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Yoshizaki R, Achiwa M, Inoue H, Nakayama A, Ito Y, Furuta H, Oguma T, Abe A. Changes in the pharyngeal airway space and hyoid bone position after sagittal split ramus osteotomy in mandibular asymmetry: A retrospective cephalometric study. JOURNAL OF ORAL AND MAXILLOFACIAL SURGERY, MEDICINE, AND PATHOLOGY 2023. [DOI: 10.1016/j.ajoms.2023.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Authors’ response. Am J Orthod Dentofacial Orthop 2022; 162:439-440. [DOI: 10.1016/j.ajodo.2022.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 07/17/2022] [Indexed: 11/21/2022]
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Khaghaninejad MS, Khojastehpour L, Danesteh H, Changizi M, Ahrari F. Changes in the pharyngeal airway after different orthognathic procedures for correction of class III dysplasia. Maxillofac Plast Reconstr Surg 2022; 44:23. [PMID: 35678935 PMCID: PMC9184694 DOI: 10.1186/s40902-022-00352-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 05/24/2022] [Indexed: 12/02/2022] Open
Abstract
Objective This study was conducted to compare changes in pharyngeal airway after different orthognathic procedures in subjects with class III deformity. Methods The study included CBCT scans of 48 skeletal class III patients (29 females and 19 males, mean age 23.50 years) who underwent orthognathic surgery in conjunction with orthodontic treatment. The participants were divided into three groups of 16, as follows: Group 1, mandibular setback surgery; group 2, combined mandibular setback and maxillary advancement surgery; and group 3, maxillary advancement surgery. CBCT images were taken 1 day before surgery (T0), 1 day (T1), and 6 months (T2) later. The dimensions of the velopharynx, oropharynx, and hypopharynx were measured in CBCT images. Results In all groups, there was a significant decrease in airway variables immediately after surgery, with a significant reversal 6 months later (P < 0.05). In subjects who underwent maxillary advancement, the airway dimensions were significantly greater at T2 than the T0 time point (P < 0.05), whereas in the mandibular setback and bimaxillary surgery groups, the T2 values were lower than the baseline examination (P < 0.05). The alterations in airway variables were significantly different between the study groups (P < 0.05). Conclusions The mandibular setback procedure caused the greatest reduction in the pharyngeal airway, followed by the bimaxillary surgery and maxillary advancement groups, with the latter exhibiting an actual increase in the pharyngeal airway dimensions. It is recommended to prefer a two-jaw operation instead of a mandibular setback alone for correction of the prognathic mandible in subjects with predisposing factors to the development of sleep-disordered breathing.
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Affiliation(s)
- Mohammad Saleh Khaghaninejad
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Leila Khojastehpour
- Department of Oral and Maxillofacial Radiology, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Hossein Danesteh
- Department of Oral and Maxillofacial Surgery, School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mehdi Changizi
- Oral and Maxillofacial Surgery Resident, Department of Oral and Maxillofacial Surgery, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Farzaneh Ahrari
- Dental Research Center, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.
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Correlation Analysis between Three-Dimensional Changes in Pharyngeal Airway Space and Skeletal Changes in Patients with Skeletal Class II Malocclusion following Orthognathic Surgery. BIOMED RESEARCH INTERNATIONAL 2022; 2022:3995690. [PMID: 35059461 PMCID: PMC8766181 DOI: 10.1155/2022/3995690] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 12/10/2021] [Accepted: 12/16/2021] [Indexed: 12/02/2022]
Abstract
Introduction Studies on the pharyngeal airway space (PAS) changes using three-dimensional computed tomography (CT) have shed more light on patients with Class III than Class II malocclusion. This paper focuses on analyzing the long-term changes in the PAS and evaluating the postoperative association between these PAS and skeletal changes in patients with skeletal Class II malocclusion who have undergone orthognathic surgery. Methods The records of 21 patients with skeletal Class II malocclusion who had undergone orthognathic surgery were included. The anatomical modifications in both jaws, changes in volume, sectional area (SA), minimum sectional area (MSA), and anterior-posterior (AP) and transverse (TV) width in the airway at one month before surgery (T0), and one month (T1) and one year (T2) after surgery were analyzed using CT images. The association between the skeletal and airway changes was evaluated between T0, T1, and T2. Results After surgery, the ANS, A point, and PNS demonstrated significant posterior and superior movement. The B point and the pogonion exhibited substantial anterior and superior movement. The total and inferior oropharyngeal volumes (vol 3, vol 4) notably increased, while the nasopharyngeal volume (vol 1) decreased. The anterior-posterior movement at the ANS and PNS after surgery was significantly associated with the total volume, vol 2, vol 3, SA 1, MSA, and TV width 1, while substantial association with the total volume was found at the pogonion. Conclusion Thus, an ideal treatment plan can be formulated for patients with skeletal Class II malocclusion by considering the postoperative PAS changes.
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Comparison of oropharyngeal airway dimensional changes in patients with skeletal Class II and Class III malocclusions after orthognathic surgery and functional appliance treatment: A systematic review. Saudi Dent J 2021; 33:860-868. [PMID: 34938026 PMCID: PMC8665181 DOI: 10.1016/j.sdentj.2021.09.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 05/11/2021] [Accepted: 09/05/2021] [Indexed: 11/21/2022] Open
Abstract
Objective To compare the dimensional changes in the oropharyngeal airway in patients with skeletal Class II and Class III malocclusion before and after orthognathic surgery and treatment with a functional appliance. Methods The protocol was developed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols (PRISMA-P) and was registered to the International Prospective Register of Systematic Reviews (PROSPERO) under the registration number CRD42020170901. Furthermore, the reporting of the present SR was performed based on the PRISMA checklist. Results The use of removable functional appliances increased the volume of the oropharyngeal airway in patients with skeletal Class II malocclusion. Furthermore, the increase in the volume of the oropharyngeal airway following the removable functional appliance treatment was more than that observed after fixed functional appliance treatment in growing patients. For patients with skeletal Class III malocclusion, who underwent the bimaxillary orthognathic surgery, resulted in no change in the dimensions of the oropharyngeal airway. Conclusion Growing patients who receive removable functional appliance treatment have a more favorable long-term prognosis with regard to the oropharyngeal airway when compared with those who receive fixed functional appliance. Alternatively, in patients aged from (18–22) years with skeletal class III malocclusion Bimaxillary orthognathic surgery was found to be the recomended and superior method of treatment.
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Aljehani D. Review the Impact of Mandibular Setback Surgery for the Correction of Class III Malocclusion on the Upper Airway Space. Open Access Maced J Med Sci 2021. [DOI: 10.3889/oamjms.2021.7298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
AIM: This study aimed to review the scientific evidence related to the effect of mandibular setback surgery for the correction of Class III malocclusion on the changes in volume and anatomical structures’ positions of the upper airway within at least 1 year follow-up.
METHODS: An electronic research was conducted on PubMed, Google scholar, and Elsevier up to April 20, 2021, the inclusion criteria were prospective or retrospective studies aiming to compare the changes in upper airway space following isolated mandibular setback through at least 1 year of follow-up.
RESULTS: A total of 84 studies were retrieved, only 12 studies met the eligibility criteria. Their methods of measurement were using lateral cephalometry, CT, or Cone-beam computed tomography. Most of them showed narrowing in the Pharyngeal airway space, with some variability within the follow-up periods. Impact on the possibility of obstructive sleep apnea (OSA) was discussed in most of the included studies.
CONCLUSION: Narrowing of upper airway volume is associated with isolated mandibular setback surgeries within 1 year of follow-up. However, OSA was not necessarily a consequence. Any predisposing factors for OSA should be considered before isolated mandibular setback surgery.
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Chen CM, Yu TY, Chou ST, Cheng JH, Chen SC, Pan CY, Tseng YC. Changes in Tongue Area, Pharyngeal Area, and Pharyngeal Airway Velocity after Correction of Mandibular Prognathism. J Clin Med 2021; 10:4560. [PMID: 34640582 PMCID: PMC8509434 DOI: 10.3390/jcm10194560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 09/19/2021] [Accepted: 09/24/2021] [Indexed: 02/05/2023] Open
Abstract
This study aimed to investigate the correlation between the amount of mandibular setback, and the related changes of the tongue area, pharyngeal area, and pharyngeal airflow velocity. Twenty-five patients treated for mandibular prognathism, and serial cephalograms were obtained (T1: preoperation, T2: more than one year postoperation). The postoperative area of the tongue, pharyngeal airway space, and pharyngeal airflow velocity were investigated. Statistical analysis was performed with the Student t-test and Pearson correlation. The amount of mandible setback was significant after surgery (12.8 mm; p < 0.001). The pharyngeal area was significantly reduced 115.5 mm2 (p = 0.046). There was a slight reduction of the tongue area (43.2 mm2; p = 0.305) and an increase of pharyngeal airflow velocity (0.3 m/s; p = 0.133). The Pearson correlation coefficient test showed no statistical significance among the amount of horizontal setback and vertical movement of the mandible, such as the reductions in the tongue area, the pharyngeal airway space, and the increase in pharyngeal airflow velocity. Larger amounts of mandibular setback caused a significant reduction of pharyngeal airway area, but without significant changes of the tongue area and pharyngeal airflow velocity.
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Affiliation(s)
- Chun-Ming Chen
- Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan;
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 80756, Taiwan;
| | - Ting-Ying Yu
- School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA;
| | - Szu-Ting Chou
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 80756, Taiwan;
- Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan; (J.-H.C.); (S.-C.C.); (C.-Y.P.)
| | - Jung-Hsuan Cheng
- Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan; (J.-H.C.); (S.-C.C.); (C.-Y.P.)
| | - Shih-Chieh Chen
- Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan; (J.-H.C.); (S.-C.C.); (C.-Y.P.)
| | - Chin-Yun Pan
- Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan; (J.-H.C.); (S.-C.C.); (C.-Y.P.)
| | - Yu-Chuan Tseng
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 80756, Taiwan;
- Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung 80756, Taiwan; (J.-H.C.); (S.-C.C.); (C.-Y.P.)
