颞下颌关节盘前移位后髁突软骨细胞基质基因表达的变化

目的　探讨颞下颌关节盘前移位后髁突软骨细胞基质基因表达的变化。方法　建立40只大白兔颞下颌关节盘前移位动物模型,用地高辛标记cRNA探针原位杂交技术,检测术后不同病变时期髁突软骨细胞Ⅱ型胶原和蛋白多糖聚合体基因表达的改变。结果　正常髁突的增殖层深层、肥大层和钙化层细胞胞浆内可见大量Ⅱ型胶原和蛋白多糖聚合体mRNA表达。术后1周蛋白多糖聚合体开始下调,至2周达低谷,6周后恢复至正常水平。Ⅱ型胶原4周后开始持续下降,其表达下降程度较蛋白多糖聚合体显著,8周后逐渐恢复正常。结论　关节盘前移位后髁突软骨的基质基因表达发生有序、协调的变化,这种变化意味着适应性改建的启动。     

生长期兔颞下颌关节盘前移位对髁突软骨内Ihh和PTHrP表达的影响

目的：研究颞下颌关节盘前移位对生长期兔髁突软骨印度豪猪蛋白（Ihh）和甲状旁腺相关蛋白（PTHrP）表达的影响,探讨关节盘前移位与下颌骨髁突生长发育之间的关系。方法：取3个月龄日本大耳白兔21只．建立颞下颌关节盘前移位动物模型,分别于建模后4、8、12周处死取材,观察髁突软骨组织学变化,并通过免疫组织化学方法检测Ihh、PTHrP在髁突软骨中的表达与定位。结果：关节盘移位后4周,髁突软骨结构轻度紊乱;8周时,髁突前部软骨形态结构发生显著改变;12周时．软骨正常结构丧失进一步加剧。关节盘移位后4周,可见Ihh、PTHrP在增殖带深层细胞内明显表达,8周、12周时在髁突深层软骨细胞内表达。结论：颞下颌关节盘前移位导致髁突软骨结构进行性病理性损害．Ihh和PTHrP在盘移位后髁突软骨病理性改变的过程中发挥重要作用．提示关节盘前移位可能通过Ihh-PTHrP负反馈信号通路对生长期髁突软骨内成骨过程产生影响。     

髁状突矢状骨折类型与关节盘位移的关系

目的探讨下颌骨髁状突矢状骨折后骨折类型与关节盘位移情况的关系。方法通过计算机体层摄影术(CT)确诊下颌骨髁状突矢状骨折(A、B、C型)患者74例74侧,进行颞下颌关节磁共振成像(MRI)检查,明确关节盘移位情况,利用卡方检验分析不同骨折类型与关节盘移位的关系。结果 74例髁状突矢状骨折(A、B、C型)病例中,26例A型骨折中颞下颌关节盘不可复性前移位较多(57.69%);24例B型骨折中关节盘可复性前移位较多(62.5%);24例C型骨折中正常髁盘关系较多(50%)。不同骨折分型与髁盘关系间的差异有统计学意义(χ2=29.555,P=0.000)。结论下颌骨髁状突发生矢状骨折后,大部分病例中的关节盘出现相应位移,位移情况则与矢状骨折类型相关。关节盘移位以前移位为主,受伤程度越大越容易发生不可复性前移位。     

颞下颌关节盘移位患者髁突运动轨迹分析

目的:记录颞下颌关节盘移位患者和正常人下颌运动时髁突运动轨迹,分析关节盘移位对髁突运动的影响.方法:选取双侧不可复性关节盘移位(DDwoR)和可复性关节盘移位(DDwR)患者各18例,健康对照(HC)10例.电子髁突运动轨迹描记仪记录受试者下颌开闭口、前伸后退时髁突铰链轴运动轨迹,计算髁突最大位移(Smax)、髁突位移...     

