偏侧咀嚼对生长发育期大鼠髁突软骨细胞热休克蛋白70表达的影响

目的:初步探讨偏侧咀嚼致颞下颌关节病的致病机理。方法:间断磨除大鼠单侧上下颌磨牙至龈缘,建立生长发育期大鼠偏侧咀嚼模型,采用免疫组织化学方法检测正常对照组及实验组大鼠髁突软骨热休克蛋白70(HSP70)的表达。结果:正常组大鼠髁突软骨各带(表面带、增殖带、肥大带、钙化软骨带)均存在HSP70基础表达;实验组大鼠咀嚼侧髁突软骨细胞HSP70表达增强,而非咀嚼侧髁突软骨细胞HSP70表达无明显改变。结论:偏侧咀嚼可使生长发育期大鼠髁突软骨细胞HSP70表达增强,其致病机理仍有待进一步研究。     

颞下颌关节骨关节病髁突软骨细胞雌激素受体β差异表达的研究

目的 探讨大鼠颞下颌关节骨关节病髁突软骨细胞雌激素受体β（ERβ）的差异表达。方法 25只SD大鼠随机分为实验组（15只）和对照组（10只）。实验组以去除左侧 部分关节盘的方法建立大鼠颞下颌关节骨关节病模型，术后3个月处死动物，取其髁突软骨细胞进行培养，采用免疫组化、逆转录聚合酶链反应、肽质量指纹谱（PMF）和Western blot等方法观察软骨细胞中ERβ蛋白和mRNA的表达。结果 PMF显示，ERβ是软骨细胞线粒体蛋白质组的成分，Western blot、逆转录聚合酶链反应和免疫组化结果显示，ERβ在实验组细胞和线粒体中表达水平较对照组降低（P<0.01）。结论 ERβ可能通过线粒体途径参与了颞下颌关节骨关节病的病理过程。     

渐进性咬合紊乱对大鼠颞下颌关节的影响

目的:探讨渐进性咬合紊乱对大鼠颞下颌关节的影响。方法:9只成年雄性SD大鼠,随机分为实验组(3只),操作对照组(3只)和空白对照组(3只)。实验组大鼠左侧上颌第一、第二磨牙间及右侧下颌第一、第二磨牙间分别嵌入正畸用皮圈推第一磨牙向近中,造成磨牙尖窝接触不吻合的渐进性咬合紊乱。术后6周取双侧颞下颌关节作HE染色观察。结果:操作对照组与空白对照组间未见差异,实验组与对照组相比髁突软骨中部增厚,后部变薄(P<0.05);关节盘中带和后带均明显变薄(P<0.05);实验组中部和后部软骨下骨小梁变得明显垂直于髁突表面排列。结论:渐进性咬合紊乱可以引起大鼠髁突软骨及软骨下骨小梁适应性改建。     

心理应激对大鼠髁突软骨中半胱氨酸天冬氨酸蛋白酶9表达的影响

目的探讨心理应激对大鼠髁突软骨中半胱氨酸天冬氨酸蛋白酶9（caspase-9）表达的影响。 方法将48只雄性SD大鼠用随机数表法随机分为6组：心理应激组（1、5和9周）及空白对照组（1、5和9周），每组各8只。应激组大鼠予以慢性不可预见性应激相应周数，应激完成后经旷场实验及糖水偏嗜度实验观察大鼠抑郁情况，数据通过重复测量的方差分析进行处理，随后处死相应时间点对照组及应激组大鼠，采用免疫组织化学染色及蛋白免疫印迹法了解髁突软骨细胞中caspase-9的表达情况，两对应时间点的数据通过两独立样本t检验进行分析。 结果实验中，心理应激组大鼠应激1周后即已开始出现总移动距离减少（t = 8.676，P = 0.011）、中间格停留时间缩短（t = 5.091，P = 0.041）、糖水偏嗜度降低（t = 10.150，P<0.001）等抑郁样改变，且大鼠髁突表面不整、出现了细胞胶原纤维松解的病理表现；应激5周时大鼠髁突胶原破坏持续存在，应激9周时大鼠髁突内软骨细胞减少，出现了无细胞的空白区域；且各时间点应激组髁突中caspase-9的表达均高于相应时间点的空白对照组，差异具有统计学意义（P<0.001）。 结论心理应激可导致大鼠出现活动减少、糖水偏嗜度降低等抑郁样改变，且大鼠髁突软骨中caspase-9的表达明显升高，这可能是应激导致颞下颌关节损伤的机制之一。     

