The necessity of pterygomaxillary disjunction in surgically assisted rapid maxillary expansion: A short-term, double-blind, historical controlled clinical trial.

PURPOSE: To evaluate and compare the short-term skeletal and dental changes following surgically assisted rapid maxillary expansion (SARME) with or without pterygomaxillary disjunction (PTMD) using cone beam computed tomography (CBCT).

MATERIAL AND METHODS: In present study, a total of 15 consecutive patients with transverse maxillary deficiency underwent SARME without PTMD. This prospective group was compared to one arm of a randomized controlled clinical trial the authors of present study published in 2014, in which 15 patients underwent SARME with PTMD. The age range of patients, inclusion and exclusion criteria, surgical procedure (except PTMD), operating surgeon, the appliance and protocol of expansion, and the method of outcomes evaluation were the same in both prospective (-PTMD) and historical control (+PTMD) groups. Before treatment and immediately after consolidation period, CBCT was obtained and the nasal floor width, interdental root distance, palatal bone width and interdental cusp distance were measured at first premolar and first molar regions of maxilla.

RESULTS: In both -PTMD and +PTMD groups, the greatest expansion occurred at the dental arch, followed by palatal bone and nasal floor level (V-shaped expansion in the coronal plane), and the amount of expansion achieved at the first premolar and molar areas was comparable (uniform widening of maxilla posteroanteriorly). There was no statistically significant difference in the amount and pattern of maxillary expansion between two groups.

CONCLUSION: Because of favorable surgical outcomes and decreased risk of possible perioperative complications, SARME without PTMD was recommended for the treatment of transverse maxillary deficiencies.