青少年单侧后牙正锁牙合畸形患者双侧髁突在关节窝内位置及其形态变化研究

目的　观察并分析青少年单侧后牙正锁牙合畸形患者的双侧髁突在关节窝内位置及其形态变化。方法　选择2016年8月至2018年8月到南方医科大学口腔医院正畸科就诊的单侧后牙正锁牙合畸形患者35例为观察组,另选择同期就诊的后牙发育正常患者35例作为对照组,所有患者行锥形束CT（CBCT）扫描。分别比较两组患者的双侧关节间隙指标 ［包括关节前间隙（AS）、关节上间隙（SS）、关节后间隙（PS）］测量值及髁突形态指标（包括高度、内外径、前后径、体积、表面积）测量值,并对两组患者间的髁突形态不对称指数进行比较。结果　（1）对照组患者双侧关节间隙各指标（AS、SS、PS）测量值比较,差异均无统计学意义（P＞0.05）;观察组患者双侧关节间隙各指标测量值比较,AS锁牙合侧低于非锁牙合侧、PS锁牙合侧高于非锁牙合侧,差异均有统计学意义（P＜0.05）,而SS两侧差异无统计学意义（P＞0.05）。（2）两组患者双侧髁突形态各指标（高度、内外径、前后径、体积、表面积）测量值比较,差异均无统计学意义（P＞0.05）。（3）观察组患者髁突高度不对称指数明显高于对照组,差异有统计学意义（P＜0.05）,而内外径不对称指数、前后径不对称指数两组患者间比较,差异无统计学意义（P＞0.05）。结论　青少年单侧后牙正锁牙合畸形患者的双侧髁突在关节窝内位置发生改变,锁牙合侧与非锁牙合侧相比更靠前,但髁突形态基本对称,而CBCT能够为患者的锁牙合畸形诊断以及正畸方案提供可靠依据。     

基于CBCT分析正畸前后单侧后牙正锁牙合的髁突变化

目的采用锥形束CT(CBCT)分析单侧后牙正锁牙合患者的双侧髁突在关节窝内位置及其形态,探讨其对患者髁突位置及形态的影响和改善情况。方法选择2012年2月至2015年8月间我院收治的15例单侧后牙正锁牙合患者为实验组,选择同期符合安氏Ⅰ类轻度拥挤错牙合患者15例为对照组。所有研究对象均进行面部锥形束CT拍摄,对双侧髁突运用3D Exam vision软件进行三维重建,对7个不同测量值进行统计学分析。结果正畸治疗前,对照组两侧在关节窝内的位置及髁突形态比较,差异均无统计学意义(P>0.05);实验组中的正锁牙合侧关节窝深度、髁突高度均大于非锁牙合侧,差异具有统计学意义(P<0.01)。解除正锁牙合矫正稳定3个月后,实验组正锁牙合侧关节前间隙变化明显小于治疗前,关节后间隙明显大于治疗前,差异具有统计学意义(P<0.05);实验组非锁牙合侧治疗前后髁突形态及位置差异均无统计学意义(P>0.05);实验组正锁牙合侧与非锁牙合侧相比,关节窝深度和髁突高度差异具有统计学意义(P<0.01)。结论单侧后牙正锁牙合可影响髁突形态及其位置的改变,矫治正锁牙合并稳定保持3个月后,锁牙合侧关节有向前下移动的趋势,但髁突形态变化不明显。     