下颌升支垂直截骨内固定术治疗髁突高位骨折

目的:比较手术和非手术方法治疗单侧下颌骨髁突高位骨折的临床效果。方法:19例髁突高位骨折患者,其中10例行下颌升支截骨内固定术+颌间牵引术(手术组),其余9例单纯行颌间牵引术(非手术组),随访0.5～1年。结果:手术组和非手术组之间比较,开口度及前伸运动度均无显著性差异(P>0.05);侧方运动度手术组优于非手术组,有显著性差异(P<0.01)。非手术治疗的患者,下颌骨平面不对称,X线片显示髁突的解剖位置欠佳。手术患者,下颌下区存在线形疤痕,但下颌骨平面对称,X线片显示患侧髁突与健侧形态相似。19例中无1例出现明显的颞下颌关节紊乱综合征。结论:采用下颌升支垂直截骨内固定术+颌间牵引术治疗下颌骨髁突高位复杂骨折,兼顾美观和功能,手术简便,不失为一种理想的治疗方法。     

髁状突游离再植治疗颞下颌关节髁突颈部骨折的临床研究

目的:探讨髁状突游离再植重建颞下颌关节治疗髁突颈部骨折的方法与疗效.方法:15例17侧髁突颈部骨折患者行髁状突游离再植鈦板复位固定的治疗,术后定期复查患者颞下颌关节功能和X线片检查.结果:患者术区伤口均一期愈合,追踪1～5年颞下颌关节无疼痛、弹响及明显功能障碍,2例面神经颞支有影响,1例轻度错牙合畸形. 结论:本法操作简单易行、复位准确、固定可靠,并发症少,适用于移位的髁突颈部骨折.     

兔下颌骨骨折对颞下颌关节影响的实验研究

目的 观察下颌骨骨折对两侧颞下颌关节的影响，探讨损伤后颞下颌关节修复的机制。方法 采用新西兰大耳白兔30只。随机分为术后48h和1、3、5、8周5个时相组及一个对照组。每组5只，用多功能打击装王造成各组动物左侧下颌骨骨折。夹板坚固内固定骨折断，按时项处死动物取左侧颞下颌关节，观察伤侧颞下颌关节的组织学变化。用免疫组化方法检测髁状突软骨内VEGF及其受体Flt1的表达。结果 各时项标本均可见到颞下颌髁状突及关节盘不同程度的损伤，髁状突肥大细胞检测到VEGF及其受体Flt1的表达。结论 下颌骨骨折可致颞下颌关节损伤。VEGF和其受体Flt1可能参与颞下颌关节损伤的修复。     

单侧前牙反牙合对大鼠下颌髁突软骨内CaR、PTHrP表达的影响研究

目的　探索单侧前牙反牙合（unilateral anterior crossbite,UAC）对大鼠下颌髁突软骨内钙离子敏感受体（calcium-sensing receptor,CaR）、甲状旁腺激素相关蛋白（parathyroid hormone-related protein,PTHrP）分子表达以及软骨细胞增殖和发育的影响。方法　选择6周龄雌性SD大鼠48只,根据实验时间点（2、4、8周）随机分为3大组,每大组再随机分为2组（对照组、UAC实验组）,每组动物数量8只。对SD大鼠施加UAC刺激,于2、4、8周后分别处死各组大鼠,对颞下颌关节软骨进行CaR、PTHrP、PTHrP 受体（PPR）分子的免疫组化染色,提取软骨内mRNA进行增殖标志分子、软骨细胞表型分子和终末分化相关分子的Real-time PCR检测。结果　UAC实验组大鼠髁突软骨2周时即开始出现CaR的表达增高,4周时继发有PTHrP的表达上调,但是其惟一受体PPR的表达从2周时即显著降低;增殖标志分子和软骨细胞表型分子的表达从2周时开始显著降低,终末分化相关分子的表达从4周开始显著增高。结论　UAC可导致下颌髁突软骨内CaR、PTHrP表达改变,进而影响软骨细胞的增殖和分化状态。     