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Changes in Pharyngeal Airway Space and Craniocervical Angle after Anterior Bimaxillary Subapical Osteotomy. BIOMED RESEARCH INTERNATIONAL 2021; 2021:9978588. [PMID: 34423041 PMCID: PMC8373496 DOI: 10.1155/2021/9978588] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 07/07/2021] [Accepted: 07/23/2021] [Indexed: 11/20/2022]
Abstract
Purpose This study explored the effects of genioplasty (Gep) and anterior subapical osteotomy of the maxilla and mandible (ASOMx+ASOMd) on the pharyngeal airway dimensions of patients with bimaxillary protrusion (BiP). Method Thirty-two patients were divided into 2 groups. Group 1 received ASOMx+ASOMd, and group 2 received ASOMx+ASOMd+Gep. The cephalograms of the patients were collected before surgery and 2 months after surgery. Changes in the landmarks, related cephalometric angles (gonial, SN-GoGn, Y-axis, and SN-C2C4 angles), and 2 pharyngeal airway dimensions (uvulo-pharyngeal airway [UOP] and tongue–pharyngeal airway [TOP]) were analyzed. Results Before surgery, the parameters (incisor superius, incisor inferius, menton, most superior and anterior point of the hyoid bone, tip of the uvula, inferoanterior point on the second cervical vertebra, and inferoanterior point on the fourth cervical vertebra) and measured angles (SNA, SNB, ANB, gonial, SN-GoGn, Y-axis, and C4C2-SN) of both groups showed no significant differences. Following ASOMx, the patients in groups 1 and 2 exhibited a setback by 7.0 and 6.6 mm, respectively. After ASOMd, groups 1 and 2 exhibited 4.9 and 5.3 mm setbacks, respectively. No significant difference in the amount of setback was observed between groups 1 and 2. The postoperative horizontal and vertical positions of Me in group 2 were significantly forward by 6.1 mm and upward by 1.5 mm, respectively. Regarding pharyngeal airway dimensions, TOP was decreased in group 1 (1.7 mm) and group 2 (1.3 mm). In the postoperative Pearson correlation coefficient test, the horizontal and vertical positions of Me showed no significant correlation with TOP in both groups. Therefore, Gep did not prevent the reduction of TOP in group 2. Conclusion After bimaxillary anterior subapical osteotomy, the TOP of patients with BiP was decreased, and this situation was unavoidable, regardless of whether Gep was performed.
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Kim H, Lee KC. Sequential Changes in Pharyngeal Airway Dimensions After Mandibular Setback Surgery and Its Correlation With Postsurgical Stability in Patients With Mandibular Prognathism. J Oral Maxillofac Surg 2021; 79:2540-2547. [PMID: 34453904 DOI: 10.1016/j.joms.2021.07.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 07/18/2021] [Accepted: 07/19/2021] [Indexed: 10/20/2022]
Abstract
PURPOSE This study aimed to evaluate the sequential changes in the pharyngeal airway dimensions after mandibular setback surgery and to verify its correlation with postsurgical mandibular stability in patients with mandibular prognathism. PATIENTS AND METHODS This retrospective study included 28 patients with mandibular prognathism who underwent surgical orthodontic treatment and isolated mandibular setback surgery. Patients who had cone-beam computed tomography before surgery, immediately after surgery, at short-term follow-up (11.8 ± 5.1 months), and long-term follow-up (43.0 ± 13.1 months) were included. Airway dimensions, including distance, minimum cross-sectional area, and airway volume, were measured to evaluate the changes following mandibular setback surgery. With the measurements of postsurgical mandibular relapse, the relationship between sequential changes in airway dimensions and the mandible was verified using correlation analysis. RESULTS Airway dimensions decreased immediately after mandibular setback surgery. The decreased airway dimensions recovered during short-term follow-up and maintained to the long-term follow-up. The mandible was set back 7.7 ± 5.1 mm at pogonion immediately after surgery. Postsurgical skeletal relapse was 1.1 mm at pogonion during short-term follow-up. During long-term follow-up, the mandible moved 0.4 mm anteriorly, which was about 50% of the changes during short-term follow-up. Statistically significant correlations were found between the sequential changes in airway dimensions and the postsurgical skeletal relapse. CONCLUSION The decreased airway dimensions following mandibular setback surgery recovered during short-term follow-up and maintained to the long-term follow-up. Dimensional recovery of the pharyngeal airway was correlated with postsurgical skeletal relapse during the 1-year follow-up period.
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Affiliation(s)
- Hyunmin Kim
- Postgraduate Student, Department of Orthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea
| | - Kyungmin Clara Lee
- Professor, Department of Orthodontics, School of Dentistry, Dental Science Research Institute, Dental 4D Research Institute, Chonnam National University, Gwangju, Korea.
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Abstract
ABSTRACT The aim of this study was to quantify upper airway changes following mandibular orthognathic surgery. Treatment records of 50 patients who underwent mandibular orthognathic surgery were divided into 2 groups, that is, Group 1: Cases treated with Mandibular Advancement Surgery and Group 2: Cases treated with Mandibular Setback Surgery with 25 patients in each group. The Lateral Cephalogram and Acoustic Pharyngometry records of both groups were studied at T0 (01 week before surgery) and T1 (01 year postsurgery) for changes in linear airway measurements (Nasopharyngeal Airway Space - NAS, Superior Airway Space - SAS, Posterior Airway Space - PAS and Hypopharyngeal Airway Space (HAS)), hyoid bone position (Mandibular Plane Hyoid distance), mean area and mean volume. The percentage change and change in these parameters per millimeter advancement or setback of mandible at T1 was calculated. A significant increase in linear airway parameters (SAS and PAS); decrease in hyoid distance; and increase in volume and area of upper airway was observed at T1 in Group 1 and reverse was observed in Group 2. The change in airway parameters (SAS, PAS, mean volume and area) was more significant in Group 1 as compared to Group 2. In the current airway centric approach, meticulous assessment and prediction of long-term airway changes post surgery should be an integral part of ortho-surgical diagnosis and treatment planning and suitable modifications in the treatment plan must be made to cater for any potential adverse effects on airway.
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Importance in the Occurrence Distribution of Minimum Oropharyngeal Cross-Sectional Area in the Different Skeletal Patterns Using Cone-Beam Computed Tomography. BIOMED RESEARCH INTERNATIONAL 2021; 2021:5585629. [PMID: 33997021 PMCID: PMC8116163 DOI: 10.1155/2021/5585629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 04/28/2021] [Indexed: 11/25/2022]
Abstract
Purpose Obstructive sleep apnea is a condition involving repetitive partial or complete collapse of the pharyngeal airway, especially in patient with mandibular hypoplasia. The present study investigated the differences between the volume of the oropharyngeal airway and the minimum axial area in three skeletal patterns through the use of cone-beam computed tomography (CBCT). Materials and Methods CBCT scans of 147 patients were collected to measure the upper oropharyngeal airway volume (UOV), lower oropharyngeal airway volume (LOV), upper oropharyngeal airway area (UOA), minimum upper oropharyngeal airway area (MUOA), lower oropharyngeal airway area (LOA), minimum lower oropharyngeal airway area (MLOA), anatomical structures (orbitale, Or; porion, Po; pogonion, Pog; hyoid, H; second cervical vertebra, C2; fourth cervical vertebra, C4), and relevant angles. Statistical analysis was performed using analysis of variance and Pearson's test. Results Compared with patients in Class II, those in Class III and Class I exhibited a significantly anterior position of H and Pog. The vertical positions of H and Pog revealed no significant difference between the three skeletal patterns. Patients in skeletal Class III exhibited significantly larger oropharyngeal area (UOA, MUOA, LOA, MLOA) and oropharyngeal airway (UOV and LOV) than those in skeletal Class II did. The horizontal position of Pog had a moderately significant correlation with UOA (r = 0.471) and MUOA (r = 0.455). Conclusion Patients in skeletal Class II had significantly smaller oropharyngeal airway areas and volumes than those in Class III did. The minimum oropharyngeal cross-sectional area had a 67% probability of occurrence in the upper oropharyngeal airway among patients in Class I and Class II and a 50% probability of occurrence among patients in Class III.
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The Effect of Orthognathic Surgery on the Hyoid Bone Position in Skeletal Class III Patients: An Evaluation Using Cephalometric Analysis. World J Plast Surg 2021. [DOI: 10.52547/wjps.10.2.46] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Velopharyngeal Space Assessment in Patients Undergoing Le Fort 1 Maxillary Advancement. PLASTIC AND RECONSTRUCTIVE SURGERY-GLOBAL OPEN 2020; 8:e3232. [PMID: 33299700 PMCID: PMC7722571 DOI: 10.1097/gox.0000000000003232] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 08/07/2020] [Indexed: 12/04/2022]
Abstract
Background: The effects of maxillary advancement on velopharyngeal anatomy have primarily been studied using lateral cephalometric radiographs. However, with recent advances in orthognathic surgery, there is an increased need for more detailed and precise imaging such as computerized tomographic (CT) scan reconstructions, to help in surgical planning and to measure outcomes. The purpose of this study was to compare the pre- and post-operative velopharyngeal anatomic configuration modifications as measured on CT scans. Methods: This is a retrospective cohort study of 44 patients with and without cleft palate who were treated with maxillary advancement. The pre- and post-operative CT scans were compared with respect to pre-established landmarks. Linear distances, cross-sectional areas, and volumes were measured using 3-dimensional CT scan reconstructions. Results: For the linear distances measured, a statistically significant difference was found when comparing the pre- and post-operative measures of the narrowest part of the nasopharynx and the narrowest part of the retropalatal airway space (P = 0.001 and 0.026, respectively). Retropalatal cross-sectional areas, nasopharyngeal cross-sectional areas, and the volumetric assessment of the nasopharyngeal space showed no statistically significant differences when comparing pre- and post-operative scans (P < 0.05). Mean changes in the measures did not differ over time (pre- and post-operative) depending on whether there was a prior history of cleft palate repair. Conclusions: Although structural modifications of the pharyngeal space are inherent to maxillary advancement, its surface area and volume do not significantly change. The use of 3-dimensional reconstruction using CT scans should be the first choice for evaluation of the upper airway.
