plates, were analyzed using computed tomography in the preoperative period and at 30 days post-expander device (maximum maxillary expansion). The increases in the distance between the two medial pterygoid plates linear measurements were significantly greater in Group 2 than in Group 1, as well as those of distance between the two lateral pterygoid plates. The posterior gain in both groups confirmed the efficiency of maxillary expansion surgery without or with osteotomy of the pterygoid processes. The mean posterior amplitude was approximately twice that observed in Group 2, compared to Group 1. The osteotomy of the pterygoid process resulted in greater posterior gain in maxillary expansion surgeries.