Three dimensional evaluation of the effects of different treatment methods on pharyngeal respiratory airways in patients with skeletal class iii malocclusion

ABSTRACT Three Dimensional Evaluation of the Effects of Different Treatment Methods on Pharyngeal Respiratory Airways in Patients with Skeletal Class III Malocclusion Objective: The aim of this prospective study was to evaluate the effects of RME and/or face mask therapy on pharyngeal airways in patients with skeletal class III malocclusion by using cone-beam computed tomography three-dimensionally and to compare the results with an untreated skeletal Class III control group. Materials and Method: Sixty patients (34 males, 26 females; aged between 9-14 years) with skeletal class III malocclusion due to maxillary deficiency were included in this study. The patients were divided into four groups, each consists of 15 patients, as Group 1: RME, Group 2: RME+face mask, Group 3: face mask and Group 4: control group according to their treatment modalities. The effects of the applied treatment methods on the pharyngeal airways were assessed and compared with the control group using volumetric, areal and linear parameters via cone-beam computed tomography (CBCT) and Dolphin 3D (11.9 version) software. The obtained data were statistically assessed using the SPSS 20.0 program. Results: As a result of our study, there were statistically significant increases in all treatment groups in nasopharyngeal, retropalatal and total volume, whereas only for the RME group a statistically significant increase in the retroglossal volume was observed. The RME+face mask and the face mask groups showed statistically significant increases in the minimal axial area measurements. All treatment groups showed staticstically significant icreases in axial areas at the level of the PNS and only the face mask group showed a statistically significant increase at the level of the uvula, whereas the axial area measurements at the epiglottis level did not show any significant changes in any group. Conclusion: When all volumetric, areal and linear measurements were evaluated together, it had been found that pharyngeal respiratory airways had more significant positive changes in the nasopharyngeal and retropalatal regions, and these effects diminished towards the retroglossal region. In all treatment modalities, more significant increases were observed in the tranverse plane than observed in the sagittal plane. Keywords: Class III malocclusion, RME, face mask, respiratory airways, cone-beam computed tomography, Dolphin 3D software.