ORIGINAL ARTICLE   

European Journal of Oral and Maxillofacial Surgery 2020 August;4(2):35-44

DOI: 10.23736/S2532-3466.19.00186-3

Copyright © 2019 EDIZIONI MINERVA MEDICA

language: English

Changes in pharyngeal airway volume after mandibular advancement and maxillomandibular advancement: a cone beam computed tomography study

Thenmozhi THIRUMAVALAVAN ✉, Selva KUMAR, Shanmugasundaram SOMASUNDARAM, Guru PRASAD, Krishna K. RAJA

Department of Oral and Maxillofacial Surgery, SRM Dental College, Ramapuram, Chennai, India

BACKGROUND: The study evaluates the volume of pharyngeal airway space, head posture, hyoid bone position and tongue position three dimensionally using CBCT scan after mandibular advancement.
METHODS: The study was conducted in 14 individuals who underwent BSSO Advancement with or without maxillary impaction. The scan was taken in natural head position preoperatively and follow-up of one year. The pharyngeal airway volume was measured using 3D MATIC software. The hyoid bone position and head posture was measured in sagittal sections. The hyoid bone was measured in horizontal and vertical axis with relation to cranial base. The head posture was measured using craniocervical angle. The results were statistically analysed using paired t test and Wilcoxon signed rank test.
RESULTS: The study concludes with increase in volume of oropharyngeal and hypopharyngeal airway three dimensionally after BSSO advancement. The head posture angulation decreased after surgery, and hyoid bone moved forward and upward postoperatively. The tongue position measurements increased in relation to (Posterior Nasal Spine) PNS indicating increase in size of tongue anteroposteriorly and show forward movement of tongue in relation to Basion (Ba).
CONCLUSIONS: The amount of airway was calculated, associated in changes with hyoid bone position, tongue position and head posture were measured after mandibular advancement. Thus, these procedures show direct or indirect postoperative impact of soft and hard tissues.

KEY WORDS: Pharynx; Hyoid bone; Head; Posture