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Gao H, Bi D, Al-Watary MQH, Song L, Sun X, Zhao Q, Li J. Morphological Changes of the Mandibular Angle After Orthognathic Surgery with Class III Deformity in East Asia. Aesthetic Plast Surg 2024; 48:816-826. [PMID: 37758853 DOI: 10.1007/s00266-023-03658-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 09/06/2023] [Indexed: 09/29/2023]
Abstract
The aims of this study were to analyze the morphological changes of the mandibular angle after orthognathic surgery for mandibular setback and investigate related factors. This retrospective study included patients from January 2017 to December 2021 diagnosed with skeletal class III deformity who underwent BSSRO (Group I) or bimaxillary surgery (Group II). Preoperative (T0), within 1 month postoperatively (T1), and 6 months postoperatively (T2) CT scans were collected from 61 patients to three-dimensionally analyze the proximal segment displacement, the linear and angular changes of the mandibular angle. The gonion points moved posteriorly and laterally (P < 0.001), while the inferior movement was not significant (P = 1.000, P = 0.274). The intergonial width increased by 3.32 ± 1.87 mm and 2.34 ± 1.77 mm as revealed by T2 CTs, respectively, in Group I and Group II. Mandibular angle decreased in both groups and by 1.41 ± 2.95° in Group I and 1.37 ± 3.41° in Group II. The increase in intergonial width between T1 and T0 was negatively correlated with the preoperative mandibular angle (P = 0.003) and positively correlated with the transverse outward movement of the proximal segment (P < 0.001). After surgery, the intergonial width increased and the inferior and posterior border of the proximal segment flared outward. The changes in intergonial width and mandibular angle were mainly related to the rotation of the proximal segment, which has a certain impact on the aesthetics of the lower face. Therefore, controlling the position of the proximal segment is of vital importance to lessen the changes in the mandibular angle area.Level of Evidence III. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Affiliation(s)
- Heyou Gao
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases and Department of Orthognathic and TMJ Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - DanDan Bi
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases and Department of Orthognathic and TMJ Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Mohammed Qasem Hezam Al-Watary
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases and Department of Orthognathic and TMJ Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Libin Song
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases and Department of Orthognathic and TMJ Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xiaoshuang Sun
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases and Department of Orthognathic and TMJ Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Qing Zhao
- State Key Laboratory of Oral Diseases and National Clinical Research Center for Oral Diseases and Department of Orthognathic and TMJ Surgery, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Jihua Li
- West China College of Stomatology Sichuan University, Chengdu, 610041, China.
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Liao YF, Chen YF, Chang CS, Lu TC, Chen YA, Yao CF, Chen PKT, Chen YR. Surgery-First Orthognathic Approach for Correction of Dentofacial Deformity in Unilateral Cleft Lip and Palate. Plast Reconstr Surg 2024; 153:173-183. [PMID: 36946892 DOI: 10.1097/prs.0000000000010451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
BACKGROUND Although several studies have reported the advantages of the surgery-first approach for orthognathic correction of class III deformity, there is no report of the success of this approach for patients with cleft lip and palate. Therefore, the purpose of this study was to evaluate the stability and outcome of bimaxillary surgery for cleft-related dentofacial deformity using a surgery-first approach. METHODS Forty-one patients with unilateral cleft lip and palate who consecutively underwent Le Fort I and bilateral sagittal split osteotomies for skeletal class III deformity were included. Cone-beam computed tomographic scans before surgery, 1 week after surgery, and after orthodontic treatment were used to measure the surgical and postsurgical changes in jaw position by landmarks, and outcomes of jaw protrusion and relation, incisor angle and occlusion, and menton deviation after treatment. Self-report questionnaires regarding satisfaction with overall appearance of the face and seven facial regions were administered after treatment. RESULTS A clinically insignificant relapse was found in the maxilla (<1 mm) and mandible (<2 mm). There was a significant improvement in the jaw protrusion and relation, incisor angle and occlusion, and menton deviation. Responses from the self-report questionnaires completed after treatment indicated that patient satisfaction was high. CONCLUSION These findings demonstrate surgical-orthodontic treatment with a surgery-first approach can successfully improve cleft-related dentofacial deformity in patients with unilateral cleft lip and palate. CLINICAL QUESTION/LEVEL OF EVIDENCE Therapeutic, IV.