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Tseng YC, Tsai FC, Chou ST, Hsu CY, Cheng JH, Chen CM. Evaluation of pharyngeal airway volume for different dentofacial skeletal patterns using cone-beam computed tomography. J Dent Sci 2020; 16:51-57. [PMID: 33384778 PMCID: PMC7770282 DOI: 10.1016/j.jds.2020.07.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 07/16/2020] [Indexed: 11/21/2022] Open
Abstract
Background/purpose Understanding of the three-dimensional airway space in three skeletal patterns is important in orthodontic treatment. This study investigated differences between the volume of pharyngeal airway sections and the smallest cross-sectional area in three skeletal patterns by using cone-beam computed tomography (CBCT). Materials and methods The 90 patients were collected to measure total pharyngeal airway volume (TP), velopharyngeal airway volume (VP), glossopharyngeal airway volume (GP), oropharyngeal airway volume (OP), hypopharyngeal airway volume (HP), and the smallest cross-sectional areas (SCA) of the upper respiratory tract as well as other relevant anatomical structures. The mean values differences between classes were analyzed using ANOVA. Pearson's test was used to compare classes in terms of the correlations between different factors. Results Patients in skeletal classes I and III exhibited significantly higher SCA values (322.6 mm2and 344.5 mm2 respectively) than those in skeletal class II (240.8 mm2). Subjects from skeletal classes I and III exhibited significantly higher values of VP, HP, and OP than those in skeletal class II. Skeletal classes I and III exhibited significantly higher TP values (31190.1 mm3 and 30696.2 mm3, respectively) than those in skeletal class II (22386.0 mm3). Non-significant relationships were discovered between pharyngeal airway and skeletal pattern. Conversely, significant relationships were found between TP and gender, ANB, SNB, hyoid and pogonion positions. Conclusion The skeletal class II has smaller airway volume than those in skeletal class I and III. The pharyngeal airway volumes could serve as a guide in differentiating the different skeletal classes in clinical settings.
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Affiliation(s)
- Yu-Chuan Tseng
- School of Dentistry, Kaohsiung Medical University, Kaohsiung, Taiwan.,Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Feng-Chun Tsai
- School of Dentistry, Kaohsiung Medical University, Kaohsiung, Taiwan.,Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Szu-Ting Chou
- School of Dentistry, Kaohsiung Medical University, Kaohsiung, Taiwan.,Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Chung-Yao Hsu
- School of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan.,Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Jung-Hsuan Cheng
- School of Dentistry, Kaohsiung Medical University, Kaohsiung, Taiwan.,Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Chun-Ming Chen
- School of Dentistry, Kaohsiung Medical University, Kaohsiung, Taiwan.,Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
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Kim SH, Choi SK. Changes in the hyoid bone, tongue, and oropharyngeal airway space after mandibular setback surgery evaluated by cone-beam computed tomography. Maxillofac Plast Reconstr Surg 2020; 42:27. [PMID: 32821741 PMCID: PMC7423819 DOI: 10.1186/s40902-020-00271-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 08/03/2020] [Indexed: 11/10/2022] Open
Abstract
Background Mandibular setback surgery can change the position of the mandible which improves occlusion and facial profile. Surgical movement of the mandible affects the base of the tongue, hyoid bone, and associated tissues, resulting in changes in the pharyngeal airway space. The aim of this study was to analyze the 3-dimensional (3D) changes in the hyoid bone and tongue positions and oropharyngeal airway space after mandibular setback surgery. Methods A total of 30 pairs of cone-beam computed tomography (CBCT) images taken before and 1 month after surgery were analyzed by measuring changes in the hyoid bone and tongue positions and oropharyngeal airway space. The CBCT images were reoriented using InVivo 5.3 software (Anatomage, San Jose, USA) and landmarks were assigned to establish coordinates in a three-dimensional plane. The mean age of the patients was 21.7 years and the mean amount of mandibular setback was 5.94 mm measured from the B-point. Results The hyoid bone showed significant posterior and inferior displacement (P < 0.001, P < 0.001, respectively). Significant superior and posterior movements of the tongue were observed (P < 0.05, P < 0.05, respectively). Regarding the velopharyngeal and glossopharyngeal spaces, there were significant reductions in the volume and minimal cross-sectional area (P < 0.001). The anteroposterior and transverse widths of the minimal cross-sectional area were decreased (P < 0.001, P < 0.001, respectively). In addition, the amount of mandibular setback positively correlated with the amount of posterior and inferior movement of the hyoid bone (P < 0.05, P < 0.05, respectively). Conclusion There were significant changes in the hyoid bone, tongue, and airway space after mandibular setback surgery.
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Affiliation(s)
- Seon-Hye Kim
- Department of Orthodontics, School of Dentistry, Wonkwang University, Iksan, Korea
| | - Sung-Kwon Choi
- College of dentistry, Graduate School of Wonkwang University, Iksan, Korea
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The Envelope of Segmental Movement and Airway Changes After Mandibular Anterior Subapical Osteotomy in Skeletal Class II Protrusion Patients. J Craniofac Surg 2020; 31:668-672. [DOI: 10.1097/scs.0000000000006159] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Skeletal and airway stability after mandibular setback in patients with mandibular prognathism: A systematic review. Saudi Dent J 2020; 33:169-176. [PMID: 34025077 PMCID: PMC8117365 DOI: 10.1016/j.sdentj.2020.02.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 02/18/2020] [Accepted: 02/23/2020] [Indexed: 11/24/2022] Open
Abstract
Aim To perform a systematic review to answer the clinical question “What are the longitudinal skeletal and airway changes after mandibular setback orthognathic procedures?” Materials and methods A systematic search including computer search of different databases with specific keywords, manual search through three international journals and reference list search was performed. Articles that were reporting the skeletal and airway changes after mandibular setback orthognathic procedures were evaluated with five predetermined criteria. Results Six articles with a total of 217 patients entered the final review. All were rated to be of moderate bias risk. Four studies evaluated the skeletal and airway changes using two-dimensional (lateral) cephalometric radiographic imaging, whereas the other two studies used three-dimensional imaging with cone-beam computed tomography. In the two-dimensional studies, skeletal relapses from T0 (immediate postoperative) to T1 (postoperative 1–6 months) ranged from −2.14 mm to 0.30 mm, whereas skeletal relapses from T1 to T2 (postoperative 1 year) ranged from −0.90 mm to 1.23 mm. In the three-dimensional studies, skeletal relapse from T1 to T2 ranged from −0.26 mm to 1.53 mm. All included studies reported that there were no significant skeletal relapses after mandibular setback procedures. Regarding airway changes, airway changes from preoperative to T0/T1 ranged from −0.30 mm to −2.32 mm in the two-dimensional studies. Airway changes from T0 to T1 ranged from −0.70 mm to −1.63 mm, whereas airway changes from T1 to T2 ranged from 0.11 mm to 0.60 mm, respectively. Conclusions This systematic review showed there was insignificant skeletal relapse after mandibular setback orthognathic procedures. It was noted a small increase of the airway over the first post-operative year in studies using 2-dimensional radiography. However, such finding was not consistent in studies using 3-dimensional imaging with volumetric analysis of the airway changes.
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Yang H, Jung YE, Kwon I, Lee JY, Hwang S. Airway changes and prevalence of obstructive sleep apnoea after bimaxillary orthognathic surgery with large mandibular setback. Int J Oral Maxillofac Surg 2020; 49:342-349. [DOI: 10.1016/j.ijom.2019.07.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Revised: 05/19/2019] [Accepted: 07/23/2019] [Indexed: 11/25/2022]
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Postoperative Skeletal Stability and Pharyngeal Airway: Counterclockwise versus Clockwise Rotation during Mandibular Setback Surgery. BIOMED RESEARCH INTERNATIONAL 2020; 2020:3283080. [PMID: 32083127 PMCID: PMC7011342 DOI: 10.1155/2020/3283080] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Revised: 12/19/2019] [Accepted: 01/07/2020] [Indexed: 11/23/2022]
Abstract
Purpose To compare the effects of counterclockwise rotation (CCR) and clockwise rotation (CR) of the mandible on the pharyngeal airway during mandibular setback surgery. Materials and Methods. Serial cephalograms of 40 patients with mandibular prognathism, including 20 who underwent CCR and 20 who underwent CR, were taken at the following time intervals: preoperatively (T1), immediately postoperatively (T2), >1 year after surgery (T3), final surgical changes (T31), postoperative stability (T32), and immediate surgical change (T21). Changes in menton (Me) and hyoid (H) positions, soft palate width, soft palate length, soft palate angle and craniovertebral angle (C2C4-SN), and pharyngeal airway spaces (nasal pharyngeal airway (NOP), uvula pharyngeal airway (UOP), tongue pharyngeal airway (TOP), and epiglottis pharyngeal airway (EOP)) were evaluated. Results The mean Me (T31) setback for CCR and CR was 12.56 and 13.06 mm, respectively, with 2.41 mm upward and 3.29 mm downward, respectively. The vertical Me position of CR exhibited significant downward movement compared with that of CCR. The mean H setback results for CCR and CR were 4.42 and 5.75 mm, respectively, with 1.47 mm downward and 2.97 mm downward, respectively. The C4C2-SN angles for CCR and CR increased by 2.68° and 3.65°, respectively, whereas their palatal angles increased by 2.35° and 5.25°, respectively. Pearson's correlation analysis (T31) revealed that for CCR, no pharyngeal airway spaces were significantly correlated with any measured variables. In CR, NOP was significantly correlated (r = 0.58) with the vertical Me position. Significant relapse (T32) was observed after CR in the horizontal (r = 0.58) with the vertical Me position. Significant relapse (T32) was observed after CR in the horizontal (r = 0.58) with the vertical Me position. Significant relapse (T32) was observed after CR in the horizontal ( Conclusion Pharyngeal airway space narrowed postoperatively, and its patency was appropriately maintained through natural physiological regulation of the craniovertebral angle (C2C4-SN). Significant postoperative relapse was correlated with CR.