血管内皮生长因子在颞下颌关节软骨细胞中的表达

目的：探讨血管内皮生长因子（vascular endothelial growth factor,VEGF）在颞下颌关节髁突软骨改建过程中的作用。方法：采用新西兰大耳白兔30只,分为术后24h和1、3、5、8周5个时间组及1个对照组,每组5只,用打击装置造成动物单侧下颌骨骨折,行钛合金小夹板坚强内固定,按时间分组处死动物取双侧颞下颌关节标本,观察髁突和关节盘软骨的组织学变化,应用免疫组化和原位杂交方法检测髁突软骨细胞内血管内皮生长因子及其受体Flt-1的表达,应用计算机图像分析系统计算阳性染色的灰度积分,应用SPSS10.0软件包进行配对q检验。结果：下颌外伤后双侧颞下颌关节髁突和关节盘均有不同程度损伤,髁突软骨增殖层和肥大层细胞胞质中检测到血管内皮生长因子及其受体Flt-1的表达,表达阳性强度随愈合时间而变化,各组阳性染色的灰度积分值差异具有统计学意义（P〈0.01）。结论：血管内皮生长因子及其受体Flt-1对颞下颌关节髁突损伤的修复起重要的生物学作用。     

不同方法处理大鼠髁颈部骨折对髁状突表层组织学的影响

本研究造成年幼大鼠髁颈部骨折，采用非固定及固定方法处理，观察对髁状突表层组织的长期影响．结果两种方法纤维层、增殖层及软骨细胞层细胞增殖均较活跃，后两层明显厚于对照组，但两种方法间无显著性差异．提示对年轻者髁颈部骨折可采取保守治疗．     

Condyle and mandibular bone change after unilateral condylar neck fracture in growing rats

Unilateral fracture of the condylar neck in immature subjects might lead to mandible asymmetry and condyle remodelling. A rat model was used to investigate mandibular deviation and condylar remodelling associated with condyle fracture. 72 4-week-old male rats were randomly divided into three groups: an experimental group (unilateral transverse condylar fracture induced surgically), a sham operation group (surgical exposure but no fracture), and a non-operative control group (no operation). The rats were killed at intervals up to 9weeks after surgery, and outcomes were assessed using various measures of mandible deviation, histological and X-ray observation, and immunohistochemical measures of expression levels of connective tissue growth factor (CTGF) and type II collagen (Col II). The fracture led to the degeneration of mandibular size, associated with atrophy of fractured condylar process. Progressive remodelling of cartilage and increasing expression levels of CTGF and Col II were found. The authors conclude that condylar fracture can lead to asymmetries in mandible and condyle remodelling and expression of CTGF and Col II in condylar cartilage on both the ipsilateral and the contralateral sides.     

