Department of Dental hygiene, Cheongam College1
Objectives: This retrospective study evaluated the changes in the airway width after the orthognathic surgery associated with the skeletal Class III malocclusion. Methods: The lateral cephalograms of 30 adult patients were taken before and immediately after the operation, and after the orthodontic treatment. The angles and distances of them were measured and compared. Results: Before the surgery, the mean value of mandibular (S-B) setback was 9.66 mm, and moved by 1.56 mm anteriorly after the orthodontic treatment. The ANB increased by 5.42 degrees, since then it decreased by 0.68 degree. The hyoid bone (S-APH) moved by 5.05 mm posteriorly, but then moved by 2.26 mm anteriorly. The soft tissue width of laryngeal pharynx (apw2-ppw2) was narrowed by 1.04 mm, and decreased by additional 0.83 mm after the orthodontic treatment. Conclusions: As the mandible was moved back, the location of hyoid bone and laryngeal pharynx were moved backward.
1. Hwang YI, Lee KH, Lee KJ, Kim SC, Cho HJ, Cheon SH, et al. Effect of airway and tongue in facial morphology of prepubertal Class Ⅰ,Ⅱ children. Korean J Orthod 2008;38(2):74-82. https://doi.org/10.4041/kjod.2008.38.2.74
2. Park SH, Yu HS. A comparison study of the effects of hypertrophied adenoid tissue on jaws morphology. Korean J Orthod 2002;32(1):19-31.
3. Lee MJ, Kim JG, Yang YM, Baik BJ. Effects of mouth breathing on facial skeletal morphology. J Korean Acad Pediatr Dent 2012;39(4):339-47. https://doi.org/10.5933/JKAPD.2012.39.4.339
4. Lee YS, Han SJ. Comparison of the change in the pharyngeal airway apace, tongue and hyoid bone positions according to the orthognathic surgical methods of mandibular prognathism. J Korean Assoc Maxillofac Plast Reconstr Surg 2013;35(4):211-20. https://doi.org/10.14402/jkamprs.2013.35.4.211
5. Choi YH, Kim BK, Choi BJ, Kim YG, Lee BS, Kwon YD, et al. An investigation of hyoid bone position and airway space in class 3 malocclusion after orthognathic surgery. J Korean Assoc Maxillofac Plast Reconstr Surg 2011;33(5):401-6.
6. Kim BS, Jung SG, Han MS, Jeoung YW, Kook MS, Park HJ, et al. Changes of pharyngeal airway space after mandibular setback surgery in computed tomography images. J Korean Assoc Maxillofac Plast Reconstr Surg 2011;33(1):36-43.
7. Chang HH, Kim JS, Yi CK. A study on the change of airway space and cranial, cervical angulation after mandibular setback operation. J Korean Assoc Oral Maxillofac Surg 2000;26(2):115-31. https://doi.org/10.1016/s0901-5027(97)81025-9
8. Kawakami M, Yamamoto K, Noshi T, Miyawaki S, Kirita T. Effect of surgical reduction of the tongue on dentofacial structure following mandibular setback. J Oral Maxillofac Surg 2004;62(10):1188-92. https://doi.org/10.1016/j.joms.2004.06.032
9. Lee JH, Paeng JY, Myoung H, Hwang SJ, Seo BM, Choi JY, et al. The three dimensional analysis of volumetric airway change in orthognathic surgery of mandibular prognathism. J Korean Assoc Maxillofac Plast Reconstr Surg 2005;27(6):552-8.
10. Faul F, Erdfelder E, Lang AG, Buchner A. G*Power 3: A flexible statistical power analysis program for the social, behavioral, and biomedical science. Behavior Research Methods 2007;39(2):175-91. https://doi.org/10.3758/bf03193146
11. Cohen J. Statistical power analysis for behavioral sciences. 2nd ed. Hillsdale: Elsevier; 1988:553-8.
12. Kang H. Sample size determination for repeated measures design using G Power software. Anesth Pain Med 2015;10(1):6-15. https://doi.org/10.17085/apm.2015.10.1.6
13. Broadbent BH. A new x-ray technique and its application to orthodontia. Angle Orthodontist 1931;1(2):45-66.
14. King EW. A roentgenographic study of pharyngeal growth. Angle Orthodontist 1952;22(1):23-37.
15. Lee SH. Study on airway size in class iii malocclusion by the gender. Korean J Phys Anthropol 2017;30(4):145-51. https://doi.org/10.11637/kjpa.2017.30.4.145