Feasibility of preoperative planning using anatomical facsimile models for mandibular reconstruction

A hierarchy of stability exists among the types of surgical movements that are possible with orthognathic surgery. This report updates the hierarchy, focusing on comparison of the stability of procedures when rigid fixation is used. Two procedures not previously placed in the hierarchy now are included: correction of asymmetry is stable with rigid fixation and repositioning of the chin also is very stable. During the first post-surgical year, surgical movements in patients treated for Class II/long face problems tend to be more stable than those treated for Class III problems. Clinically relevant changes (more than 2 mm) occur in a surprisingly large percentage of orthognathic surgery patients from one to five years post-treatment, after surgical healing is complete. During the first post-surgical year, patients treated for Class II/long face problems are more stable than those treated for Class III problems; from one to five years post-treatment, some patients in both groups experience skeletal change, but the Class III patients then are more stable than the Class II/long face patients. Fewer patients exhibit long-term changes in the dental occlusion than skeletal changes, because the dentition usually adapts to the skeletal change.     

基于 CBCT 影像的新图像配准技术在颞下颌关节疾病诊疗中的运用

目的 基于CBCT影像的新图像配准技术在颞下颌关节疾病诊疗的流程，并对其可靠性进行评 价。方法 选取2022年1月-2023年1月于本院行正颌手术治疗的34例患者为研究对象，采集患者术前术后 锥形束CT（CBCT）图像，在开源软件（3D Slicer）中，运用基于体素的图像配准技术，测量髁突的位置 和形态学变化，并采用同类相关系数（ICC）对该方法的稳定性进行评估。结果 髁突轴向旋转的ICC为 0.976，轴向平移的ICC为0.984，表面变化测量的ICC为0.947。结论 基于CBCT图像新配准技术在测量髁突 旋转、位移和形态变化方面具有很大的稳定性，为颞下颌关节疾病的诊疗提供了可靠的评估。     

Application of MRI in indirect temporomandibular joint injury without condylar fracture

Objective： To discuss the application of MRI in indirect temporomandibular joint injury without condylar fracture. Methods： MRI examination on temporomandibular joint was conducted in 28 patients with indirect injury to temporomandibular joint without condylar fracture. The scanning sequence included TIWI, PDWI on oblique sagittal section at both open and closed mouth positions, and T1WI, T2WI on oblique coronal section. The MRI appearance was analyzed by 2 senior radiologists. Results： Among the 56 temporomandibular joints of28 patients, 35 joints exhibited pathological changes on MRI, in which there were 9 bone injuries, 21 articular disc dislocation, 24 intracapsular hematocele and hydrops. Conclusions： MRI can clearly reveal bone injury, articular disc dislocation as well as articular capsule abnormality in the indirect injury of temporomandibular joint without condylar fracture. It is highly advocated in clinical use.     

骨性Ⅲ类错的三维CT头影测量分析

目的：观察骨性安氏Ⅲ类偏的成人女性患者接受正颌手术后硬组织的三维改变。方法：5例接受外科手术（上颌Lefort 1型截骨术＋双侧下颌升支矢状劈开切骨术＋颏部成形术）的成人女性骨性安氏Ⅲ类患者,分别在术前1个月（T0）和术后6个月（T1）接受3DCT扫描。在CT后处理工作站中实现三维模型重建,并进行标记点的确定和变量的测量以完成三维头影测量分析。结果：所有患者的下颌前突均得到显著纠正。不仅偏颌得到改善（Pg-dev）,而且平面的偏斜也得到矫正（Ore/OP）。硬组织的改变在前后向（SNA,ANB）、垂直向（Ans-Me,MP/SN）和水平向（Gc-Gc＇,Go-Na-Go＇）方面均有显著改变。结论：①骨性Ⅲ类偏患者手术前后,硬组织在三维分析中的各个方面均有明显改变;②与传统的二维头影测量分析相比,三维头影测量分析可以更加全面的反映出颅颌面部的特征,具有较大的临床意义。     

Orofacial myofunctional changes in skeletal Class III patients after bimaxillary orthognathic surgery