髁突矢状骨折动物模型的实验研究

目的：建立髁突囊内矢状骨折动物模型,观察髁突骨折后不同时间的病理形态改变。方法：对10只绵羊进行实验,右侧关节为手术侧,从耳前区切开皮肤,到达颞下颌关节,切断关节盘前后附着,从髁突外侧嵴到内侧髁颈锯开髁突,建立斜形矢状骨折。髁突碎片和关节盘推向前下内侧,左侧关节为对照侧。分别于术后1周、4周和12周处死2只、4只和4只动物。记录术前和术后每组动物的体质量、最大开口度、侧方活动度,进行X线、CT和组织病理学观察。采用SPSS12.0软件包对数据进行统计分析。结果：各手术组体质量、左侧向活动度未发现显著差异,但是在4周和12周组中,最大开口度和右侧向活动度明显减小。在这2组中,X线检查发现髁突残端外侧有新骨生成,并向外侧生长,同时关节间隙变狭窄和模糊。三维CT检查发现,髁突残端、髁突碎片和关节结节均发生改建。组织病理学观察发现,在4周和12周组动物,关节腔充满纤维组织、软骨和骨组织。结论：该研究表明,此类骨折可以导致髁突骨关节病理改变,颞下颌关节有发展为关节强直的可能。     

A sheep model of intracapsular condylar fracture.

PURPOSE: An animal model of a condylar head fracture similar to a type B intracapsular fracture in humans was created. The effect of this model on mandibular function and morphological changes of temporomandibular joint (TMJ) structure was evaluated. MATERIALS AND METHODS: Ten sheep were divided into 3 groups, sacrificed at 1 week (2 sheep), 4 weeks (4 sheep), and 12 weeks (4 sheep) after surgery. The right side of the TMJ was considered the surgical group; the left side, the control group. The anterior and posterior attachments of the discs were cut, and an oblique vertical osteotomy was made from the lateral pole of the condyle to the medial side of the condylar neck. The condyle fragment was pushed together with the disc anteriorly, inferiorly, and medially. The lateral side of the condylar stump was sutured to the capsule to limit movement. Preoperative and postoperative body weight, maximum mouth opening, lateral excursions, and x-ray and computed tomography (CT) findings in the 3 surgical groups and the control group were recorded. The SPSS software program was used for all statistical analyses. RESULTS: There were no significant differences in weight loss and left lateral movement among the 3 surgical groups, but maximum mouth opening and the right lateral movement decreased significantly in the 4-week and 12-week surgical groups. X-rays demonstrated severe bone erosion and new bony outgrowth in the lateral side of the condylar stump and a narrowed, indistinct joint space in these 2 groups. Three-dimensional reconstruction of CT images showed changed contours of the condylar stump, condylar fragment and articular eminence in all 3 surgical groups. CONCLUSIONS: This study demonstrates progressive changes toward ankylosis and pathological changes in sheep TMJ over time consistent with what has been found in humans.     

羊髁突囊内骨折坚强内固定动物模型的建立

目的：创建羊髁突囊内B型骨折并同期行坚强内固定术的实验动物模型,观察髁突囊内骨折固定术后的愈合情况。方法：12只6个月龄山羊分为实验组和对照组,实验组8只,一侧关节手术造成髁突囊内B型骨折并用两孔钛板＋钢丝固定,对照组不作任何处理;术后3、6个月各处死6只,术后即刻及3、6个月行螺旋CT扫描,手术前和处死前测量实验动物的体重和最大开口度,采用SAS6.12软件包对数据进行Kruskal-Wallis检验。结果：实验组和对照组自身术后3、6个月体重和术前体重有统计学差异（P〈0.05）,但实验组和对照组之间的术前及术后3、6个月体重无统计学差异（P〉0.05）,实验组和对照组术前及术后3、6个月最大开口度自身比较和组间比较均无统计学差异（P〉0.05）;螺旋CT显示骨折固定良好,固位钉稳固,骨折愈合良好。结论：髁突囊内B型骨折后施行恰当的坚强内固定术,可以促进骨折愈合。     