急性和慢性不可复性盘前移位临床对比研究

目的　探讨颞下颌关节紊乱病不可复性盘前移位急性和慢性分类对临床诊断、治疗和预后的指导意义。方法　分析连续接诊的 10 0例不可复性盘前移位病例 (急性 4 5例、慢性 5 5例 ) ,比较两组之间临床主诉、开口度、颞下颌关节功能、髁突和关节盘的影像学改变。结果　急性不可复性盘前移位主诉开口受限 ,下颌运动功能严重障碍 ,大部分病例髁突骨质正常 ,关节盘形态良好 ;慢性不可复性盘前移位主诉多为开口痛和 (或 )咀嚼痛 ,下颌运动受限 ,部分病例伴有咀嚼肌疼痛 ,相当一部分病例髁突骨质吸收破坏 ,关节盘变形、变性 ,关节盘附着松弛、撕裂 ,甚至关节盘穿孔。结论　对急性不可复性盘前移位应早期采取积极的治疗 ,恢复良好的盘 突关系 ,阻止关节盘和髁突的进一步损伤。     

颞下颌关节盘前移位后VEGF-C基因在髁突软骨中的表达及意义

目的:探讨血管内皮细胞生长因子C在颞下颌关节盘前移位后髁突软骨中的表达及意义.方法:采用日本大耳白兔60只,48只用弹力丝牵拉关节盘前移,建立关节盘前移模型,分别于术后1、2、4、8周处死12只,12只空白对照组同期处死,取出颞下颌关节标本.利用基因芯片技术进行筛选,实时荧光定量PCR进行验证和SP免疫组化技术检测不同组内髁突软骨中VGEF-C的表达与分布.采用SPSS19.0软件包对每组样本实验组和对照组数据进行配对t检验.结果:颞下颌关节盘前移位后,在基因水平上VEGF-C相比于正常对照组均有不同程度变化,早期VEGF-C表达减少,第2周时降至最低水平,差异显著(P＜0.05);第8周时,VEGF-C表达有所增加.镜下观察可见VEGF-C在髁突软骨增殖层、肥大层及钙化软骨层中均有表达,1周组阳性表达主要见于增殖深层和肥大层,钙化软骨层也有弱阳性表达.2周组和4周组阳性表达主要位于肥大层,且在钙化软骨层中表达逐渐增强.8周组肥大层有阳性表达,钙化软骨层未见明显阳性表达,8周组与对照组相比有显著差异(P＜0.05).结论:关节盘前移位后早期髁突软骨VEGF-C基因的转录与表达有所下降,而在后期升高,可能参与关节盘移位后髁突软骨的改建.     

青少年单侧颞下颌关节盘不可复性前移位对髁突高度的影响

目的 基于磁共振测量,研究青少年单侧颞下颌关节盘不可复性前移位对髁突高度的影响。方法 选择2010年1月—2013年6月就诊并行随访观察的单侧颞下颌关节盘不可复性前移位青少年患者124例,平均年龄16岁,平均随访时间13.6个月。在磁共振片上测量髁突高度、盘长度及盘移位距离,比较健、患侧以及随访前、后的差异。采用SAS 9.13软件包对所得数据进行统计学分析。结果 患侧关节盘移位距离从5.44 mm增大至6.83 mm（P<0.05）;患侧关节盘长度从9.06 mm缩短为8.12 mm（P<0.05）;健侧髁突高度从26.07 mm增加至26.82 mm（P<0.05）;患侧髁突高度从24.22 mm降低为23.81 mm（P<0.05）;健、患侧髁突高度差异从1.85 mm扩大为3.00 mm（P<0.05）。结论 在青少年单侧颞下颌关节盘不可复性前移位患者病程中,患侧器质性病变继续进展,可能是单侧关节盘移位患者发生下颌偏斜的主要原因。     

兔颞下颌关节盘前移位后凋亡调控信号Bcl-2及Bax在髁突软骨细胞表达的研究

目的:研究颞下颌关节盘前移位后凋亡调控基因bcl-2及bax在髁突软骨细胞表达的变化.方法:17只日本大白兔随机分组,实验组行右侧颞下颌关节手术,人工造成颞下颌关节盘前移位,分别经1、2、4周后处死动物,Western blot检测侧髁突软骨bcl-2及bax表达.结果:实验组较对照组bax蛋白含量增加,且随着术后时间的延长而增加.bcl-2蛋白则相反,实验组较对照组动物关节软骨内表达减少,且随着术后时间的延长而进一步递减.结论:在颞下颌关节盘前移位后软骨凋亡过程中bcl-2/bax可能起一定调控作用.     