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Shirazawa Y, Iwasaki T, Ooi K, Kobayashi Y, Yanagisawa-Minami A, Oku Y, Yokura A, Ban Y, Suga H, Kawashiri S, Yamasaki Y. Relationship between pharyngeal airway depth and ventilation condition in mandibular setback surgery: A computational fluid dynamics study. Orthod Craniofac Res 2020; 23:313-322. [PMID: 32056328 DOI: 10.1111/ocr.12371] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 02/07/2020] [Accepted: 02/10/2020] [Indexed: 12/27/2022]
Abstract
OBJECTIVES This study aimed to determine the anteroposterior depth (APD) of the pharyngeal airway (PA) where post-operative PA obstruction was predicted, using computer fluid dynamics (CFD), in order to prevent obstructive sleep apnoea after mandibular setback surgery. SETTINGS AND SAMPLE POPULATION Nineteen skeletal Class III patients (8 men; mean age, 26.7 years) who required mandibular setback surgery had computed tomography images taken before and 6 months after surgery. METHODS The APD of each site of the four cross-sectional reference planes (retropalatal airway [RA], second cervical vertebral airway, oropharyngeal airway and third cervical vertebral airway) were measured. The Maximum negative pressure (Pmax) of the PA was measured at inspiration using CFD, based on a three-dimensional PA model. Intersite differences were determined using analysis of variance and the Friedman test with Bonferroni correction. The relationship between APD and Pmax was evaluated by Spearman correlation coefficients and non-linear regression analysis. RESULTS The smallest PA site was the RA. Pmax was significantly correlated with the APD of the RA (rs = .628, P < .001). The relationship between Pmax and the APD-RA was fitted to a curve, which showed an inversely proportional relationship of Pmax to the square of the APD-RA. Pmax substantially increased even with a slight reduction of the APD-RA. In particular, when the APD-RA was 7 mm or less, Pmax increased greatly, suggesting that PA obstruction was more likely to occur. CONCLUSIONS The results of this study suggest that APD-RA is a useful predictor of good PA ventilation after surgery.
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Affiliation(s)
- Yoshito Shirazawa
- Department of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City, Japan
| | - Tomonori Iwasaki
- Department of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City, Japan
| | - Kazuhiro Ooi
- Department of Oral and Maxillofacial Surgery, School of Medical Science, Kanazawa University Graduate, Kanazawa-City, Japan
| | - Yutaka Kobayashi
- Department of Oral and Maxillofacial Surgery, School of Medical Science, Kanazawa University Graduate, Kanazawa-City, Japan
| | - Ayaka Yanagisawa-Minami
- Department of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City, Japan
| | - Yoichiro Oku
- Department of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City, Japan
| | - Anna Yokura
- Department of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City, Japan
| | - Yuusuke Ban
- Department of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City, Japan
| | - Hokuto Suga
- Department of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City, Japan
| | - Shuichi Kawashiri
- Department of Oral and Maxillofacial Surgery, School of Medical Science, Kanazawa University Graduate, Kanazawa-City, Japan
| | - Youichi Yamasaki
- Department of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima-City, Japan
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An JH, Park SB, Choi YK, Lee SH, Kim KB, Kim YI. Cone-Beam Computed Tomography Evaluation of Pharyngeal Airway Space Changes After Bimaxillary Orthognathic Surgery in Patients With Class III Skeletal Deformities: A 6-Year Follow-Up Study. J Oral Maxillofac Surg 2019; 77:2534-2544. [DOI: 10.1016/j.joms.2019.07.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 07/24/2019] [Accepted: 07/25/2019] [Indexed: 10/26/2022]
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Lee K, Hwang SJ. Change of the upper airway after mandibular setback surgery in patients with mandibular prognathism and anterior open bite. Maxillofac Plast Reconstr Surg 2019; 41:51. [PMID: 31824889 PMCID: PMC6877677 DOI: 10.1186/s40902-019-0230-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 09/23/2019] [Indexed: 11/10/2022] Open
Abstract
Purpose It has been reported before that the amount of pharyngeal airway space (PAS) significantly decreases following mandibular setback (MS) surgery in patients with mandibular prognathism (MP). Further, MP patients with an anterior open-bite (AOB) presentation may show a larger decrease in PAS compared with those without AOB. However, studies on postoperative PAS changes in MP patients with AOB remain rare. This study sought to evaluate changes in PAS and hyoid bone positioning following MS surgery in MP patients with and without AOB. Patients and methods Twenty patients who underwent two jaw surgery involving MS movement were included. Patients were divided into a non-AOB group (n = 10; overbite > 2 mm) and an AOB group (n = 10; overbite < - 4 mm). Three-dimensional changes in PAS and hyoid bone positioning were compared and statistically evaluated pre- and postoperatively using computed tomography (CT). Results The mean magnitude of MS was 6.0 ± 2.8 mm and 5.6 ± 3.2 mm in the non-AOB group and AOB group, respectively. The oropharyngeal volume and upper hypopharyngeal volume were significantly reduced after surgery in both the groups (p = 0.006 and p = 0.003), while the retroglossal cross-sectional area was significantly reduced only in the AOB group (p = 0.028). Although the AOB group showed a larger decrease in PAS, the difference was not statistically significant between the groups. The position of the hyoid bone showed significant posterior and inferior displacement only in the AOB group, while the vertical displacement of the hyoid bone showed a statistically significant difference between the two groups. Conclusion PAS was significantly decreased after MS in both the groups, while only the AOB group presented a statistically significant reduction in the retroglossal cross-sectional area. Vertical displacement of the hyoid bone showed a statistically significant difference between the groups, while the PAS change was not. Surgeons should be aware of potential postoperative airway problems that may arise when performing MS surgeries.
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Affiliation(s)
- Kyungjin Lee
- 1Department of Oral and Maxillofacial Surgery, School of Dentistry, Seoul National University, Seoul, Republic of Korea
| | - Soon Jung Hwang
- HSJ Dental Clinic for Oral and Maxillofacial Surgery, Wannam Building 2,3F, 349 Gangnam-daero, Seocho-gu, Seoul, 06626 Republic of Korea
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Havron AG, Aronovich S, Shelgikar AV, Kim HL, Conley RS. 3D Airway changes using CBCT in patients following mandibular setback surgery ± maxillary advancement. Orthod Craniofac Res 2019; 22 Suppl 1:30-35. [PMID: 31074136 DOI: 10.1111/ocr.12291] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 12/07/2018] [Indexed: 12/01/2022]
Abstract
INTRODUCTION The aim of this study was to determine the 3D airway changes that occur following mandibular setback surgery alone vs bimaxillary surgery in patients with similar skeletal start forms. SETTING AND SAMPLE POPULATION The University of Michigan School of Dentistry and Medical Center. A total of 85 patients undergoing mandibular setback with or without simultaneous maxillary advancement. MATERIALS AND METHODS A retrospective evaluation of pre- and post-surgical CBCT scans for patients undergoing mandibular setback surgery alone (14) vs bimaxillary surgery (71) was performed. Cross-sectional evaluation at standardized locations, minimum cross section and volumetric analysis were performed (Dolphin Imaging & Management Solutions). RESULTS Patients who underwent mandibular setback surgery alone showed a statistically significant average increase of 47.5 mm2 in minimum axial area. Patients who underwent bimaxillary surgery showed a statistically significant increase in airway volume, minimum axial area, location of minimum axial area, and axial area at the retropalatal and retroglossal regions. CONCLUSIONS The results demonstrate that the mandible can be setback safely without decreasing airway dimensions. In borderline OSA patients, bimaxillary surgery remains the preferred approach due to the larger airway increases observed. Long-term follow-up with polysomnography must be conducted to determine the full functional implications of both procedures.
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Affiliation(s)
- Andrew G Havron
- Department of Orthodontics and Pediatric Dentistry, University of Michigan, Ann Arbor, Michigan
| | - Sharon Aronovich
- Department of Oral and Maxillofacial Surgery, University of Michigan, Ann Arbor, Michigan
| | - Anita V Shelgikar
- Department of Neurology, University of Michigan, Ann Arbor, Michigan
| | | | - R Scott Conley
- Department of Orthodontics, University at Buffalo, Buffalo, New York
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Souza Pinto GND, Iwaki Filho L, Previdelli ITDS, Ramos AL, Yamashita AL, Stabile GAV, Stabile CLP, Iwaki LCV. Three-dimensional alterations in pharyngeal airspace, soft palate, and hyoid bone of class II and class III patients submitted to bimaxillary orthognathic surgery: A retrospective study. J Craniomaxillofac Surg 2019; 47:883-894. [DOI: 10.1016/j.jcms.2019.03.015] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2018] [Revised: 02/11/2019] [Accepted: 03/11/2019] [Indexed: 11/29/2022] Open
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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 2019; 2019:5012037. [PMID: 31008106 PMCID: PMC6441503 DOI: 10.1155/2019/5012037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 02/06/2019] [Accepted: 02/28/2019] [Indexed: 12/03/2022]
Abstract
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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Sahoo N, Roy ID, Kulkarni V. Mandibular setback and its effects on speech. ORAL AND MAXILLOFACIAL SURGERY CASES 2019. [DOI: 10.1016/j.omsc.2018.10.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Karan NB, Kahraman S. Evaluation of posterior airway space after setback surgery by simulation. Med Biol Eng Comput 2019; 57:1145-1150. [PMID: 30673976 DOI: 10.1007/s11517-018-1943-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 12/10/2018] [Indexed: 11/28/2022]
Abstract
The possible negative outcomes of mandibular setback surgery (MSS) on the upper airway (UA) have become an important issue in recent years. The purpose of the present study was to compare the different amounts of MSS and to confirm the accepted maximum amount of mandibular setback by using Computational Fluid Dynamics (CFD) method. An anatomically similar UA model was constructed from magnetic resonance images of a systemically healthy individual. Two out of six models were kept as control models and the remaining four models were created to represent MSS scenarios with different amounts to correct Class III skeletal abnormality. The airflow was assumed laminar, incompressible, and the surrounding soft tissue was assumed to be linear elastic. The sixth model that was representative of 15 mm of MSS showed statistically significant differences from the other models (p < 0.05). No significant differences were observed among other models in terms of all the parameters (p > 0.05). CFD has been recently used in researches by modeling the UA flow; however, to the best of our knowledge, none of the studies have proved the maximum limits of MSS amounts with this technique. Graphical abstract ᅟ.