The aim of this study is to investigate the effect of bimaxillary orthognathic surgery on orofacial myofunctional changes in skeletal class III patients.35 patients who received Le Fort I maxillary advancement osteotomy and mandibular SSRO setback were included in this study. Facial expression function was analyzed by “placid” or “smile” expressions using chL-chR, ∠chRnchL, and ls-li. Occlusal force and balance were analyzed using a T-scan III digital occlusal analysis system. Maximum mouth opening (MMO) was measured prior to surgery and 2/14/28/42/90/180/360 days after surgery.After surgery, patients recovered facial expressions in no less than 3 months for both the “placid” or “smile” facial expression. Patients obtained significantly improved ‘smile’ expressions 3 months after the operation compared to preoperative “smiles”, and this improvement remained stable 12 months after the operation. Occlusal force was significantly decreased with the balance of occlusion lost immediately after surgery. These conditions gradually recovered, and patients finally obtained a more balanced and stronger occlusion [occlusion balance: 6.7 ± 2.7 mm vs. 4.1 ± 3.0 mm (day -7 vs. day 42); occlusion force: 19.6 ± 7.0 kg vs. 24.2 ± 9.3 kg (day -7 vs. day 180)]. However, patients had smaller postoperative mouth opening compared to preoperation opening during our follow-up.Our results confirmed that orthognathic surgery obstructs orofacial myofunctions of skeletal class III patients in the short-term. In the long-term, orthognathic surgery results in more stable and balanced orofacial myofunctions. By understanding the process of functional recovery of orofacial muscles after orthognathic surgery, we hope to accelerate patient's recovery from surgery.     

骨性安氏Ⅲ类错患者行正颌手术后其口腔功能间隙的改变

目的:探讨骨性安氏Ⅲ类错患者行正颌手术后,口腔功能间隙面积的改变,了解口腔功能间隙与牙颌畸形发生的关系,为正颌临床诊断治疗提供有益的参考。同时研究口腔功能间隙的改变对术后保持与防止复发提供理论依据。方法:对在我院就诊的共20例骨性安氏Ⅲ类错患者进行研究,采用定位X线头影测量分析的方法,通过患者治疗前后的对照,比较正颌术后口腔功能间隙的改变。结果:骨性安氏Ⅲ类错患者行正颌手术后较术前1周口腔功能间隙减小(P<0.05),有统计学差异。下颌后退量与口腔功能间隙减少量存在明显的正相关性。结论:骨性安氏Ⅲ类错患者,经正颌治疗后,口腔功能间隙矢状向面积有所减小,其直接原因可能是正颌手术后退下颌骨造成的,并且口腔功能间隙变化量与下颌骨后退距离存在正相关性。     

Mini suture anchor: An effective device for reduction and fixation of displaced temporomandibular joint disc with intracapsular condylar fracture

PurposeThe main aim is to provide clinical reference for the application of mini suture anchor in the reduction and fixation of displaced temporomandibular joint (TMJ) disc with intracapsular condylar fracture.MethodsFrom October 2018 to October 2019, 21 patients (31 sides) with intracapsular condylar fractures and articular disc displacement from West China Hospital of Stomatology, Sichuan University were included. The selection criteria were: (1) mandibular condylar fractures accompanied by displacement of the TMJ disc, confirmed by clinical examination, CT scan and other auxiliary examinations; (2) indication for surgical treatment; (3) no surgical contraindications; (4) no previous history of surgery in the operative area; (5) no facial nerve injury before the surgery; (6) informed consent to participate in the research program and (7) complete data. Patients without surgical treatment were excluded. The employed patients were followed up at 1, 3, 6 and 12 months after operation. Outcomes were assessed by success rate of operation, TMJ function and radiological examination results at 3 months after operation. Data were expressed as number and percent and analyzed using SPSS 19.0.ResultsAll the surgical procedures were completed successfully and all the articular discs were firmly attached to the condyles. The articular disc sufficiently covered the condylar head after the fixation. The fixation remained stable when the mandible was moved in each direction by the surgeons. No complications occurred. The functions of the TMJ were well-recovered postoperatively in most cases. CT scan revealed that the screws were completely embedded in the bone without loosening or displacement.ConclusionMini suture anchor can provide satisfactory stabilization for the reduced articular disc and also promote the recovery of TMJ functions.     