透明质酸钠注射治疗不可复性关节盘前移位的CBCT影像学评价

目的:对比治疗前后CBCT影像,观察透明质酸钠治疗颞下颌关节不可复性盘前移位后髁突位置及形态变化.方法:对40例患者进行3次透明质酸钠关节上腔注射治疗.通过治疗前、治疗后3、9、12个月CBCT影像学检查及临床检查,从髁突位置形态变化、疼痛度(VAS)、最大开口度(MMO)、Fricton指数观察透明质酸钠对颞下颌关节不可复性关节盘前移位的治疗效果.结果:CBCT显示不可复性关节盘前移位伴骨关节病患者治疗前与治疗后9、12个月比较,髁突骨质有明显改建,骨面变得平整光滑,骨赘减小(P =0.026,P=0.001),部分单纯不可复性关节盘前移位患者治疗后9个月髁突可以向前移动(P=0.038);治疗后患者MMO增大,VAS减小(P＜0.05),Fricton指数降低.治疗后3～12个月Fricton指数无显著变化(P＞0.05).结论:CBCT显示透明质酸钠可促进已破坏髁突表面骨质改建,但不能使后移位的髁突回到关节窝中央.     

锥形束CT颞下颌关节上腔造影在诊断关节盘病变中的应用

目的探讨颞下颌关节（TMJ）骨关节病中关节盘前移位、穿孔及髁突骨质改变类型的关系。 方法选择中山大学附属口腔医院颞下颌关节专科就诊的96例骨关节病患者共145侧TMJ行锥形束CT（CBCT）关节造影检查,分为关节盘穿孔组和非穿孔组,两组病例以CBCT按照关节盘移位及髁突骨质改变类型进行分类比较,应用SPSS 18.0对关节盘穿孔与关节盘移位类型进行Pearson χ²独立性检验,两组间骨质分型构成比进行χ²检验。 结果所有关节发生关节盘前移位,其中123侧为不可复性盘前移位、22侧为可复性盘前移位。86侧TMJ发生关节盘穿孔,59侧关节造影未检出穿孔。关节盘是否发生穿孔与关节盘前移位类型存在相关性（χ²= 6.866,P= 0.015）,关节盘穿孔组不可复性盘前移位发生率（91.86%）高于非关节盘穿孔组（76.3%）。 结论TMJ骨关节病患者均存在不同程度的关节盘移位,关节盘移位类型与关节盘穿孔相关,髁突骨质改变类型与关节盘是否穿孔无明显相关性。     

Forward deviation of the mandibular condyle enhances endochondral ossification of condylar cartilage indicated by increased expression of type X collagen

OBJECTIVE: Using type X collagen as a marker, this research was designed to examine the alteration of condylar growth in response to mandibular condylar forward positioning. METHODS: One hundred female Sprague-Dawley rats with 5 weeks of age were randomly divided into five experimental and five control groups. In the experimental groups, bite jumping appliances created forward positioning of the condyle. The experimental rats, together with the age-matched controls, were sacrificed on days 3, 7, 14, 21 and 30, respectively. Tissue sections were cut in the sagittal plane through the mandibular condyle and were processed for in situ hybridization and immunostaining of type X collagen and then for quantitative imaging analyses. RESULTS: (1) Both type X collagen mRNA in situ hybridization signals and type X collagen immunostaining were localized within the hypertrophic zone of the condylar cartilage. (2) With condylar forward positioning, the level of type X collagen mRNA signals (8,541 +/- 74 microm(2) at peak) was 300% higher than that in the controls (2,117 +/- 78 microm(2) at peak); type X collagen immunostaining in condylar advancing groups (54,864 +/- 134 microm(2) at peak) was 254% more than that in the controls (15,470 +/- 121 microm(2) at peak). (3) The amount of type X collagen mRNA signals and immunostaining in experimental and control groups reached the highest levels at day 14 and day 21, respectively, indicating that an increase in endochondral ossification occurred 21 days after condylar forward deviation. CONCLUSION: Condylar forward repositioning provokes an enhanced maturation of condylar chondrocytes resulting in increased synthesis of type X collagen, a extracellular protein that attributes to endochondral ossification.     