基于锥形束CT分析骨性Ⅲ类高角伴下颌偏斜患者髁突形态和位置的研究

目的 应用锥形束CT（CBCT）对比分析骨性Ⅲ类高角伴下颌偏斜患者与个别正常牙合患者髁突的形态和位置。方法 选取2017年9月至2019年9月于上海交通大学医学院附属第九人民医院口腔正畸科就诊的患者40例，其中骨性Ⅲ类高角伴下颌偏斜患者20例（偏斜组），个别正常牙合患者20例（对照组）。所有患者于治疗前拍摄CBCT，使用Invivo 5.0软件对CBCT影像进行三维重建及测量，并比较两组患者两侧髁突形态和位置的差异。结果 （1）偏斜组患者两侧髁突形态和位置指标测量值比较发现，在髁突形态方面，偏斜侧髁突最大轴面面积、髁突高度、髁顶高度均比非偏斜侧小，差异均有统计学意义（均P < 0.05）。在髁突位置方面，偏斜侧髁突外间隙、上间隙和后间隙比非偏斜侧小；偏斜侧髁突前间隙、内间隙及髁突外突距比非偏斜侧大，差异均有统计学意义（均P < 0.05）。（2）对照组两侧髁突形态和位置指标测量值比较，差异均无统计学意义（均P > 0.05）。（3）偏斜组两侧髁突形态和位置指标测量值分别与对照组比较发现，在髁突形态方面，偏斜组偏斜侧髁突高度比对照组大，最大轴面面积比对照组小；非偏斜侧髁突高度大于对照组，差异均有统计学意义（均P < 0.05）。在髁突位置方面，偏斜组偏斜侧髁突上间隙小于对照组，髁突内间隙、前间隙、髁突外突距及髁突与正中矢状面距大于对照组，差异均有统计学意义（均P < 0.05）。结论 骨性Ⅲ类高角伴下颌偏斜患者双侧髁突的形态和位置具有明显的不对称性，偏斜侧髁突形态较对侧小，并向后上外方向移位。骨性Ⅲ类高角伴下颌偏斜患者的髁突高度比个别正常牙合患者大。     

成人安氏Ⅰ类错(牙合)正畸前、后髁突形态的变化

目的:运用锥形束CT(CBCT)分析成人安氏Ⅰ类错(牙合)正畸治疗前、后髁突形态在三维方向上的变化.方法:选取25例临床无口腔颞下颌关节紊乱症状的成人安氏Ⅰ类错(牙合)患者(男5例,女20例)正畸治疗前、后双侧颞下颌关节的CBCT影像,应用Mimics10.01软件对CBCT影像进行三维重建,测量正畸治疗前、后髁突的高度、最大轴位平面和最大矢状位平面的面积及骨密度,三维髁突及上部三维髁突的体积及骨密度,采用SPSS 19.0软件包对数据进行统计学分析.结果:最大轴位平面和最大矢状位平面的面积和骨密度值较治疗前显著降低(P＜0.05);三维髁突体积及骨密度和上部三维髁突骨密度较治疗前显著降低(P＜0.05).结论:成人安氏Ⅰ类错(牙合)正畸治疗前、后髁突发生适应性的改建.     

单侧后牙正锁(牙合)患者下颌侧方运动时的髁突轨迹特征

目的:探讨单侧后牙正锁(牙合)患者在下颌侧方运动过程中髁突的运动轨迹特征及其与正常(牙合)者之间的差异.方法:选取单侧后牙正锁(牙合)患者26例为实验组,个别正常(牙合)26例为对照组,应用髁突运动轴图描记仪(computer aided diagnosis axiograph,CADIAX)记录下颌侧方运动时髁突的运动轨迹.实验数据采用SPSS10.0软件包分析,选用成组t检验、配对t检验或秩和检验比较组间差异有无统计学意义.结果:实验组下颌侧方运动过程中髁突轨迹不流畅变异大,两侧运动轨迹不对称.非锁(牙合)侧髁突的矢状位移、垂直位移以及空间最大位移大于锁(牙合)侧和对照组,水平位移小于后者,差异有统计学意义(P<0.05);非锁(牙合)侧髁突的矢状倾斜度大于锁(牙合)侧和对照组,水平倾斜度小于后者,差异有统计学意义(P<0.05).结论:单侧后牙正锁(牙合)患者下颌侧方运动过程中两侧髁突运动轨迹不对称.     