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Affiliation(s)
- Yu-Fang Liao
- From the Graduate Institute of Dental and Craniofacial Science, College of Medicine, Chang Gung University
- Department of Craniofacial Orthodontics
- Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan
- Craniofacial Research Center
| | - Yun-Fang Chen
- Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan
- Craniofacial Research Center
- Department of Craniofacial Orthodontics, Chang Gung Memorial Hospital, Taipei
| | - Chun-Shin Chang
- Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan
- Craniofacial Research Center
- Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, Linkou
| | - Ting-Chen Lu
- Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan
- Craniofacial Research Center
- Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, Linkou
| | - Ying-An Chen
- Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan
- Craniofacial Research Center
- Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, Linkou
| | - Chuan-Fong Yao
- Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan
- Craniofacial Research Center
- Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, Linkou
| | | | - Yu-Ray Chen
- From the Graduate Institute of Dental and Craniofacial Science, College of Medicine, Chang Gung University
- Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan
- Craniofacial Research Center
- Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital, Linkou
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Changes and Remodeling of Intersegmental Interferences following Bilateral Sagittal Split Ramus Osteotomy in Patients with Mandibular Prognathism. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12041892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Purpose: This study aimed to measure the amount of change in the mandibular angle, intergonial width, and ramus angulation due to intersegmental interference and changes in condyle position after mandibular bilateral sagittal split ramus osteotomy (BSSRO) in patients with mandibular prognathism and to evaluate the correlation between them. Materials and Methods: A total of 32 patients who underwent mandibular setback using the BSSRO of the mandible to manage skeletal prognathism during the years 2018 to 2020 at the Department of Oral and Maxillofacial Surgery, Pusan National University were followed both clinically and with cone beam computed tomography (CBCT) for at least one year. Those who were also treated with genioplasty or other orthognathic surgery were excluded from the study. The mandibular angle (gonial angle: Ar–Go–Me), intergonial width (Go–Go), and total angle (sum of left and right proximal segmental angle) were recorded. Changes in the ramus were compared and analyzed before surgery (T1), immediately after surgery (T2), and one year following surgery (T3). Results: The mandibular angle increased by an average of 0.14 degrees immediately after surgery (T2–T1) and increased by 0.97 degrees at 12 months postoperatively (T3–T2). No correlation was observed with the amount of change in each group relative to the amount of mandibular setback. The mandibular width decreased by 0.01 mm on average immediately after surgery (T2–T1), and by 4.2 mm on average at 12 months after surgery (T3–T2). The angle of the mesial fragment of the mandible increased by 1.04 degrees immediately after surgery (T2–T1), compared to the preoperative state. It decreased by 0.86 degrees at 12 months postoperatively (T3–T2). Conclusion: The increase in the mandibular angle from immediately after surgery to 12 months after BSSRO reflects the counterclockwise rotational tendency to prevent opening restriction when intentionally selecting the condylar position. The decrease in the intergonial width immediately after surgery is thought to be due to the effect of internal trimming to minimize the bone interference between the outer surface of the distal bone fragment and the inner surface of the mesial fragment, and the decrease 1 year after surgery can be considered to be due to bone remodeling. Interosseous interference during mandibular setback osteotomy does not necessarily cause an increase in the width of the mandibular angle after surgery.
