Effect of Surgically Assisted Rapid Maxillary Expansion on Upper Airway Volume: A Systematic Review

Purpose: Surgically assisted rapid maxillary expansion (SARME) is required in non-growing patients when maturity or resistance precludes desired sutural separation by noninvasive techniques. The aim of this review was to determine what volumetric changes occur in the upper airway spaces after SARME in adults. Materials and Methods: A systematic review was performed with data assessed for suitability of meta-analysis. The primary outcome measurement of volumetric changes in an upper airway space was sought in non-growing patients undergoing SARME. Electronic database searches were performed for published literature in Medline (by Ovid), Pre-Medline, Old Medline, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) spanning all available years to August 1, 2015. Unpublished literature was searched electronically through ClinicalTrials.gov and the National Research Register. Additional hand searching of reference lists of relevant articles, grey searching, and expert correspondence was conducted for any additional studies. Two authors independently screened search results, extracted data, and assessed the risk of bias of included studies. Results: Twenty-one studies were located by initial screening; 10 were excluded after full-text review, leaving 11 studies eligible that met all inclusion criteria for this systematic review. In total, 204 treated patients (mean age, 18 to 31 yr) were included in the qualitative synthesis. Ten studies evaluated nasal cavity volume, 2 evaluated palatal volume, and 1 evaluated oropharyngeal volume. Appliances used included tooth-borne hyrax and transpalatal distractor devices. Conclusions: SARME was found to produce substantial short-term volume increases in the nasal cavity in non-growing patients that were maintained for at least 63 months. Evidence weakly suggested no effect on oropharyngeal volume. However, most studies were evaluated as having a high risk of bias. The effect of such volume changes on respiratory function still needs to be determined; thus, SARME cannot be recommended for respiratory purposes. Crown Copyright (C) 2016 Published by Elsevier Inc on behalf of the American Association of Oral and Maxillofacial Surgeons. All rights reserved