A New Face by Combined Surgery for Patients with Complex Dentofacial Deformity

BACKGROUND: This article aims to present and discuss 53 patients who received a new identity because of major changes to the face after treatment with bimaxillary osteotomy, concomitant maxillomalar augmentation, genioplasty, and rhinoplastic procedures for their complex dentofacial skeletal deformity and class 3 malocclusion. METHODS: During a 12-year period (January 1993 to April 2005), more than 500 patients with dentofacial deformities and malocclusions have undergone orthognathic surgery performed by a team consisting of the same plastic surgeons and orthodontists. Among this group, 53 patients (30 women and 23 men) underwent surgery for both aesthetic and functional concerns. The mean patient age was 20.4 years (range, 17-28 years). All the patients were treated with bimaxillary osteotomy, concomitant maxillomalar augmentation, osseous genioplasty, and rhinoplastic procedures in the same session. The patients were followed 12 to 44 months by the plastic surgeon, and at least 1 year by the orthodontist. RESULTS: There was no orthognathic relapse or other major complications requiring reoperation. There was prolonged nerve anesthesia or hypoesthesia that resolved within 6 months for 4 patients (7.5%), a short period of anesthesia or hypoesthesia that resolved within 4 weeks for 11 patients (20.7%), a wide alar base in 3 patients, and a slight deviation of the cartilage septum in 2 patients. CONCLUSION: In one session, five different procedures can be performed without any problem, each of which can produce major changes to the face while maintaining the whole facial harmony. The authors determined that these dramatic positive outcomes for the combined procedure can easily be tolerated and accepted by all their patients. However, the patients have had difficulty with their family or friends accepting their new appearance, and even have had to change their photos on identification cards. This is encouraging for the management of new patients in the future.     

两种正颌手术方法治疗骨性安氏Ⅲ类错（牙合）稳定性的研究

目的：应用计算机及WINCEPH软件测量X线头颅定位侧位片,探讨不同术式治疗骨性安氏III类错（牙合）效果的稳定性。方法：62例骨性安氏III类错（牙合）患者36例接受下颌升支矢状劈开术（sagittal split ramus osteotomy,SSRO）,26例接受下颌升支垂直骨切开术（intraoral vertical ramus osteotomy,IVRO）,分别在手术前（T0）、手术后1个月（T1）、手术后6个月（T2）、手术后18个月以上（T3）拍摄头颅定位侧位片,利用计算机测量其各个阶段12个测量点矢状向变化,进行统计学分析。结果：SSRO术后出现与手术目的相反方向的复发;IVRO术后出现与手术目的相同方向的移位,无明显差异。结论：SSRO和IVRO方法各有其优缺点,术后移位率无明显差异,临床上选择哪一种术式应该根据患者具体情况来确定。     

数字化正颌外科技术在半侧颜面短小畸形矫治中的应用

目的探讨数字化正颌外科技术在半侧颜面短小畸形(HFM)患者正颌手术矫治中的应用效果及患者满意度。方法回顾性分析2017年1月至2020年5月武汉大学口腔医院正颌与唇腭裂整形外科收治的HFM患者的临床资料。术前应用数字化正颌外科技术设计手术方案,三维打印中间导板及终末导板用于术中定位上、下颌骨含牙骨块的位置。术后第5天拍摄面部标准照和头颅CT,与术前设计方案拟合,以测量上颌骨各标志点及颏前点术后实际位置和术前设计位置与参考平面距离的误差,数据以±s表示,采用配对t检验进行比较,P<0.05表示差异有统计学意义。采用间隔尺度法调查患者术后第7天及6个月的满意度(满分为100分)。结果共纳入9例HFM患者,男5例,女4例,年龄(25.8±3.8)岁。其中患侧位于左侧6例,位于右侧3例。所有患者手术实施顺利,术中导板就位良好,上、下颌骨含牙骨块按照术前设计的位置准确移动并固定,术中未发生颌骨意外骨折等情况。术后5 d拍摄的面部标准照和CT显示,患者口颌系统功能恢复良好,无明显并发症发生。上颌骨各标志点及颏前点术后实际位置和术前设计位置与参考平面距离的误差,差异均无统计学意义(P>0.05),其中上颌骨左侧第一磨牙近中颊尖点误差最大,为(0.92±0.34)mm。患者术后第7天满意度评分为(83.2±2.7)分,术后6个月评分为(73.8±2.5)分。结论数字化正颌外科技术能够精确指导手术,有效矫正HFM患者咬合平面、牙列中线及颏中线偏斜等畸形,患者术后初期满意度较高,但6个月后有所下降。     

Condylar and disc positions after sagittal split ramus osteotomy with and without Le Fort I osteotomy.