翼外肌在髁突矢状骨折愈合过程中对髁突形态改建的影响

目的：本实验的目的是检查翼外肌在髁突矢状骨折愈合过程中,对髁突形态改建的影响。方法：20只1岁龄成年绵羊,随机分为两组,每组10只动物,所有绵羊都用超声骨刀造成髁突矢状骨折,剪断关节盘前后附着并将其推向内侧,其中组1动物切断翼外肌,组2动物保留翼外肌功能。每组动物分别在术后4周（各2只）、12周（各4只）、24周（各4只）处死。处死后行CT检查,CT三维重建观察髁突形态,并解剖颞颌关节（TMJ）以观察髁突形态。结果：组2即保留翼外肌功能组,较组1髁突有更多新骨形成,髁突形态改变更严重。结论：翼外肌在髁突矢状骨折愈合过程中对髁突形态改建的影响起非常重要的作用。     

Recovery of mandibular motion after closed and open treatment of unilateral mandibular condylar process fractures

The purpose of this study was to determine the rate of recovery of mandibular motion in patients treated for fractures of the mandibular condylar process. One hundred and thirty-six patients (111 men, 25 women), 74 treated by closed and 62 by open methods, were included. They underwent testing of mandibular and condyle mobility at 6 weeks, 6 months, and 1, 2, and 3 years post surgery. Their ranges of motion were compared to those of 52 controls (26 men and 26 women). A jaw-tracking device was used to assess mandibular motion. Multilevel statistical models were used to assess differences between groups, and to estimate rate of recovery in the fracture patients. In general, patients with unilateral fractures of the condylar process had maximum excursions that returned to normal values within 3 years after fracture, regardless of treatment. Patients treated open exhibited a faster rate of improvement in maximum interincisal opening than patients treated closed (0.43 mm/month vs 0.15 mm/month, respectively), but part of the difference was due to a significantly smaller opening after 6 weeks for the patients treated open (38 mm vs 42 mm, respectively). Patients treated open also exhibited a faster rate of improvement in maximum excursion toward the fracture side than patients treated closed (0.10 mm/month vs 0.04 mm/month, respectively). Based upon this study, patients with unilateral fractures of the condylar process, who are treated closed and not put into maxillomandibular fixation but are instructed in physical therapy, can be expected to achieve normal maximum excursions within 3 years after treatment. Patients treated open will have reduced maximum opening initially, but may reach normal levels of opening sooner than patients treated without surgery. Patients treated without surgery may have smaller than normal excursion toward the non-fracture side for at least 3 years after fracture, especially if their fracture was at or above the condylar neck. Improvement rates for other maximum excursions are similar for patients treated with or without surgery.     

Histological evaluation of condylar hyperplasia model of rabbit following distraction osteogenesis of the condylar neck

Summary Condylar hyperplasia is the excessive unilateral growth of mandibular leading to facial asymmetry, occlusal disturbance, joint pain and dysfunction. The aim of this study is to evaluate the histological presence of temporomandibular joint in model of condylar hyperplasia by lengthening unilateral condylar neck of distraction osteogenesis. An extra oral distractor was employed to achieve unilateral condylar neck distraction (1·0 mm daily for 7 days). The experimental condylar necks were elongated by 7 mm compared to the contralateral. Eleven adult white rabbits were used. Eight rabbits were, respectively, sacrificed after the post‐distraction period (4 or 8 weeks). All animals were evaluated clinically and histomorphometrically. The condyles radiologically showed remodelling, flattening and sclerosis. In 4‐week group, thinning of the cartilage was evident, and the trabeculae were long, not multiply connected. A thin, dense fibrous layer covered all over the surface of cartilage. In 8‐week group, the cartilaginous layer was similar to thickness of the normal cartilage, but still thinner than control. However, the fibrous layers covering condyle manifested slight degenerative changes, and even depressions and erosions were seen in the cartilage and subchondral bone. The trabeculae showed denser and multiply connected. In 8‐week group, the cartilaginous thickness of surgical condyles was significantly thinner than the contralateral. This study indicates that unilateral distraction of condylar neck loads the condyles asymmetrically. Asymmetrical loads affect more on the surgical condyles than the contralateral, and after 8 weeks of the post‐distraction, condyle could recover from asymmetrical loads in some degree.     