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Chen CM, Ko ECC, Cheng JH, Tseng YC. Correlation between changes in the gonial area and postoperative stability in the treatment of mandibular prognathism. JOURNAL OF STOMATOLOGY, ORAL AND MAXILLOFACIAL SURGERY 2019; 120:414-418. [PMID: 30664955 DOI: 10.1016/j.jormas.2018.12.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 12/07/2018] [Accepted: 12/20/2018] [Indexed: 10/27/2022]
Abstract
INTRODUCTION The present study was to investigate the relationship between the post-operative area of the gonial region (lateral and frontal) and post-operative relapse. MATERIAL AND METHODS Thirty-seven patients, treated for mandibular prognathism were followed with serial lateral cephalograms [pre-operatively (T1), immediately after surgery (T2), and at least 2 years post-operatively (T3)]. The surgical changes (T21), post-operative stability (T32) and 2-year surgical change (T31) were evaluated by the Student's t-test. Pearson's correlation coefficient analysis was used to determine the correlations between the cephalometric parameters. Multiple linear regression analysis was used to assess the association between the risk factors and post-operative relapse. RESULTS The immediate post-operative changes (T21), mean setback of the Me was 12.3 mm and the frontal gonial area (T2) was increased by 138.7 mm2. The final post-operative changes (T31), lateral gonial area was significantly reduced by 190.5 mm2. CONCLUSION Relapse was significantly correlated with the amount of setback. However, changes in the area of the gonial region (lateral and frontal) showed weak correlation with relapse. Multiple regression analysis also showed poor predictability of relapse. In conclusion, the results of this study showed that significant changes in the area of the gonial region (lateral and frontal) did not affect the maintenance of post-operative stability.
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Affiliation(s)
- C-M 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
| | - E C-C Ko
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Oral and Maxillofacial Surgery, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - J-H Cheng
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Y-C Tseng
- School of Dentistry, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan; Department of Orthodontics, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan.
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Choi TH, Kim SH, Yun PY, Kim YK, Lee NK. Factors Related to Relapse After Mandibular Setback Surgery With Minimal Presurgical Orthodontics. J Oral Maxillofac Surg 2019; 77:1072.e1-1072.e9. [PMID: 30707985 DOI: 10.1016/j.joms.2018.12.030] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2018] [Revised: 12/08/2018] [Accepted: 12/25/2018] [Indexed: 11/19/2022]
Abstract
PURPOSE The aims of this study were to compare the presurgical conditions, surgical changes, and postsurgical changes in patients with skeletal Class III malocclusion with different degrees of horizontal relapse after mandibular setback surgery (MS) with minimal presurgical orthodontics (MPO) and to identify the factors contributing to this relapse. MATERIALS AND METHODS For this retrospective study, 33 consecutive patients who underwent MS-MPO were selected. Lateral cephalograms were taken preoperatively (T0), 1 month after surgery (T1), and at orthodontic debonding (T2). Patients were divided into low relapse (LR; n = 18; relapse, <1 mm) and high relapse (HR; n = 15; relapse, >2 mm) groups based on the cephalometric distance of mandibular horizontal relapse. Paired t test, independent t test, and Pearson correlation analysis were used to evaluate surgical (T0 to T1) and postsurgical (T1 to T2) changes in the skeletodental variables and to explore the relation between surgical changes and horizontal relapse. RESULTS Compared with the LR group, the HR group exhibited more upward movement with counterclockwise rotation of the mandible from T1 to T2. The HR group presented at T0 with a more prognathic mandible, greater vertical facial height, and a positive overbite. In addition, the HR group presented more posterior movement with clockwise rotation of the mandible, increased overjet, and decreased overbite from T0 to T1. Horizontal relapse of the mandible was positively correlated with the amount of setback and clockwise rotation of the mandible and the change in overjet and was negatively correlated with the change in overbite. CONCLUSIONS Mandibular instability was related to the extent of setback and clockwise rotation of the mandible, decreased overbite, and increased overjet during MS-MPO.
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Affiliation(s)
- Tae-Hyun Choi
- Clinical Assistant Professor, Department of Orthodontics, Seoul National University Bundang Hospital, Seongnam, Korea
| | - So-Hyun Kim
- Resident, Department of Orthodontics, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Pil-Young Yun
- Professor and Chair, Department of Oral and Maxillofacial Surgery, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Young-Kyun Kim
- Professor, Department of Oral and Maxillofacial Surgery, Seoul National University Bundang Hospital, Seongnam, Korea
| | - Nam-Ki Lee
- Professor, Department of Orthodontics, Seoul National University Bundang Hospital, Seongnam, Korea.