单侧后牙锁患者前伸及后退髁突运动轨迹的研究

目的探讨单侧后牙锁者在下颌前伸、后退运动过程中髁突运动轨迹的特征及其与正常者之间的差异。方法选择单侧后牙锁患者24例和个别正常25例,应用髁突运动轴图描记仪(computer aided diagnosis axiograph,CADIAX)记录下颌前伸、后退运动时髁突的运动轨迹。结果实验组在下颌前伸、后退运动过程中髁突轨迹曲折、不流畅、重合性差,两侧髁突运动不对称、侧方位移增大;其锁侧在矢状方向和空间位移上以及髁突矢状面倾斜度小于非锁侧(P<0.05),锁侧髁突矢状面倾斜度较对照组小(P<0.05),在髁突位移5mm处水平面髁突倾斜度大于对照组(P<0.05)。结论单侧后牙锁者下颌前伸、后退运动时两侧髁突运动不对称,侧方位移增加。     

成人单侧后牙反(牙合)患者髁突的对称性及矫治后髁突位置的变化

目的：探讨成人单侧后牙反[牙合]患者髁突的对称性及矫治后髁突位置（R）的变化。方法：21例成功矫治的单侧后牙反[牙合]成年患者作为实验组,男10例,女11例,年龄18～23岁,平均21.8岁。21例安氏Ⅰ类错[牙合]患者作为对照组,男10例,女11例,年龄19～23岁,平均22.1岁。实验组矫治前后与对照组均拍摄全颌曲面断层片和双侧矫正薛氏位片,测量髁突的不对称指数和髁突在关节窝中的相对位置。结果：实验组两侧髁突高度（CH）不对称,与对照组相比,CH的不对称指数明显增大（P〈0.05）。实验组矫治前后两侧髁突在关节窝中的位置均无显著性差异,但与矫治前相比,矫治后非反[牙合]侧髁突相对位置由前位趋于正中位（R由13.52减小为9.48）。结论：成人单侧后牙反[牙合]患者的髁突形态存在不对称性,而髁突位置相对对称,颞下颌关节可随咬合关系和下颌骨位置的变化发生改建;正畸治疗后髁突位置更加协调。     

单侧后牙反(牙合)患者髁状突及下颌升支对称性的螺旋CT研究

目的：探讨单侧后牙反[牙合]成年患者髁状突及下颌升支的对称性。方法：对22例单侧后牙反[牙合]患者进行螺旋CT扫描、多层面重建和相关参数测量,并进行统计分析。结果：双侧髁突内、外突面积的差异无统点的距离,髁突内倾角及下颌角点的距离有显著差异,但髁突左右径、髁状突最大横截面积、下颌支高度及下颌支冠状位最大计学意义。结论：单侧后牙反[牙合]患者左右侧髁状突及下颌支的位置不对称,但髁突及下颌升支大小无显著差异。     

单侧完全性唇裂患者行术前鼻牙槽塑形治疗后牙槽突变化的三维测量分析

目的 应用三维测量分析法对单侧完全性唇裂患者行术前鼻牙槽塑形（PNAM）治疗后牙槽突的变化进行评价。方法 选取2013年11月-2015年6月于广西医科大学附属口腔医院完成PNAM治疗的单侧完全性唇裂患者30例,分别于PNAM治疗前后制取腭部口腔石膏模型,以锥形束CT（CBCT）采集DICOM数据,应用Mimics 15.0进行三维重建,并测量牙槽突裂隙宽度、牙槽突末端宽度、上唇系带中线距离、牙槽突移动距离、牙槽突长度,采用SPSS 17.0软件进行对比分析。结果 PNAM治疗前后,患者的牙槽突裂隙宽度、上唇系带中线距离明显缩小（P< 0.05）,牙槽突末端宽度差异无统计学意义（P>0.05）,较大侧牙槽突移动距离明显大于较小侧（P<0.05）,双侧牙槽突长度均有明显增长（P<0.05）,较大侧牙槽突增长量明显大于较小侧（P<0.05）。结论 印模+CBCT扫描法可以获得准确的牙槽突三维数据,经过PNAM治疗后,牙槽突形态得到显著改善。     

