Sequential changes in pharyngeal airway dimensions after mandibular setback surgery and its correlation with postsurgical stability in patients with mandibular prognathism

Aim: To cephalometrically evaluate the alterations taking place in the pharyngeal airway space, hyoid bone, soft palate, and head posture after mandibular setback surgery (bilateral sagittal split osteotomy) for correction of mandibular prognathism, as well as to evaluate the immediate postsurgical and more than 6 months postsurgical adaptations of these structures. Setting and Design: A retrospective cephalometric study. Materials and Method: The study group consisted of 40 nongrowing patients (20 females and 20 males) with mandibular prognathism and ANB less than or equal to –2 degree for which mandibular setback surgery by bilateral sagittal split ramus osteotomy was performed along with fixed appliance therapy. There presurgical (T1), immediate postsurgical (T2), and more than 6 months postsurgical (T3) lateral cephalograms were analyzed. Statistical Analysis Used: Intragroup comparison was done by paired t-test. Results: Skeletal measurements after orthognathic surgery remained stable in the long term. It was evident that mandibular setback surgery narrowed the pharyngeal airway; however, these changes were not significant except at the base of the tongue. During the follow-up airway measurements at the base of the tongue, the intersection of tongue at the inferior border of mandible and the vallecula increased but they did not reach the presurgical values. Soft palate length increased significantly after surgery. Angulation of soft palate to nasal line also increased significantly following surgery but decreased during follow-up. Extension of the head occurred after surgery which was maintained even at long term. Conclusion: Careful analysis of airway should be performed, particularly in connection with large anteroposterior discrepancies and in those who have risk factors for development of obstructive sleep apnea. Such cases should be corrected by combined maxillary and mandibular osteotomies.

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Computational fluid dynamics study of the pharyngeal airway space before and after mandibular setback surgery in patients with mandibular prognathism

International Journal of Oral and Maxillofacial Surgery ◽

10.1016/j.ijom.2017.03.028 ◽

2017 ◽

Vol 46 (7) ◽

pp. 839-844 ◽

Cited By ~ 6

Author(s):

Y. Yajima ◽

M. Oshima ◽

T. Iwai ◽

H. Kitajima ◽

S. Omura ◽

...

Keyword(s):

Fluid Dynamics ◽

Computational Fluid Dynamics ◽

Mandibular Prognathism ◽

Pharyngeal Airway ◽

Mandibular Setback ◽

Before And After ◽

Mandibular Setback Surgery

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Comparison of Pharyngeal Airway between Mandibular Setback Surgery Patients (Skeletal Class III) and Nonsurgery Patients (Skeletal Classes I and II)

BioMed Research International ◽

10.1155/2019/5012037 ◽

2019 ◽

Vol 2019 ◽

pp. 1-6

Author(s):

Jung-Hsuan Cheng ◽

Chun-Ming Chen ◽

Ping-Ho Chen ◽

Szu-Ting Chou ◽

Chin-Yun Pan ◽

...

Keyword(s):

Hyoid Bone ◽

Class Ii ◽

Class I ◽

Class Iii ◽

Pharyngeal Wall ◽

Skeletal Class ◽

Pharyngeal Airway ◽

Mandibular Setback ◽

Mandibular Setback Surgery ◽

Airway Dimensions

Purpose. We investigated the pharyngeal airway dimensions and their correlations in patients who underwent mandibular setback surgery versus those who did not. Materials and Methods. One hundred and sixty cephalometric radiographs (120 patients) were obtained from patients with three skeletal malocclusion classifications: Class I and Class II in the nonsurgery group and Class III in the surgery group (preoperative and postoperative cephalograms). The following dimensions were measured: nasopharyngeal airway (NOP), uvulopharyngeal airway (UOP), shortest distance from the posterior tongue to the pharyngeal wall (TOP), and distance from the epiglottis to the pharyngeal wall (EOP). Paired t test, one-way analysis of variance, and Pearson correlation coefficients were used for statistical analysis. Results. Preoperatively, UOP and TOP of skeletal Class III patients (15.2 mm and 16.6 mm) were significantly larger than those of skeletal Class II (11.5 mm and 12 mm) and Class II (12.3 mm and 12.9 mm) patients, respectively. No differences were observed in EOP between the three skeletal patterns. The hyoid bone of Class III patients was significantly anterior to that of Class I/II patients. Furthermore, UOP had a moderate negative correlation with soft palate length. Postoperatively, no significant difference (UOP, TOP, EOP, soft palate width, and hyoid bone) was found between the skeletal classes. Conclusion. Preoperatively, UOP and TOP of skeletal Class III patients were significantly wider than those of skeletal Class I/II patients. Pre- and postoperatively, EOP did not exhibit significant differences among the three skeletal classifications. No differences were found in all postoperative pharyngeal airway dimensions between Class III patients and nonsurgery patients (Class I and Class II).