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Cottrell DA, Farrell B, Ferrer-Nuin L, Ratner S. Surgical Correction of Maxillofacial Skeletal Deformities. J Oral Maxillofac Surg 2017; 75:e94-e125. [DOI: 10.1016/j.joms.2017.04.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Relationship between Frontal Gap and Postoperative Stability in the Treatment of Mandibular Prognathism. BIOMED RESEARCH INTERNATIONAL 2016; 2016:7046361. [PMID: 27774457 PMCID: PMC5059647 DOI: 10.1155/2016/7046361] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Revised: 08/28/2016] [Accepted: 09/08/2016] [Indexed: 11/17/2022]
Abstract
Objectives. To investigate the correlation between frontal gaps and skeletal stability after intraoral vertical ramus osteotomy (IVRO) for correction of mandibular prognathism. Materials and Methods. Thirty-three patients with frontal gaps after IVRO-based mandibular prognathism correction were included. Three lateral and frontal cephalometric radiographs were obtained: preoperatively (T1), immediately postoperatively (T2), and 2 years postoperatively (T3). Two linear measurements (menton [Me] and frontal gap) were compared from T1 to T3 (T21: immediate surgical changes; T32: postoperative stability; T31: 2-year surgical change). Data were analyzed using Pearson's correlation coefficient and multiple linear regression. Results. The T21 mean surgical horizontal change in the Me position was 12.4 ± 4.23 mm. Vertically, the mean downward Me movement was 0.6 ± 1.73 mm. The mean frontal gaps were 4.7 ± 2.68 mm and 4 ± 2.48 mm in the right and left gonial regions, respectively. Postoperative stability (T32) significantly correlated with the amount of setback. Frontal gaps did not have a significant effect on postoperative stability. However, multiple regression model (R2 = 0.341, P = 0.017) showed value predictability, especially in the amount of setback. Conclusion. Frontal gaps occur after IVRO but have no significant effect on long-term postoperative skeletal stability. The primary risk factor for postoperative relapse remains the amount of mandibular setback.
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Tabrizi R, Pakshir H, Behnia H, Akhlaghi S, Shahsavari N. Does mandibular osteotomy affect gonial angle in patients with class III deformity? Vertical ramus osteotomy versus sagittal split osteotomy. Int J Oral Maxillofac Surg 2016; 45:992-6. [PMID: 27012604 DOI: 10.1016/j.ijom.2016.02.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 11/18/2015] [Accepted: 02/25/2016] [Indexed: 11/18/2022]
Abstract
The mandibular angle represents an important part of facial aesthetics. Mandibular osteotomy can affect the gonial angle. The aim of this study was to compare the effects of sagittal split osteotomy (SSO) and intraoral vertical ramus osteotomy (IVRO) on the gonial angle. This retrospective cohort study assessed subjects with mandibular prognathism who underwent SSO (group 1) or IVRO (group 2). Lateral cephalograms obtained before and 1 year after the osteotomies were analyzed. In this study, age, sex, the change in occlusal plane (OP) and mandibular plane (MP) angles, and the amount of mandibular setback were considered as variable factors, while the type of surgery (SSO or IVRO) was considered the predictive factor. Fifty-six subjects were studied: 26 in group 1 and 30 in group 2. The changes in MP angle and OP angle were not significantly different between the groups (P>0.05). The change in gonial angle was 6.07±4.46° in group 1 and 7.33±5.73° in group 2; assessment of the data did not demonstrate a significant difference between the two groups studied (P=0.53). Mandibular osteotomy (SSO or IVRO) may change the gonial angle, but a significant difference between SSO and IVRO was not detected.
