Review Article Rapid Maxillary Expansion and Upper Airway Morphology: A Systematic Review on the Role of Cone Beam Computed Tomography Gabriele Di Carlo, 1 Matteo Saccucci, 1 Gaetano Ierardo, 1 Valeria Luzzi, 1 Francesca Occasi, 2 Anna Maria Zicari, 2 Marzia Duse, 2 and Antonella Polimeni 1 1 Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, Rome, Italy 2 Department of Pediatrics, Sapienza University of Rome, Rome, Italy Correspondence should be addressed to Matteo Saccucci; matteo.saccucci@uniroma1.it Received 28 March 2017; Revised 22 May 2017; Accepted 8 June 2017; Published 16 July 2017 Academic Editor: Eiichi Honda Copyright © 2017 Gabriele Di Carlo et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objective. Tis study aimed to investigate the quality of cone beam computed tomography (CBCT) studies evaluating the efects of rapid maxillary expansion on upper airway morphology. Materials and Methods. A database search was conducted using PubMed, Ovid, and Cochrane Library up to December 2016. Studies in which CBCT was adopted to visualize the upper airway before and afer rapid maxillary expansion were included. Te population target was growing patients. Methodological quality assessment was performed. Results. Te screening process resulted in the exclusion of 1079 references, resulting in only 9 remaining papers that fulflled the inclusion criteria. No randomized clinical trials were found. Te quality scores ranged from 36% to 68% of the maximum achievable, and the mean quality score of the studies was 50%. No good quality studies were detected in our sample. Conclusions. Inconsistencies in the CBCT protocols utilized were detected between studies. Head posture, tongue position, and segmentation protocols were not consistent. Tese discrepancies were refected in the diferent results obtained in the studies. A valid and consistent protocol with regard to head and tongue positioning, as well as nasal cavity volume segmentation, is required. 1. Introduction In the feld of orthodontics, the classical studies performed on airway and craniofacial morphology using plane radiog- raphy in the 1970s have received renewed interest afer the introduction of cone beam computed tomography (CBCT) [1, 2]. Although magnetic resonance (MR) and computed tomography (CT) were available before its introduction, CBCT is now the most commonly used technology to acquire digital data on the anatomy of the nose and pharynx in dentistry. Te reduced costs and radiation dose for the patient compared to magnetic resonance imaging (MRI) and CT have contributed to the increased use of this technology [3, 4]. In the feld of orthodontics, CBCT has added value when upper airway defnitions are required for diagnosis and treatment planning [5]. Moreover, the use of sofware reconstruction in three dimensions enabled the manipulation of images in a three-plane space [6, 7]. Tese features enhance studies aiming to assess upper airway volume and morphology with respect to craniofacial growth, as well as maxillofacial surgical and orthodontic interventions [3, 4]. In this context, the dentoskeletal efects of rapid maxillary expansion (RME) have been extensively studied using dif- ferent methodologies, from manual measurement of dental casts to plane lateral cephalometrics [5, 6]. Nevertheless, the drawbacks that characterize plane radiography, in particular the superimposition aspects, hinder eforts to depict the three-dimensional efects of RME treatments with respect to the nasopharyngeal cavity. Te interest in maxillary expansion is mainly clinical. Maxillary constriction can play a role in the development of obstructive sleep apnea (OSA), and in childhood, it may ofen be related to the existence of allergic rhinitis [7–16]. Recently, RME has been advocated as a treatment modality Hindawi BioMed Research International Volume 2017, Article ID 5460429, 10 pages https://doi.org/10.1155/2017/5460429