PURPOSE: The purpose of this study is to examine the changes in temporomandibular joint (TMJ) morphology and clinical symptoms after sagittal split ramus osteotomy (SSRO) with and without a Le Fort I osteotomy. SUBJECTS AND METHODS: Of 45 Japanese patients with mandibular prognathism, 23 underwent SSRO and 22 underwent SSRO in combination with a Le Fort I osteotomy. The TMJ symptoms and joint morphology, including disc tissue, were assessed preoperatively and postoperatively by magnetic resonance imaging (MRI) and axial cephalography. RESULTS: There were significant differences between pre- and postoperative horizontal changes in the condylar long axis on the right side in the group undergoing SSRO (sagittal split ramus osteotomy) alone. However, there were no other significant differences in pre- and postoperative measurements in this group as compared with the group receiving SSRO plus Le Fort I osteotomy, and the preoperative disc position could not be changed in either group. CONCLUSION: These results suggest that SSRO, either with or without Le Fort I osteotomy, could not change the preoperative disc position or correct anterior disc displacement, although these procedures did improve the symptoms associated with TMJ dysfunction.     

双颌手术矫治下颌前突的临床效果研究

目的探讨应用双颌手术联合正畸治疗矫治骨性Ⅲ类下颌前突畸形的临床效果。方法自2015年7月至2020年6月,辽宁省人民医院口腔科对7例骨性Ⅲ类下颌前突畸形患者,实施规范的术前X线头影测量分析、诊断,以及术前正畸、正颌外科手术、术后正畸和随访疗效评估的诊治程序进行双颌手术正颌外科联合正畸治疗。采用基本术式为LefortⅠ型切开截骨术(LefortⅠostotomy)整体前移上颌骨、双侧下颌升支矢状劈开截骨术后退下颌。结果所有患者术后伤口均一期愈合,无感染及骨坏死发生;随访1~3年,所有患者的上下颌骨关系正常,牙弓形态及牙颌曲线正常,牙排列整齐,咬关系及咀嚼效能良好,面部改善较明显,均达到了患者的期望。结论按照标准规范的正畸正颌联合诊治程序,应用双颌手术联合正畸治疗矫治骨性Ⅲ类下颌前突畸形患者,在临床上可取得一定的诊疗效果,不仅恢复了患者的咬关系和咀嚼功能,更改善了颜面外形和提高了生活质量。     

Skeletodental factors affecting chin point deviation in female patients with class III malocclusion and facial asymmetry: a three-dimensional analysis using computed tomography.

OBJECTIVE: Three-dimensional computed tomography (CT) was used to investigate which skeletodental factors are related to chin point deviation of facial asymmetry in skeletal class III malocclusion (SCIII) patients. STUDY DESIGN: Forty Korean adult female patients with SCIII, who had a three-dimensional CT taken 1 month before orthognathic surgical surgery, were assigned to group 1 (symmetry) or group 2 (asymmetry) according to the amount of chin point deviation from facial midline. Midfacial, mandibular, and cranial base variables were measured with software and statistically analyzed. RESULTS: Group 2 showed higher positions of the upper canine and first molar, shorter ramus height, more superior-posterior positioning of gonion (Go) on the deviated side, and more mesial inclination of the ramus and medial positioning of Go on the opposite side. CONCLUSION: Facial asymmetry in SCIII patients occurs due to greater growth and mesial inclination of the ramus and greater maxillary vertical excess in the opposite side.     

Real-time orthognathic surgical simulation using a mandibular motion tracking system.

We developed a new orthognathic surgical simulation system able to predict both occlusal correction and mandibular repositioning in three dimensions. This system uniquely integrates the real motion of the dental cast model with the virtual motion of the reconstructed cranio-facial model. The skeletal change of the mandibular osteotomy is simulated on the PC monitor while the occlusal change is confirmed by checking the cast model on the simulator. The simulation process is easily repeated and the operator can make several attempts to determine the final mandibular position. The occlusal relationship at the simulated mandibular posture is registered and the occlusal wafer splint, which ensures intermaxillary fixation, is fabricated on the simulator. This surgical simulation system appears to satisfy clinical demands well and is an important facilitator of communication between orthodontists and surgeons. Here, we outline the system and apply it to a demonstration case of orthognathic surgery.     

Late management of cleft lip and palate problems: a joint orthodontic/surgical approach

Three patients are presented from a larger case series of adolescent cleft lip and palate patients to illustrate a combined approach to the treatment of severe facial and dentoalveolar discrepancy. The following treatment regime was employed: orthopaedic expansion of the maxillary dentoalveolus; tertiary bone grafting of the alveolar cleft; upper and lower dental arch alignment and decompensation; and orthognathic surgery to correct the skeletal defect by means of a maxillary single unit advancement. The advantages of tertiary grafting (when secondary grafting has not been carried out) in the orthodontic and surgical management of these patients is discussed.     