Expression of type X collagen and capillary endothelium in condylar cartilage during osteogenic transition--a comparison between adaptive remodelling and natural growth

Adaptive remodelling of the condylar cartilage in response to mandibular protrusion constitutes the rationale for bite-jumping appliances to solicit growth modification. By investigating the expression of type X collagen and capillary endothelium, this study was designed to evaluate the osteogenic transition of chondrogenesis during adaptive remodelling of condylar cartilage and compare it with that under natural condylar growth. One hundred female Sprague-Dawley rats, 35 days of age, were divided into five experimental groups (n = 15, fitted with bite-jumping appliances) where condylar adaptation was created by forward repositioning of the mandible, and five control groups (n = 5) where the condyles underwent natural growth. The animals were sacrificed at 3, 7, 14, 21 and 30 days and 7 mum serial sections of the condyles were processed for in situ hybridization and immunohistochemical analyses. The expression of type X collagen in the hypertrophic zone and capillary endothelium in the erosive zone of condylar cartilage were examined to evaluate osteogenic transition, a critical programme leading to endochondral ossification. The results showed that (1) The temporal pattern of the expression of type X collagen and capillary endothelium during condylar adaptation coincided with that during natural condylar growth. (2) The amount of the expression of these two factors during condylar adaptation was significantly higher than that during natural growth (P < 0.001). It is suggested that condylar adaptation in growing rats triggered by mandibular forward positioning enhances osteogenic transition which eventually results in increased bone formation.     

The role of type X collagen in facilitating and regulating endochondral ossification of articular cartilage

AUTHOR: Shen G Objective -This review was compiled to explore the role of type X collagen in growth, development and remodeling of articular cartilage by elucidating the linkage between the synthesis of this protein and the phenotypic changes in chondrogenesis and the onset of endochondral ossification. DESIGN: The current studies closely dedicated to elucidating the role of type X collagen incorporating into chondrogenesis and endochondral ossification of articular cartilage were assessed and analyzed to allow for obtaining the mainstream consensus on the bio-molecular mechanism with which type X collagen functions in articular cartilage. RESULTS: There are spatial and temporal correlations between synthesis of type X collagen and occurrence of endochondral ossification. The expression of type X collagen is confined within hypertrophic condrocytes and precedes the embark of endochondral bone formation. Type X collagen facilitates endochondral ossification by regulating matrix mineralization and compartmentalizing matrix components. CONCLUSION: Type X collagen is a reliable marker for new bone formation in articular cartilage. The future clinical application of this collagen in inducing or mediating endochondral ossification is perceived, e.g. the fracture healing of synovial joints and adaptive remodeling of madibular condyle.     

应用数学模型观察BMPs对幼鼠髁突颈骨折愈合的影响

目的:利用骨形成蛋白(BMPs)家族不同代谢条件数学模型,研究BMPs家族不同代谢条件对幼鼠髁突颈骨折愈合的影响。方法:构建BMPs家族不同代谢条件的数学模型,通过模型中BMPs家族细胞因子分泌速度常数(Ggb)和BMPs家族细胞因子降解半衰期常数(dgb)的梯度变化,观察骨折后28d内骨折断端骨桥形成时间、颊侧骨痂完全骨化时间、骨组织平均密度、骨生长曲线和成骨方式。结果:该模型所显示的常数Ggb降低,可明显抑制软骨内成骨过程,延长颊侧骨痂的完全骨化时间,但骨桥形成时间无明显改变;常数dgb升高,可延长颊侧骨痂完全骨化和骨桥形成时间,无软骨内成骨过程。结论:该模型可观察到BMPs家族细胞因子有促进幼鼠髁突颈骨折愈合的作用,为临床治疗提供参考依据。     

Endochondral ossification of the condyle in rats on a strontium or low-calcium diet

The mechanism of abnormal endochondral ossification induced by administration of strontium salts was studied in the mandibular condyles of rats by radiographic, histologic, and histochemical methods. It was shown by radiographic and histologic findings that ossification of the mandibular ramus was clearly inhibited in rats fed a low-calcium diet and rats fed a strontium diet. The change in appearance of the mandibular condyles of the rats fed strontium was more severe than that in those fed low amounts of calcium. From the histochemical findings, it was suggested that the metabolic dysfunction of chondroitin sulfate, periodic acid-Schiff positive materials, and collagen in the hypertrophic zone of the condylar cartilage (or in the part corresponding to trabecular bone of the mandibular ramus) was one factor inhibiting normal endochondral ossification.     