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Multislice computed tomography assessment of airway patency changes in the supine position following mandibular setback surgery for mandibular prognathism: A prospective 1-year follow-up study

APOS Trends in Orthodontics ◽

10.25259/apos_169_2020 ◽

2021 ◽

Vol 11 ◽

pp. 106-115

Author(s):

Koji Iwai ◽

Hiroshi Ueda ◽

Toshikazu Nagasaki ◽

Cynthia Concepcion Medina ◽

Yu Matsumura ◽

...

Keyword(s):

Computed Tomography ◽

Multislice Computed Tomography ◽

University Hospital ◽

Airway Patency ◽

Mandibular Prognathism ◽

Pharyngeal Airway ◽

Mandibular Setback ◽

Post Surgery ◽

Mandibular Setback Surgery

Objectives: The purpose of this study was to perform a three-dimensional analysis on the pharyngeal airway of supine patients who have undergone mandibular setback surgery, using multislice computed tomography (MSCT). We also measured the respiratory disturbance index pre- and post-surgery, using a portable sleep monitor. Materials and Methods: The subjects included two males and nine females who were diagnosed with mandibular prognathism at Hiroshima University Hospital and were scheduled to undergo the bilateral sagittal split osteotomy. Using a CT scanner, baseline MSCT images were obtained from the subjects before surgery for morphological analysis, and then the two further scans were obtained after mandibular setback surgery. All patients were provided with at-hoeme sleep monitor to use it both at baseline and approximately 1 year after surgery. Results: Middle and epiglottis pharyngeal space and cross-sectional area were significantly decreased immediately after setback surgery, but did not change further over the 1-year period. Mandibular setback was not associated with the development of sleep breathing disorder (SBD) during the 1-year follow-up period. Conclusion: We found no evidence that the reduction in the pharyngeal airway space immediately after mandibular setback surgery recovered significantly during the follow-up period, although mandibular setback was not associated with development of SBD.

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Correlation between the Pharyngeal Airway Space and Head Posture after Surgery for Mandibular Prognathism

BioMed Research International ◽

10.1155/2015/251021 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Chun-Ming Chen ◽

Steven Lai ◽

Ker-Kong Chen ◽

Huey-Er Lee

Keyword(s):

Mandibular Prognathism ◽

Head Posture ◽

Oropharyngeal Airway ◽

Pharyngeal Airway ◽

Mandibular Setback ◽

Postoperative Changes ◽

Lateral Cephalograms ◽

Intraoral Vertical Ramus Osteotomy ◽

Mandibular Setback Surgery ◽

Vertical Ramus Osteotomy

Purpose. The aim of this study was to determine the correlation between the pharyngeal airway space and head posture after mandibular setback surgery for mandibular prognathism.Materials and Methods. Serial lateral cephalograms of 37 patients with mandibular prognathism who underwent intraoral vertical ramus osteotomy (IVRO) were evaluated before (T1) and immediately (T2), between 6 weeks and 3 months (T3), and more than 1 year (T4) after surgery. Pairedt-tests and Pearson’s correlation analysis were used to evaluate the postoperative changes in all cephalometric parameters, including the mandible, hyoid, head posture (craniocervical angle), and pharyngeal airway space.Results. The mandible and hyoid were set back by 12.8 mm and 4.9 mm, respectively, at T2. Furthermore, the hyoid showed significant inferior movement of 10.7 mm, with an 8 mm increase in the tongue depth. The upper oropharyngeal airway (UOP) shortened by 4.1 mm, the lower oropharyngeal airway (LOP) by 1.7 mm, and the laryngopharyngeal airway by 2 mm. The craniocervical angle showed a significant increase of 2.8°. UOP and LOP showed a significant correlation with the craniocervical angle at T2 and T4.Conclusions. Our findings conclude that the oropharyngeal airway space is significantly decreased and correlated with a change in the head posture after mandibular setback surgery.

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