Aesthetic Male Facial Skeletal Surgery

Craniofacial surgery concepts developed originally for reconstruction may also be applied to aesthetic surgery. The facial skeleton is an important component of appearance and may be modified using common craniofacial surgery techniques. Three representative male patients are presented, who each desired an improvement in his appearance. The techniques used were different and combined orthognathic and remodeling procedures. Aesthetic male facial skeletal surgery was beneficial in these selected cases. The results were well received and without complications. Surprisingly, we have found that male skeletal aesthetic patients did not have unrealistic expectations and were pleasant to manage pre- and postoperatively.     

The significance of condylar position using rigid fixation in orthognathic surgery

Rigid fixation in orthognathic surgery has major advantages, particularly the elimination of postoperative intermaxillary fixation, which makes the procedure more comfortable for the patient. The main disadvantage of rigid fixation in these procedures is that errors in the position of bony segments and dislocations of the mandibular condyle during surgery may result in errors of the occlusion and cause adverse effects on the temporomandibular joint. When rigid fixation is used, the presurgical position of the condyles should be maintained. The principles of condylar positioning are described.     

安氏Ⅲ类错[牙合]的下颌形态研究

目的：采用几何形态测量法来探讨骨性Ⅲ类错[牙合]下颌形态的特征。方法：随机选取恒牙初期骨性Ⅲ类与Ⅰ类错[牙合]患者头颅侧位片各30张,描记下颌的16个标志点,数字化后采用Procrustes重叠法、薄板曲线法、欧式距离矩阵法和常规头影测量法,以骨性Ⅰ类错[牙合]患者作为对照组,对骨性III类错[牙合]与Ⅰ类错[牙合]进行两组间t检验从而对其下颌形态进行比较。结果：Ⅲ类错[牙合]与Ⅰ类错[牙合]相比,下颌形态有差异（P〈0.05）,Ⅲ类错组髁状突长度、升支高度、下颌体长度增加,颞颌关节、颏部都靠前,下切牙舌倾。结论：III类错[牙合]的下颌形态有其自身特点,并影响Ⅲ类错的形成。     

Quantitation of chondroitin-sulfates, disaccharides and hyaluronan in normal, early and advanced osteoarthritic sheep temporomandibular joints

OBJECTIVE: To determine the relationship between synovial fluid, chondroitin sulfate disaccharide and hyaluronic acid to differing degrees of experimental temporomandibular joint (TMJ) osteoarthritis (OA). DESIGN: Twenty-four merino sheep were divided into three groups and had different TMJ surgical procedures to produce OA. Group I; control (six sheep), Group II; disc perforation (nine sheep) and Group III; disc perforation and articular damage (nine sheep). Synovial fluid was collected initially and at sacrifice at 3 months. Chondroitin 4-sulfate, chondroitin 6-sulfate and hyaluronic acid were measured and correlated to the OA histologic score. RESULTS: The chondroitin-sulfate levels were significantly increased (Group I to Group II P< 0.001; Group I to Group III P< 0.001), the hyaluronic acid levels decreased (Group I to Group II P< 0.01; Group I to Group III P< 0.01) with the increasing OA score. CONCLUSION: Chondroitin-sulfate and hyaluronic acid show a correlation with surgically created TMJ osteoarthritis in sheep model.     

内镜辅助肋骨-软骨移植重建髁突与同期正颌手术的临床研究

目的 探讨内镜辅助肋骨-软骨移植重建髁突与同期正颌手术治疗严重颞下颌关节病变及牙颌面畸形的效果. 方法 于术前对患者进行临床检查和治疗设计,术中行Le Fort Ⅰ型截骨术、下颌支矢状骨劈开术、髁突等关节区病变的处理、内镜辅助下肋骨-软骨移植和颏成形术,术后进行随访. 结果 2003年9月至2005年12月,于临床应用15例,所有患者同期手术均顺利完成.术中、术后均无严重出血、神经损伤、受区感染等严重并发症发生.术后随访29～52个月,平均31.8个月,所有患者面容均显著改善,关节功能良好,且无关节区疼痛等主观症状,患者对手术疗效满意.术后张口度平均为33.6 mm,侧向运动度为0～6 mm. 结论 选择合适的适应证、设计合理的手术方案,内镜辅助髁突重建同期正颌手术效果较好.