单侧后牙缺失对髁突形态影响研究现状

单侧后牙长期缺失不修复,不仅会影响咀嚼习惯,而且易引起继发性咬合紊乱。既往研究表明,后牙缺失与颞下颌关节（TMJ）形态改建相关。髁突作为承力的主要区域,是TMJ改建最为活跃的部分。下面就近年来单侧后牙缺失对髁突形态影响的研究现状做一综述。     

Dental injuries in association with mandibular condyle fractures

Abstract A total of 356 patients with mandibular condyle fractures were studied regarding associated dental injuries. One third of the patients had injured teeth, on average, 3.7 teeth had been injured per accident. Dental traumas were distributed equally between the anterior (incisors and canines) and posterior teeth (premolars and molars) in both jaws. In unilateral condylar fracture cases maxillary dental injuries involved more often premolars and/or molars of the fracture side than those of the non-fracture side. The mean number of dental traumas in the mandible was higher in cases of simultaneous mandibular body fracture than without, whereas the presence of mandibular body fracture did not affect number of associated dental injuries in the maxilla. The dental injuries were mostly to hard tissue (78%), which were commonest in men, 20 to 29 years of age, and in victims of violence or fall accidents. Severe dental injuries in association with mandibular condyle fractures were more common in accidents due to traffic and miscellaneous causes than in those due to violence. Severe dental injuries were more often encountered when simultaneous mandibular body fracture was present than when it was not and more so in bilateral than unilateral condylar fracture cases. The most important factor correlating with the severity of dental injuries was the presence of bilateral condylar fracture.     

采用锥形束CT分析安氏Ⅱ类1分类错牙合患者Twin-block矫治前后颞下颌关节的变化

目的 运用锥形束CT（CBCT）分析安氏Ⅱ类1分类错牙合在Twin-block矫治前后颞下颌关节位置及形态结构在三维方向上的变化。方法 选取20例处于生长发育高峰前期或高峰期的安氏Ⅱ类1分类错牙合患者,拍摄其功能矫治前后双侧颞下颌关节的CBCT片,运用InVivoDental软件对CBCT片进行三维重建并测量线距和角度,对测量结果进行统计学分析。结果 与治疗前相比,治疗后矢状向关节前间隙减小,关节上间隙和后间隙增大,冠状向关节上间隙增大（P<0.01）;髁突高度、矢状向髁突角度、横断面髁突前后径增加（P<0.01）。结论 采用Twin-block矫治器治疗安氏Ⅱ类1分类错牙合患者后,髁突在关节窝的位置和髁突部分骨性结构发生了一定程度的改变,髁突有新骨沉积,高度增加,在关节窝内的位置更向下和向前。CBCT的应用使颞下颌关节结构的变化得以量化,能对正畸治疗效果进行客观评价。     

小型猪一侧失牙及义齿修复后颞下颌关节的组织病理学观察

目的：观察一侧失牙及义齿修复对小型猪颞下颌关节（temporomandibular joint，TMJ）组织结构的影响。方法：11只小型猪随机分为空白组（2只）、拔牙组（4只）、修复组（5只），将拔牙组和修复组左侧后牙全部拔除，修复组并于拔牙后3个月进行义齿修复。小型猪一侧失牙6个月时处死，解剖TMJ并制作光镜（HE染色）和透射电镜标本，观察其组织结构改变。结果：拔牙组和修复组小型猪双侧TMJ均发生不同程度的退行性改变。髁突软骨表面带玻璃样变性、断裂、剥脱；肥大带下陷成乳突样，软骨细胞成簇；骨小梁破坏呈蚕蚀状。关节盘胶原纤维变性、紊乱、断裂，盘后组织出现明显软骨化生。髁突软骨瘀斑、凹陷、剥脱的超微病理特征分别是细胞变性、凋亡、坏死。结论：长期一侧失牙可导致双侧TMJ退行性变，及时义齿修复可减轻TMJ的病理损伤。     

Comparison of internal derangements of the TMJ with occlusal findings

Two hundred five patients were examined because of temporomandibular joint pain and dysfunction. Arthrograms were performed on 222 joints (188 unilateral and 17 bilateral). No significant differences were found between arthrographic groups with respect to Angle classification, horizontal and vertical overlap, posterior tooth wear, missing posterior teeth, cuspid-protected occlusion, balancing-side contacts, deflective occlusion, and clenching of the teeth. Tilted teeth on the contralateral side were more common in cases of reducing meniscal dislocation than in cases of normal meniscus position or of nonreducing meniscal dislocation.     