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Affiliation(s)
- Nazife Begum Karan
- Department of Oral and Maxillofacial Surgery, Recep Tayyip Erdoğan University, Rize, Turkey.
| | - Sevil Kahraman
- Department of Oral and Maxillofacial Surgery, Gazi University, Ankara, Turkey
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Upper airway morphologic changes after mandibular setback surgery in skeletal class III malocclusion patients measured using cone beam computed tomography superimposition. Int J Oral Maxillofac Surg 2018; 47:1405-1410. [DOI: 10.1016/j.ijom.2018.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2017] [Revised: 02/28/2018] [Accepted: 05/07/2018] [Indexed: 11/23/2022]
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Carneiro Júnior JT, Voss de Oliveira D, Goodday R. Maxillary stability following Le Fort I osteotomy using prebent plates and wire fixation in patients undergoing surgery for OSAS. J Craniomaxillofac Surg 2018; 46:1448-1454. [PMID: 30196854 DOI: 10.1016/j.jcms.2018.05.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Revised: 04/29/2018] [Accepted: 05/29/2018] [Indexed: 11/30/2022] Open
Abstract
The purpose of this study was to analyze the stability of Le Fort I maxillary advancement in the vertical and horizontal directions using a combination of wire and rigid fixation in patients undergoing surgery to treat obstructive sleep apnea (OSA). Wire osteosynthesis can be performed quicker and at a reduced cost. The lateral cephalograms of 21 patients were evaluated preoperatively (T0), immediately postoperatively (T1), and at least 6 months postoperatively (T2). Four cephalometric points were used to measure movement in the horizontal and vertical directions. Mean values were determined, and data were statistically analyzed by ANOVA to determine differences between time points. Of the four points analyzed, the average maxillary advancement in the horizontal direction was 7.48 mm and the relapse was 0.56 mm with absence of statistically significant differences between the measurements taken (T1) and (T2). There was a 5% probability of error in the vertical movements at the points I and posterior nasal spine. The combination of two pre-bent plates in piriform aperture with osteosynthesis using surgical steel wires in the zygomatic buttress in patients undergoing maxillary surgery for OSA stabilized the large horizontal maxillary advancements and enhanced vertical stability in the first molar and A point regions.
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Affiliation(s)
- José Thiers Carneiro Júnior
- Federal University of Pará, (Head of the institution: Emmanuel Zagury Tourinho, PhD), Augusto Corrêa, 01, Guamá, CEP: 66075-110, Belém, PA, Brazil.
| | - Douglas Voss de Oliveira
- Federal University of Pará, (Head of the institution: Emmanuel Zagury Tourinho, PhD), Augusto Corrêa, 01, Guamá, CEP: 66075-110, Belém, PA, Brazil.
| | - Reginald Goodday
- Department of Oral and Maxillofacial Sciences, (Head of the institution: Dr. Ben Davis, DDS), Dalhousie University, 5981, University Ave, Halifax, NS, Canada.
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The Relationship Between Cephalogram Analysis and Oxygen Desaturation Index During Sleep in Patients Submitted for Mandibular Setback Surgery. J Craniofac Surg 2018; 29:e375-e380. [DOI: 10.1097/scs.0000000000004386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Gender differences in morphological and functional outcomes after mandibular setback surgery. J Craniomaxillofac Surg 2018; 46:887-892. [PMID: 29709333 DOI: 10.1016/j.jcms.2018.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 03/19/2018] [Accepted: 04/04/2018] [Indexed: 11/23/2022] Open
Abstract
PURPOSE The aim of this study was to examine and compare morphological and functional outcomes after either isolated mandibular setback or bimaxillary surgery in males and females. MATERIALS AND METHODS A retrospective study was done on 52 patients, in whom surgical correction for mandibular prognathism was performed either by isolated mandibular setback (30 cases) or by bimaxillary surgery (22 cases). Morphological changes were studied using cephalograms and functional changes studied using impulse oscillometry (IOS) taken before surgery (T0), 3 months (T1) and 1 year after surgery (T2). Also 3% oxygen desaturation index (ODI) was measured at T0 and T2. RESULT Posterior airway space decreased significantly in both groups and both sexes but more so in males after mandibular setback surgery and in females after bimaxillary surgery. Changes in supine R20 (central airway resistance at 20 Hz) and supine R5 (total airway resistance at 5 Hz) in IOS statistically significantly increased in the period T0-T1 in males compared with females after mandibular setback surgery (p < 0.05). CONCLUSION Gender dimorphism is present according to morphological and functional outcomes, with males at a higher risk for obstructive sleep apnea (OSA) after mandibular setback surgery and females after bimaxillary surgery; however, compensatory changes act as a barrier against this.
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Irani SK, Oliver DR, Movahed R, Kim YI, Thiesen G, Kim KB. Pharyngeal airway evaluation after isolated mandibular setback surgery using cone-beam computed tomography. Am J Orthod Dentofacial Orthop 2018; 153:46-53. [DOI: 10.1016/j.ajodo.2017.05.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 05/01/2017] [Accepted: 05/01/2017] [Indexed: 10/18/2022]
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Azevêdo MS, Machado AW, Barbosa IDS, Esteves LS, Rocha VÁC, Bittencourt MAV. Evaluation of upper airways after bimaxillary orthognathic surgery in patients with skeletal Class III pattern using cone-beam computed tomography. Dental Press J Orthod 2017; 21:34-41. [PMID: 27007759 PMCID: PMC4816583 DOI: 10.1590/2177-6709.21.1.034-041.oar] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 08/04/2015] [Indexed: 11/22/2022] Open
Abstract
Introduction: It has been suggested that mandibular setback surgery, combined or not with maxillary advancement as a treatment alternative for patients with mandibular prognathism, can induce changes in upper airway space (UAS). Therefore, this study aimed to assess the response of the upper airway in the oropharynx region of patients with Class III skeletal pattern that underwent bimaxillary orthognathic surgery (maxillary advancement and mandibular setback) combined with mentoplasty. Material and Methods: The sample comprised 26 cone-beam computed tomography (CBCT) scans of 13 patients. The examination was taken before and after surgery. UAS volume, sagittal area, length and minimal axial area with its width, depth and location, were measured with the aid of Dolphin ImagingTMsoftware version 11.5 Premium. Data were statistically treated by applying Shapiro-Wilk test and Student's paired t-test, considering as statistically significant the results of which p-value was lower than 0.05. Results: No statistically significant differences were found in any measurements evaluated. Conclusions: No significant changes were observed in the oropharynx after bimaxillary orthognathic surgery and mentoplasty.
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Affiliation(s)
| | - Andre Wilson Machado
- Department of Orthodontics, Universidade Federal da Bahia, Salvador, Bahia, Brazil
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Tseng YC, Wu JH, Chen CM, Hsu KJ. Correlation between change of tongue area and skeletal stability after correction of mandibular prognathism. Kaohsiung J Med Sci 2017; 33:302-307. [PMID: 28601235 DOI: 10.1016/j.kjms.2017.03.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 03/03/2017] [Indexed: 11/24/2022] Open
Abstract
The purpose of this study was to investigate the correlation between postoperative stability and a change in tongue area after treatment of mandibular prognathism. Twenty-six patients, who were treated for mandibular prognathism using intraoral vertical ramus osteotomy, were evaluated cephalometrically. A set of three standardized lateral cephalograms were obtained from each participant preoperatively (T1), immediately postoperatively (T2), and after 2 years postoperatively (T3). Student t test and Pearson correlation coefficient were used for statistical analysis. Immediately after the surgery (T12), the setback of the menton (Me) was 12.9 mm (p<0.001) and the tongue area had significantly increased to 105.8 mm2 (p=0.047). At a 2-year follow-up to examine postsurgical stability (T23), the Me exhibited a forward movement of 0.6 mm (p=0.363) and the tongue area had significantly decreased to 124.3 mm2 (p=0.004). Pearson correlation coefficient test revealed no statistical significance between postoperative stability and change in tongue area. The tongue area significantly increased during the T12 period and decreased during the T23 period. There is no significant correlation between postoperative skeletal relapse and a change in tongue area.
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Affiliation(s)
- Yu-Chuan Tseng
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Ju-Hui Wu
- Department of Oral Hygiene, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Family Dentistry, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Chun-Ming Chen
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Kun-Jung Hsu
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Family Dentistry, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan.
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Vaezi T, Zarch SHH, Eshghpour M, Kermani H. Two-dimensional and volumetric airway changes after bimaxillary surgery for class III malocclusion. J Korean Assoc Oral Maxillofac Surg 2017; 43:88-93. [PMID: 28462192 PMCID: PMC5410433 DOI: 10.5125/jkaoms.2017.43.2.88] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 11/07/2016] [Accepted: 11/19/2016] [Indexed: 11/07/2022] Open
Abstract
OBJECTIVES Any change in maxilla and mandible position can alter the upper airway, and any decrease in the upper airway can cause sleep disorders. Thus, it is necessary to assess airway changes after repositioning of the maxilla and mandible during orthognathic surgery. The purpose of this study was to evaluate linear and volumetric changes in the upper airway after bimaxillary surgery to correct class III malocclusion via cone-beam computed tomography (CBCT) and to identify correlations between linear and volumetric changes. MATERIALS AND METHODS This was a prospective cohort study. CBCTs from 10 class III patients were evaluated before surgery and three months after. The Wilcoxon one-sample test was used to evaluate the differences in measurements before and after surgery. Spearman's rank correlation coefficient was used to test the correlation between linear and volumetric changes. RESULTS The results show that the nasopharyngeal space increased significantly, and that this increase correlated with degree of maxillary advancement. No significant changes were found in volumes before and after surgery. A correlation was found between linear and volumetric oropharyngeal changes. CONCLUSION Bimaxillary surgical correction of class III malocclusion did not cause statistically significant changes in the posterior airway space.