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Affiliation(s)
- R Tabrizi
- School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran.
| | - H Pakshir
- School of Dentistry, Shiraz University of Medical Sciences, Shiraz, Iran
| | - H Behnia
- School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - S Akhlaghi
- International Branch, Shiraz University of Medical Sciences, Shiraz, Iran
| | - N Shahsavari
- School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Lee J, Kim YI, Hwang DS, Kim KB, Park SB. Effect of occlusal vertical dimension changes on postsurgical skeletal changes in a surgery-first approach for skeletal Class III deformities. Am J Orthod Dentofacial Orthop 2014; 146:612-9. [PMID: 25439212 DOI: 10.1016/j.ajodo.2014.07.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2014] [Revised: 07/01/2014] [Accepted: 07/01/2014] [Indexed: 10/24/2022]
Abstract
INTRODUCTION The purposes of this study were to investigate the relationship between occlusal vertical dimension (VD) changes and postsurgical skeletal changes in the surgery-first approach and to derive regression models for the final mandibular setback at B-point. METHODS This retrospective study included 40 patients (16 men, 24 women; ages, 22.6 ± 4.0 years) who had undergone a bimaxillary surgery-first approach. Using cephalograms generated from cone-beam computed tomography representing the presurgical, postsurgical, and posttreatment stages, skeletal landmarks in the maxilla and mandible were investigated to derive multivariate linear regression-based prediction models. Additionally, a patient classification based on the VD was established and verified to generate regression models for the classified groups. RESULTS For the nonincreased VD group, the surgical setback of B-point was its predictor for the final mandibular setback (R(2) at 92%). Meanwhile, the final mandibular setback of the increased VD group was predicted according to the surgical upward movement of pogonion, the postsurgical horizontal position of A-point, and the postsurgical vertical position of the coronoid process (R(2) at 94%). CONCLUSIONS The results of this study support the clinical observation that the more increased the vertical occlusal dimension after surgery, the less predictable the position of B-point at the posttreatment stage.
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Affiliation(s)
- Jihyun Lee
- Postgraduate student, Department of Orthodontics, Pusan National University Hospital, Busan, South Korea
| | - Yong-Il Kim
- Assistant professor, Department of Orthodontics, Dental Research Institute, Pusan National University Dental Hospital, Busan, South Korea.
| | - Dae-Seok Hwang
- Assistant professor, Department of Oral & Maxillofacial Surgery, Pusan National University Hospital, Busan, South Korea
| | - Ki Beom Kim
- Associate professor, Department of Orthodontics, Center for Advanced Dental Education, St Louis University, St Louis, Mo
| | - Soo-Byung Park
- Professor, Department of Orthodontics, Pusan National University Dental Hospital, Yangsan, South Korea
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Consideration of effect of the amount of mandibular setback on the submental region in the planning of orthodontic-orthognathic treatment. Br J Oral Maxillofac Surg 2014; 52:334-9. [PMID: 24593896 DOI: 10.1016/j.bjoms.2014.01.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 01/20/2014] [Indexed: 11/23/2022]
Abstract
Aesthetic outcome has gained in importance in the treatment of patients with orthognathic problems. Historically, Class III malocclusions have historically been treated by isolated mandibular setback and maxillary advancement, whereas bimaxillary procedures have recently become the more common option. Functional outcome and stability have been discussed previously. The aim of this observational study was to evaluate the effect of mandibular setback (BSSO) on the cervical region. We studied 38 Class III patients (20 women and 18 men, mean (SD) age 25 (0.8) years) who we identified from our clinical records and who were treated between 1 January 2002 and 30 December 2012 with mandibular setback procedures and followed up for 6 months. To study the effect of the amount of mandibular setback on the aesthetic outcome we have distinguished between patients with less than 5mm setback and those with 5mm or more. In patients whose mandibular setback was less than 5mm there was no significant change in cervical length. However, it decreased significantly in patients in whom the movement was 5mm or more. Postoperatively the lip-chin-throat angle (p=0.02), the length of the lower lip (p=0.002), and the length of the upper lip (p=0.003) from the aesthetic line also differed significantly between the 2 groups. Our observations strongly suggest that all these relations should be considered when treatment is being planned to avoid an unpleasant aesthetic impact on the chin region.
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