渐进性咬合紊乱对大鼠髁突软骨中骨形成蛋白2表达的影响

目的：探讨渐进性咬合紊乱所致大鼠髁突软骨改建中骨形成蛋白2（BMP-2）的变化情况及其意义。方法：建立幼年和成年大鼠渐进性咬合紊乱模型,应用免疫组化SABC法检测大鼠髁突软骨中BMP-2的表达变化,并作图像分析和统计学处理。结果：幼年和成年实验组大鼠左右侧髁突软骨中BMP-2的表达差异无统计学意义。与对照组相比,幼年和成年实验组中BMP-2的表达于实验4周时均低于对照组（P〈0.01）,之后出现回升,8周时两组均高于对照组（P〈0.05）。不同时间点比较,幼年与成年实验组中BMP-2的表达在2~8周的时间内均出现先降低再增高的趋势。结论：BMP-2参与了髁突软骨随咬合变化而发生的改建活动。     

Bite forces after open or closed treatment of mandibular condylar process fractures.

PURPOSE: This study compared maximum voluntary bite forces in patients who received either open or closed treatment for fractures of the mandibular condylar process. PATIENTS AND METHODS: One hundred fifty-five patients (127 male, 28 female) with unilateral fractures of the mandibular condylar process (91 treated closed and 64 treated open) were included in this study. Maximum voluntary bite forces were measured at 6 weeks, 6 months, and 1, 2, and 3 years after fracture. At each trial, unilateral maximum voluntary bite force was measured at 4 different tooth positions bilaterally using a standard transducer. Electromyography (EMG) of the masseter muscles was also recorded during the bite force measurements, and ratios of the working/balancing side EMG were calculated. Analysis of the data was performed using standard statistical methods. RESULTS: The only significant difference between the 2 samples was in the level of fractures on the condylar process. No patients treated open had fractures of the "head" of the condylar process, whereas there were 11 in the group treated closed. No differences were observed in maximum voluntary bite forces between the 2 treatment groups at any time period, or were there correlations between bite force magnitude and location of the fracture, displacement of the fracture, or any other variable studied. Both groups showed a significant recovery of maximum bite force from the 6-week to the 6-month testing session. For both groups, working/balancing EMG ratios were significantly greater when subjects were biting on the side opposite the fracture. When biting on that side, the working/balancing EMG ratios were higher in the closed treatment group, but the difference did not reach significance. CONCLUSIONS: Maximum voluntary bite forces in patients treated for mandibular condylar process fractures do not differ significantly when treatment is open or closed. Neuromuscular adaptations to the fractured mandibular condylar process occur in both groups.     

Condylar restoration after early TMJ fractures and functional appliance therapy

The aim of this study was to measure quantitatively and to analyze the process of condylar restoration during and after functional appliance therapy with an activator in children and juveniles who had sustained condylar fractures. Spiral computed measurement of condylar morphology was performed in order to quantify the association described in the literature between condylar remodelling and age as well as certain types of fracture. Nineteen patients with an average age of 13.4 years, who had sustained a functionally treated unilateral condylar fracture 4.9 years earlier on average, were included in the present study as the follow-up group. Twenty patients, who had sustained a unilateral fracture at an average age of 8.1 years and had been treated functionally for 6 to 8 months, formed the treatment group. The condylar dimension and the condylar neck length of the ipsilateral and of the contralateral temporomandibular joints were measured from the axial and parasagittal reconstructions and were compared on the basis of sex, age and fracture type. The mediolateral condylar dimension of the follow-up group showed a sex-specific difference of 0.2 cm on the contralateral side and 0.4 cm on the ipsilateral side. The fracture side condyle indicated a relative mediolateral decrease of 4.2% and an anteroposterior increase of 12.6%. Shortening of the condylar neck and excessive bony overgrowth were found to occur more often in fractures with displacement and in low fracture types. The 10-plus subgroup at time of trauma showed a significantly greater variation and greater differences in mediolateral and anteroposterior condylar dimension than the younger patients.