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Affiliation(s)
- Toraj Vaezi
- Oral and Maxillofacial Surgeon, Maxillofacial Trauma Fellow, Sina Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Hossein Hosseini Zarch
- Department of Oral and Maxillofacial Radiology, Dental Material Research Center and School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Majid Eshghpour
- Oral and Maxillofacial Surgeon, Mashhad University of Medical Sciences Dental School, Mashhad, Iran
| | - Hamed Kermani
- Oral and Maxillofacial Surgeon, Mashhad University of Medical Sciences Dental School, Mashhad, Iran.,Oral and Maxillofacial Diseases Research Center, Mashhad, Iran
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Yajima Y, Oshima M, Iwai T, Kitajima H, Omura S, Tohnai I. Computational fluid dynamics study of the pharyngeal airway space before and after mandibular setback surgery in patients with mandibular prognathism. Int J Oral Maxillofac Surg 2017; 46:839-844. [PMID: 28412180 DOI: 10.1016/j.ijom.2017.03.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 01/21/2017] [Accepted: 03/21/2017] [Indexed: 10/19/2022]
Abstract
The purpose of this study was to investigate the relationship between the pressure drop in the pharyngeal airway space (ΔPPAS) and the minimum cross-sectional area (minCSA) of the pharyngeal airway before and after mandibular setback surgery using computational fluid dynamics, in order to prevent iatrogenic obstructive sleep apnoea. Eleven patients with mandibular prognathism underwent bilateral sagittal split osteotomy for mandibular setback. Three-dimensional models of the upper airway were reconstructed from preoperative and postoperative computed tomography images, and simulations were performed using computational fluid dynamics. ΔPPAS and the minCSA of the pharyngeal airway were calculated, and the relationship between them was evaluated by non-linear regression analysis. In all cases, the minCSA was found at the level of the velopharynx. After surgery, ΔPPAS increased significantly and the minCSA decreased significantly. The non-linear regression equation expressing the relationship between these variables was ΔPPAS=3.73×minCSA-2.06. When the minCSA was <1cm2, ΔPPAS increased greatly. The results of this study suggest that surgeons should consider bimaxillary orthognathic surgery rather than mandibular setback surgery to prevent the development of iatrogenic obstructive sleep apnoea when correcting a skeletal class III malocclusion.
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Affiliation(s)
- Y Yajima
- Department of Oral and Maxillofacial Surgery, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa, Japan
| | - M Oshima
- Institute of Industrial Science, The University of Tokyo, Tokyo, Japan
| | - T Iwai
- Department of Oral and Maxillofacial Surgery, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa, Japan.
| | - H Kitajima
- Department of Oral and Maxillofacial Surgery, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa, Japan
| | - S Omura
- Department of Oral and Maxillofacial Surgery/Orthodontics, Yokohama City University Medical Center, Yokohama, Kanagawa, Japan
| | - I Tohnai
- Department of Oral and Maxillofacial Surgery, Yokohama City University Graduate School of Medicine, Yokohama, Kanagawa, Japan
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Woo JM, Choi JY. Tonsillectomy as prevention and treatment of sleep-disordered breathing: a report of 23 cases. Maxillofac Plast Reconstr Surg 2016; 38:47. [PMID: 27995120 PMCID: PMC5122598 DOI: 10.1186/s40902-016-0092-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 10/14/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The paradigm of tonsillectomy has shifted from a treatment of recurrent throat infection to one of multi-discipline management modalities of sleep-disordered breathing (SDB). While tonsillectomy as a treatment for throat problems has been performed almost exclusively by otorhinolaryngologists, tonsillectomy as a part of the armamentarium for the multifactorial, multidisciplinary therapy of sleep-disordered breathing needs a new introduction to those involved in treating SDB patients. This study has its purpose in sharing a series of tonsillectomies performed at the Seoul National University Dental Hospital for the treatment and prevention of SDB in adult patients. METHODS Total of 78 patients underwent tonsillectomy at the Seoul National University Dental Hospital from 1996 to 2015, and 23 of them who were operated by a single surgeon (Prof. Jin-Young Choi) were included in the study. Through retrospective chart review, the purpose of tonsillectomy, concomitant procedures, grade of tonsillar hypertrophy, surgical outcome, and complications were evaluated. RESULTS Twenty-one patients diagnosed with SDB received multiple surgical procedures (uvulopalatal flap, uvulopalatopharyngoplasty, genioglossus advancement genioplasty, tongue base reduction, etc.) along with tonsillectomy. Two patients received mandibular setback orthognathic surgery with concomitant tonsillectomy in anticipation of postoperative airway compromise. All patients showed improvement in symptoms such as snoring and apneic events during sleep. CONCLUSIONS When only throat infections were considered, tonsillectomy was a procedure rather unfamiliar to oral and maxillofacial surgeons. With a shift of primary indication from recurrent throat infections to SDB and emerging technological and procedural breakthroughs, simpler and safer tonsillectomy has become a major tool in the multidisciplinary treatment modality for SDB.
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Affiliation(s)
- Jae-Man Woo
- Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital, 101 Daehakno, Jongno-Gu, Seoul, 110-768 Republic of Korea
| | - Jin-Young Choi
- Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital, 101 Daehakno, Jongno-Gu, Seoul, 110-768 Republic of Korea ; Department of Oral and Maxillofacial Surgery, School of Dentistry, Seoul National University, Seoul, Republic of Korea
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Karm MH, Chi SI, Kim J, Kim HJ, Seo KS, Bahk JH, Park CJ. Effects of airway evaluation parameters on the laryngeal view grade in mandibular prognathism and retrognathism patients. J Dent Anesth Pain Med 2016; 16:185-191. [PMID: 28884151 PMCID: PMC5586555 DOI: 10.17245/jdapm.2016.16.3.185] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 09/21/2016] [Accepted: 09/22/2016] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Failure to maintain a patent airway can result in brain damage or death. In patients with mandibular prognathism or retrognathism, intubation is generally thought to be difficult. We determined the degree of difficulty of airway management in patients with mandibular deformity using anatomic criteria to define and grade difficulty of endotracheal intubation with direct laryngoscopy. METHODS Measurements were performed on 133 patients with prognathism and 33 with retrognathism scheduled for corrective esthetic surgery. A case study was performed on 89 patients with a normal mandible as the control group. In all patients, mouth opening distance (MOD), mandibular depth (MD), mandibular length (ML), mouth opening angle (MOA), neck extension angle (EXT), neck flexion angle (FLX), thyromental distance (TMD), inter-notch distance (IND), thyromental area (TMA), Mallampati grade, and Cormack and Lehane grade were measured. RESULTS Cormack and Lehane grade I was observed in 84.2%, grade II in 15.0%, and grade III in 0.8% of mandibular prognathism cases; among retrognathism cases, 45.4% were grade I, 27.3% grade II, and 27.3% grade III; among controls, 65.2% were grade I, 26.9% were grade II, and 7.9% were grade III. MOD, MOA, ML, TMD, and TMA were greater in the prognathism group than in the control and retrognathism groups (P < 0.05). The measurements of ML were shorter in retrognathism than in the control and prognathism groups (P < 0.05). CONCLUSIONS Laryngoscopic intubation was easier in patients with prognathism than in those with normal mandibles. However, in retrognathism, the laryngeal view grade was poor and the ML was an important factor.
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Affiliation(s)
- Myong-Hwan Karm
- Department of Dental Anesthesiology, Seoul National University Dental Hospital, Seoul, Korea
| | - Seong In Chi
- Department of Dental Anesthesiology, Seoul National University Dental Hospital, Seoul, Korea
| | - Jimin Kim
- Department of Dental Anesthesiology, Seoul National University Dental Hospital, Seoul, Korea
| | - Hyun Jeong Kim
- Department of Dental Anesthesiology, Seoul National University Dental Hospital, Seoul, Korea
| | - Kwang-Suk Seo
- Department of Dental Anesthesiology, Seoul National University Dental Hospital, Seoul, Korea
| | - Jae-Hyon Bahk
- Department of Anesthesiology and Pain Medicine, Seoul National University, College of Medicine, Seoul, Korea
| | - Chang-Joo Park
- Division of Oral and Maxillofacial Surgery, Department of Dentistry, College of Medicine, Hanyang University, Seoul, Korea
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Are Hyoid Bone and Tongue the Risk Factors Contributing to Postoperative Relapse for Mandibular Prognathism? BIOMED RESEARCH INTERNATIONAL 2016; 2016:5284248. [PMID: 27042664 PMCID: PMC4793095 DOI: 10.1155/2016/5284248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 01/20/2016] [Accepted: 01/24/2016] [Indexed: 12/01/2022]
Abstract
Objective. The purpose of this study was to investigate postoperative stability and the correlation between hyoid, tongue, and mandible position following surgery for mandibular prognathism. Materials and Methods. Thirty-seven patients, treated for mandibular prognathism using intraoral vertical ramus osteotomy (IVRO), were evaluated cephalometrically. A set of four standardized lateral cephalograms were obtained from each subject preoperatively (T1), immediately postoperatively (T2), six weeks to three months postoperatively (T3), and more than one year postoperatively (T4). The Student t-tests, the Pearson correlation coefficient, and the multiple linear regression were used for statistical analysis. Results. Immediately after surgery, menton (Me) setback was 12.8 mm, hyoid (H) setback was 4.9 mm, and vallecula epiglottica (V) setback was 5.8 mm. The postoperative stability significantly correlated (r = −0.512, p < 0.01) with the amount of setback. The hyoid bone and tongue did not have significant effects on postoperative stability. Multiple linear regression model (R2 = 0.2658, p < 0.05) showed predictability: Horizontal Relapse Me (T4-T2) = −6.406 − 0.488Me (T2-T1) + 0.069H (T2-T1) − 0.0619V (T2-T1). Conclusion. Mandibular setback surgery may push the hyoid and tongue significantly backward, but this did not correlate with mandibular relapse. Postoperative stability significantly correlated with the amount of mandibular setback.