特发性髁突吸收患者髁突形态特征的CBCT研究

目的:探讨特发性髁突吸收(ICR)患者髁突的三维形态特征.方法:选取符合ICR诊断的患者26例为实验组,无关节疾患的骨性Ⅰ类错(牙合)患者26例为对照组,对颞下颌关节(TMJ)行CBCT扫描,利用Mimics 17.0行三维重建,测量髁突大小及形态,并进行统计学分析.结果:实验组髁突体积、表面积变小(P＜0.01),前后径、内外径变短(P＜0.01),高度降低(P＜0.01),对照组及双侧发病组左右侧对比无明显差异(P＞0.05).结论:ICR患者髁突相比正常髁突,表现出三维方向上的形态改变,可用来评估ICR的进展、疗效及预后.     

Changes in parathyroid hormone-related protein and 3-dimensional trabecular bone structure of the mandibular condyle following mandibular distraction osteogenesis in growing rats.

PURPOSE: Distraction osteogenesis (DO) is commonly performed for mandibular reconstruction during the growth period. We tested the hypothesis that parathyroid hormone-related protein (PTHrP) in mandibular condylar cartilage and underlying trabecular bone in growing individuals undergo changes in response to distraction forces. MATERIALS AND METHODS: Forty-eight 6-week-old male Sprague-Dawley rats were used. Animals underwent unilateral mandibular distraction using a distractor that we devised, and unoperated animals were evaluated as controls. DO procedure was performed: 3 days' latency period, 0.4 mm/day rate, total 4.0 mm. Changes in cartilage morphology, PTHrP activity, and 3-dimensional trabecular bone structure changes measured by micro-computed tomography were examined at 0, 2, 4, and 6 weeks of consolidation. RESULTS: A marked irregularity was noted in the superior portion of the distracted side's condylar cartilage that resolved after distraction ceased. PTHrP was more strongly expressed in the hypertrophic layer of condylar cartilage on the distracted side than in controls, up to 6 weeks after the end of distraction. Subchondral trabecular bone volume, percent bone volume, and trabecular number in the superior and posterior regions of the condyle decreased significantly by 2 weeks after distraction. These parameters returned to normal in the posterior condyle, but not in the superior part of the condyle by 6 weeks following distraction. CONCLUSION: These results suggest that unilateral mandibular distraction in growing rats causes temporary morphologic alterations of trabecular bone structure on the distracted side accompanied by increased production of PTHrP in the mandibular condyle.     

Impact of posterior occlusal support on the condylar position

The purpose of this study was to investigate condylar displacement related to the loss of posterior occlusal support. Each of 23 subjects received one occlusal adjusted splint that covered all teeth from the right to the left second mandibular molar. None of the subjects had a third molar and none of them had a missing tooth or showed tooth mobility. The splint was inserted and vertical and horizontal condylar position was measured by an ultrasonic motion analyser. The splint was then unilateraly shortened tooth-by-tooth up to the canine tooth and the measurement was repeated after each shortening. Cutting off the splint's second molar on one side lead to a slight ipsilateral cranial motion of the condyle if subjects clenched with maximum voluntary force. If the second and first molar were cut off, a noticeable cranial condylar movement of about 0.3 mm was observed even when teeth occluded with low force. These results suggest that loss of posterior occlusal support as it happens in routine oral rehabilitation leads to a noticeable cranial condyle movement during registration, even if the clenching force is low.