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Retrospective study of changes in pharyngeal airway space and position of hyoid bone after mandibular setback surgery by cephalometric analysis. Maxillofac Plast Reconstr Surg 2015; 37:38. [PMID: 26523276 PMCID: PMC4620125 DOI: 10.1186/s40902-015-0039-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 10/15/2015] [Indexed: 12/01/2022] Open
Abstract
Background The posterior movement of mandible was known as the main cause of the changes in the pharyngeal airway space (PAS) and the postoperative obstructive sleep apnea (OSA). The purpose of this study was to know the changes of PAS and position of hyoid bone. Methods Lateral cephalographies of 13 patients who had undergone sagittal split ramus osteotomy (SSRO) setback surgery were taken preoperatively (T1), postoperatively within 2 months (T2), and follow-up after 6 months or more (T3). On the basis of F-H plane, diameters of nasopharynx, oropharynx, and hypopharynx were measured. The movements of the soft palate, tongue, and hyoid bone were also measured. Results The amount of mandible setback was 7.5 ± 3.8 mm. In the measurements of PAS, there was a statistically significant decrease of 2.8 ± 2.5 mm in nasopharynx (P < 0.01), and 1.7 ± 2.4 mm in oropharynx (P < 0.01) were observed after surgery. The hypopharynx decreased 1.0 ± 2.1 mm after surgery and continuously decreased 1.0 ± 2.8 mm at follow-up. The changes in hyoid bone position showed the posterior movement only after surgery and posteroinferior movement at follow-up. Conclusions The PAS such as nasopharynx, oropharynx, and hypopharynx showed relatively high correlation with the amount of mandibular setback. The change of resistance in upper airway may be important for the prevention of OSA after mandibular setback surgery.
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Canellas JVDS, Barros HLM, Medeiros PJD, Ritto FG. Sleep-disordered breathing following mandibular setback: a systematic review of the literature. Sleep Breath 2015; 20:387-94. [PMID: 26467041 DOI: 10.1007/s11325-015-1274-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 09/29/2015] [Accepted: 10/05/2015] [Indexed: 12/22/2022]
Abstract
INTRODUCTION A mandibular setback reduces space in the pharyngeal airway, and it has been suggested that it might induce sleep-disordered breathing. OBJECTIVES An evidence-based literature review was conducted to identify the effect of mandibular setback on the respiratory function during sleep. METHODS The authors performed a systematic review of pertinent literature published up to 2014. A structured search of literature was performed, with predefined criteria. A survey of the PubMed, ScienceDirect, and Cochrane database was performed. A manual search of oral and maxillofacial surgery-related journals was accomplished. Potentially relevant studies then had their full-text publication reviewed. RESULTS A total of 1,780 publications were evaluated, through which nine papers (seven case series and two case-control studies) were selected for the final review. No evidence of sleep disorder after six months was related in 223 patients. In one study, two patients developed obstructive sleep apnea syndrome after surgery, and in another two studies, seven patients presented an increase of obstructive apneas/hypopneas events and oxygen desaturation index. Most of the patients analyzed were young and thin. CONCLUSION There was no evidence of postoperative sleep apnea syndrome after a mandibular setback surgery. However, one should always consider a potential reduction of the upper airway space during the treatment plan. Obese patients and those submitted to large amounts of mandibular setbacks present a higher chance to develop obstructive sleep apnea syndrome.
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Affiliation(s)
| | - Hugo Leonardo Mendes Barros
- Rio de Janeiro State University, Rua Boulevard 28 de Setembro, 157 Vila Isabel, Rio de Janeiro, RJ, 20551-030, Brazil
| | | | - Fabio Gamboa Ritto
- Rio de Janeiro State University, Rua Boulevard 28 de Setembro, 157 Vila Isabel, Rio de Janeiro, RJ, 20551-030, Brazil
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Kim HS, Kim GT, Kim S, Lee JW, Kim EC, Kwon YD. Three-dimensional evaluation of the pharyngeal airway using cone-beam computed tomography following bimaxillary orthognathic surgery in skeletal class III patients. Clin Oral Investig 2015; 20:915-22. [DOI: 10.1007/s00784-015-1575-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Accepted: 08/18/2015] [Indexed: 11/30/2022]
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Al-Moraissi E, Al-Magaleh S, Iskandar R, Al-hendi E. Impact on the pharyngeal airway space of different orthognathic procedures for the prognathic mandible. Int J Oral Maxillofac Surg 2015; 44:1110-8. [DOI: 10.1016/j.ijom.2015.05.006] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 04/21/2015] [Accepted: 05/06/2015] [Indexed: 11/30/2022]
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Santagata M, Tozzi U, Lamart E, Tartaro G. Effect of Orthognathic Surgery on the Posterior Airway Space in Patients Affected by Skeletal Class III Malocclusion. J Maxillofac Oral Surg 2015; 14:682-6. [PMID: 26225062 PMCID: PMC4510090 DOI: 10.1007/s12663-014-0687-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 08/18/2014] [Indexed: 11/29/2022] Open
Abstract
INTRODUCTION Dentofacial deformity refers to deviations from normal facial proportions and dental relationships that are severe enough to be handicapping. These anomalies involve many aspects of patient's life and are sometimes also associated with a reduction of pharyngeal air space. Through orthognathic surgery it is possible to treat dentofacial deformities: this kind of surgery has several effects on skeletal structures and it has changes, as it is demonstrated by many studies, also on the upper airways. The orthognathic surgeries commonly used to correct this deformity are the mandibular setback and the maxillary advancement procedures. This study aims to evaluate the effects of maxillary and mandibular surgery on pharyngeal airway dimensions in skeletal class III malocclusions. MATERIALS AND METHODS This study considers 76 patients, treated between 2007 and 2013 by maxillary advancement (11 patients), maxillary advancement and mandibular setback (39 patients), maxillary advancement, mandibular setback and genioplasty reduction (26 patients). Cranial latero-lateral radiography was used to compare oropharyngeal airway morphologies before and 1 year after surgery. CONCLUSION The surgeon should consider bimaxillary surgery rather than mandibular setback surgery to correct a class III deformity to prevent the development of obstructive sleep apnea syndrome; in fact, bimaxillary surgery might have less effect on reduction of the pharyngeal airway than mandibular setback surgery only.
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Affiliation(s)
- Mario Santagata
- />Multidisciplinary Department of Medical and Dental Specialties, Oral and Maxillofacial Surgery Unit, AOU–SUN (Second University of Naples), Naples, Italy
- />Piazza Fuori Sant’Anna, 17, 81031 Aversa, Italy
| | - Umberto Tozzi
- />Multidisciplinary Department of Medical and Dental Specialties, Oral and Maxillofacial Surgery Unit, AOU–SUN (Second University of Naples), Naples, Italy
| | - Ettore Lamart
- />Multidisciplinary Department of Medical and Dental Specialties, Oral and Maxillofacial Surgery Unit, AOU–SUN (Second University of Naples), Naples, Italy
| | - Gianpaolo Tartaro
- />Multidisciplinary Department of Medical and Dental Specialties, Oral and Maxillofacial Surgery Unit, AOU–SUN (Second University of Naples), Naples, Italy
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Hirata K, Tanikawa C, Aikawa T, Ishihama K, Kogo M, Iida S, Yamashiro T. Asymmetric Anterior Distraction for Transversely Distorted Maxilla and Midfacial Anteroposterior Deficiency in a Patient With Cleft Lip/Palate: Two-Stage Surgical Approach. Cleft Palate Craniofac J 2015; 53:491-8. [PMID: 26237186 DOI: 10.1597/14-322] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present report describes a male patient with a unilateral cleft lip and palate who presented with midfacial anteroposterior and transverse deficiency. Correction involved a two-stage surgical-orthodontic approach: asymmetric anterior distraction of the segmented maxilla followed by two-jaw surgery (LeFort I and bilateral sagittal splitting ramus osteotomies). The present case demonstrates that the asymmetric elongation of the maxilla with anterior distraction is an effective way to correct a transversely distorted alveolar form and midfacial anteroposterior deficiency. Furthermore, successful tooth movement was demonstrated in the new bone created by distraction.
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Almuzian M, Almukhtar A, Ju X, Al-Hiyali A, Benington P, Ayoub A. Effects of Le Fort I Osteotomy on the Nasopharyngeal Airway-6-Month Follow-Up. J Oral Maxillofac Surg 2015; 74:380-91. [PMID: 26188102 DOI: 10.1016/j.joms.2015.06.172] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Revised: 06/25/2015] [Accepted: 06/26/2015] [Indexed: 11/17/2022]
Abstract
PURPOSE The literature discussing the impact of a single Le Fort I osteotomy on nasopharyngeal airways is limited. This study assessed the volumetric changes in the nasopharyngeal airway after a single Le Fort I osteotomy and explored the correlation between these changes and 3-dimensional surgical movements of the upper jaw. MATERIALS AND METHODS This retrospective study was conducted in 40 patients who had undergone a single Le Fort I (maxillary advancement with or without impaction) to correct Class III malocclusion with maxillary hypoplasia. Preoperative (T1) and 6-month postoperative (T2) cone-beam computed tomographic (CBCT) scans of these patients were used for analysis. Maxillary surgical movements and volumetric changes in the nasopharyngeal airway were measured. The reproducibility of the measurements was evaluated using paired t tests and intraclass correlation coefficients. The Wilcoxon test and Pearson correlation coefficient were applied to evaluate the volumetric changes in the nasopharyngeal airway space and assess the correlations of these changes to the maxillary surgical movements. RESULTS Six patients were excluded from the study owing to major differences (>5°) in their head and neck posture between the T1 and T2 CBCT scans. The errors of the repeated measurements were insignificant (P > .05), with a high level of agreement (r = 0.99; P < .05) between the repeated digitization of the landmarks. There was a statistically significant impact of a Le Fort I osteotomy on the right maxillary sinus (decreased by 17.8%) and the lower retropalatal space (expanded by 17.3%; P < .05). The correlation between the change in airway volume and the magnitude of surgical maxillary movements was moderate (r = .4). Similarly, there was a moderate correlation between changes in the upper nasopharynx and those in the hypopharynx. CONCLUSION The single Le Fort I osteotomy was found to increase the retroglossal airway volume. This could be important for the treatment of obstructive sleep apnea in patients with maxillary deficiency. A long-term follow-up assessment of a larger sample with a functional assessment of airway would be beneficial to confirm these findings.
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Affiliation(s)
- Mohammed Almuzian
- Honorary Specialist Registrar, Glasgow University, MVLS College, Glasgow Dental Hospital & School, Glasgow, UK.
| | - Anas Almukhtar
- Postgraduate Student, Glasgow University, MVLS College, Glasgow Dental Hospital & School, Glasgow, UK
| | - Xiangyang Ju
- Medical Devices Unit, NHS Greater Glasgow and Clyde, Glasgow, UK
| | - Ali Al-Hiyali
- Postgraduate Student, Glasgow University, MVLS College, Glasgow Dental Hospital & School, Glasgow, UK
| | - Philip Benington
- Consultant Orthodontist, Glasgow Dental Hospital & School, Glasgow, UK
| | - Ashraf Ayoub
- Professor, Department of Oral and Maxillofacial Surgery, Glasgow University, MVLS College, Glasgow Dental Hospital & School, Glasgow, UK
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Jeon JY, Kim TS, Kim SY, Park CJ, Hwang KG. Does the Pharyngeal Airway Recover After Sagittal Split Ramus Osteotomy for Mandibular Prognathism? J Oral Maxillofac Surg 2015; 74:162-9. [PMID: 26071362 DOI: 10.1016/j.joms.2015.05.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Revised: 05/13/2015] [Accepted: 05/19/2015] [Indexed: 12/17/2022]
Abstract
PURPOSE Mandibular setback surgery can adversely affect the pharyngeal airway. The aim of this study was to investigate changes of the pharyngeal airway at specific intervals during a 12-month period after bilateral sagittal split ramus osteotomy (BSSO) for correction of mandibular prognathism. MATERIALS AND METHODS This retrospective cohort study included patients with mandibular prognathism who underwent BSSO. The pharyngeal airway was measured at 3 different levels on lateral cephalograms: the uvula tip, the most inferior-anterior point on the body of the second cervical vertebra (low-C II), and a midanterior point on the body of the third cervical vertebra (mid-C III). The pharyngeal airway was measured preoperatively, immediately postoperatively, and 1, 3, 6, and 12 months postoperatively. The measurements at each level were compared. Multivariable analysis of variance was used to measure the changes in pharyngeal airway space over time. RESULTS The study sample was composed of 30 patients (14 men and 16 women) who were diagnosed with mandibular prognathism. The pharyngeal airway at the uvular tip level was significantly reduced by 39% (P < .001) after surgery and was significantly improved by 26% (P < .01) from baseline at 1 month postoperatively. The pharyngeal airway at the low-C II level was significantly reduced by 27% (P < .001) after surgery and was significantly improved by 24% (P < .01) from baseline at 1 month postoperatively. The pharyngeal airway at the mid-C III level was significantly reduced by 23% (P < .001) after surgery and was improved by only 13% from baseline at 1 month postoperatively. Additional statistical changes were not noted on 3 and 6 months postoperative radiographs at all levels. The pharyngeal airway was decreased by 16, 19, and 8% from baseline at 12 months postoperatively, respectively. The upper airway length was significantly increased immediately after surgery (P < .001), but was incompletely recovered at 12 months postoperatively. CONCLUSION The outcomes of this study indicate that the pharyngeal airway gradually recovers over time. An immediate postoperative reduction in pharyngeal airway space can induce or exacerbate obstructive sleep apnea symptoms; thus, any pre-existing symptoms should be screened and considered for surgical treatment planning.
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Affiliation(s)
- Jae-Yun Jeon
- Clinical Lecturer, Department of Dentistry/Oral and Maxillofacial Surgery, College of Medicine, Hanyang University, Seoul, Korea
| | - Tae-Sun Kim
- PhD Candidate, Department of Dentistry/Oral and Maxillofacial Surgery, College of Medicine, Hanyang University, Seoul; Private Practice, Gimpo, Gyeonggi, Korea
| | - Sang Yoon Kim
- Former Chief Resident, Department of Oral and Maxillofacial Surgery, Massachusetts General Hospital, Harvard Medical School, Boston; Private Practice, Vienna, VA
| | - Chang-Joo Park
- Associate Professor, Department of Dentistry/Oral and Maxillofacial Surgery, College of Medicine, Hanyang University, Seoul, Korea
| | - Kyung-Gyun Hwang
- Professor, Department of Dentistry/Oral and Maxillofacial Surgery, College of Medicine, Hanyang University, Seoul, Korea.
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Correlation between the Pharyngeal Airway Space and Head Posture after Surgery for Mandibular Prognathism. BIOMED RESEARCH INTERNATIONAL 2015; 2015:251021. [PMID: 25977919 PMCID: PMC4421098 DOI: 10.1155/2015/251021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2015] [Revised: 03/17/2015] [Accepted: 04/06/2015] [Indexed: 11/30/2022]
Abstract
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. Paired t-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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Gokce SM, Gorgulu S, Gokce HS, Bengi AO, Karacayli U, Ors F. Evaluation of pharyngeal airway space changes after bimaxillary orthognathic surgery with a 3-dimensional simulation and modeling program. Am J Orthod Dentofacial Orthop 2015; 146:477-92. [PMID: 25263151 DOI: 10.1016/j.ajodo.2014.06.017] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2013] [Revised: 06/01/2014] [Accepted: 06/01/2014] [Indexed: 11/17/2022]
Abstract
INTRODUCTION The aims of this study were to use 3-dimensional simulation and modeling programs to evaluate the effects of bimaxillary orthognathic surgical correction of Class III malocclusions on pharyngeal airway space volume, and to compare them with the changes in obstructive sleep apnea measurements from polysomnography. METHODS Twenty-five male patients (mean age, 21.6 years) with mandibular prognathism were treated with bilateral sagittal split osteotomy and LeFort I advancement. Polysomnography and computed tomography were performed before surgery and 1.4 ± 0.2 years after surgery. All computed tomography data were transferred to a computer, and the pharyngeal airway space was segmented using SimPlant OMS (Materialise Medical, Leuven, Belgium) programs. The pretreatment and posttreatment pharyngeal airway space determinants in volumetric, linear distance, and cross-sectional measurements, and polysomnography changes were compared with the paired samples t test. Pearson correlation was used to analyze the association between the computed tomography and polysomnography measurements. RESULTS The results indicated that setback procedures produce anteroposterior narrowing of the pharyngeal airway space at the oropharyngeal and hypopharyngeal levels and the middle and inferior pharyngeal volumes (P <0.05). In contrast, advancement of the maxilla causes widening of the airway in the nasopharyngeal and retropalatal dimensions and increases the superior pharyngeal volume (P <0.05). Distinctively, bimaxillary orthognathic surgery induces significant increases in the total airway volume and the transverse dimensions of all airway areas (P <0.05). Significant correlations were found between the measurements on the computed tomography scans and crucial polysomnography parameters. CONCLUSIONS Bimaxillary orthognathic surgery for correction of Class III malocclusion caused an increase of the total airway volume and improvement of polysomnography parameters. A proposed treatment plan can be modified according to the risk of potential airway compromise or even to improve it with 3-dimensional imaging techniques and polysomnography.
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Affiliation(s)
- Sila Mermut Gokce
- Associate professor, Department of Orthodontics, Dental Sciences Center, Gulhane Military Medical Academy, Etlik, Ankara, Turkey.
| | - Serkan Gorgulu
- Associate professor, Department of Orthodontics, Dental Sciences Center, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - Hasan Suat Gokce
- Associate professor, Medical Design and Manufacturing Center, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - Ali Osman Bengi
- Professor and chairman of Dental Sciences Center, Department of Orthodontics, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - Umit Karacayli
- Associate professor, Department of Orthodontics, Dental Sciences Center, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
| | - Fatih Ors
- Associate professor, Department of Radiology, Gulhane Military Medical Academy, Etlik, Ankara, Turkey
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Hatab NA, Konstantinović VS, Mudrak JKH. Pharyngeal airway changes after mono- and bimaxillary surgery in skeletal class III patients: Cone-beam computed tomography evaluation. J Craniomaxillofac Surg 2015; 43:491-6. [PMID: 25794643 DOI: 10.1016/j.jcms.2015.02.007] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Revised: 12/19/2014] [Accepted: 02/10/2015] [Indexed: 11/25/2022] Open
Abstract
The aim of this study was to evaluate the two-dimensional (2D) and three-dimensional (3D) changes in the pharyngeal airway space (PAS) in 20 class III patients who underwent mono- or bimaxillary surgery using cone-beam computed tomography (CBCT). CBCT examination was obtained before surgery (T1) and at least 3 months after surgery (T2). The pharyngeal airway of each patient was studied at three levels: the level of the posterior nasal spine, the level of the most inferior point of the soft palate, and the level of the top of the epiglottis. At each of these levels, the anteroposterior and lateral dimension as well as cross-sectional area were measured. The volume of the whole PAS and volume between each cross section were also measured. The area and anteroposterior dimensions at the level of the most inferior point of the soft palate significantly decreased in patients who underwent monomaxillary surgery. The volume of the PAS decreased in both groups, but decreased significantly only in the monomaxillary group. The upper volume decreased in the mono- and increased in the bimaxillary group. The lower volume significantly decreased in the monomaxillary group. However, results showed that PAS decreased more after mono-than after bimaxillary surgery.
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Affiliation(s)
- N A Hatab
- Clinic of Maxillofacial Surgery, School of Dental Medicine, University of Belgrade, Dr Subotića 4, 11000 Belgrade, Serbia.
| | - V S Konstantinović
- Clinic of Maxillofacial Surgery, School of Dental Medicine, University of Belgrade, Dr Subotića 4, 11000 Belgrade, Serbia
| | - J K H Mudrak
- Private Dental Clinic, Am Stetenrain 8, 36251 Ludwigsau, Germany
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