Identification of temporal pattern of mandibular condylar growth: a molecular and biochemical experiment

OBJECTIVES: Based on the phenomenon that expression of type X collagen and capillary endothelium correlates with endochondral ossification, the prime aim of this study was to establish the temporal pattern of condylar growth in Sprague-Dawley rats by biochemically identifying the expression of these two factors. DESIGN: Sprague-Dawley rats were divided into five groups representing five different stages during somatic pubertal growth. In situ hybridization and immunoperoxidase were performed to examine expression of type X collagen in hypertrophic zone and capillary endothelium in erosive zone of condylar cartilage. Computer-assisted imaging analyses were conducted to allow for a quantitative assessment of the expression of these two factors, from which the temporal pattern of condylar growth was inferred. RESULTS: (1) Synthesis of type X collagen and emergence of capillary endothelium were critical factors during the transition of condylar cartilage from chondrogenesis into osteogenesis, a biological pathway that leads to endochondral bone formation, the mode through which the condyle grows. (2) Quantitative analyses revealed the temporal pattern of the expression of these two factors, indicating that the thrust of natural growth of the condyle in the rats occurred in concomitance with somatic pubertal growth, featured by an acceleration starting from day 38, a maximum growth rate on day 56, followed by a decrease afterwards. CONCLUSION: It is suggested that the biochemical examination of growth markers, such as type X collagen, might be a new approach to accurately depict temporal pattern of condylar growth which is too delicate to be reflected by gross measurement not only in Sprague-Dawley rats but potentially also in other species.     

下颌前伸后髁突软骨成熟层内X型胶原的表达

目的：检测下颌骨前伸条件下,大鼠髁突内Ｘ型胶原的表达,从而论证髁突新骨的形成状况。方法：１００只同源雌性大鼠５组实验组及５组对照组,实验组动物戴用统一规格的咬合前导矫正器,各实验组及相应对照组动物分别在实验的第３、７、１４、２１及３０ｄ处死。应用分子原位杂交及免疫组织化学技术对髁突软骨成熟慨内的Ｘ型胶原ｍＲＮＡ及其蛋白的表达进行评价。结果：实验组,特别是２１ｄ组动物其髁突软骨成熟层细胞内有强烈的Ｍ     

Ⅰ、Ⅱ、Ⅹ型胶原及碱性磷酸酶在鼠胚髁突软骨发生中的意义

目的　探讨髁突软骨发生中Ⅰ、Ⅱ、Ⅹ型胶原及碱性磷酸酶(ALP)的组织学分布特征及髁突软骨内成骨的 分子机制。方法　取14~18 d鼠胚,分别行Ⅰ、Ⅱ、Ⅹ型胶原及ALP抗体免疫组织化学染色。结果　胚胎第14天, 髁突形成的位置可见间充质细胞聚集并与骨膜相连,间充质细胞及骨膜中Ⅰ型胶原及ALP阳性;第15天,肥大软 骨细胞中Ⅹ型胶原表达阳性,其周围的间充质细胞中Ⅰ、Ⅱ型胶原阳性,ALP在两种细胞中均呈阳性;第16天,软骨 膜、纤维层间充质细胞至肥大软骨细胞上层中Ⅰ型胶原表达阳性,多形细胞层下方至肥大软骨细胞下层中Ⅱ型胶 原表达阳性,Ⅹ型胶原仅表达于肥大软骨细胞,ALP在软骨膜及肥大软骨细胞中呈阳性,但在多形细胞层呈阴性或 弱阳性。结论　髁突软骨的发生机制与长骨不同,其软骨内成骨的早期Ⅰ、Ⅱ、Ⅹ型胶原均有表达,可能始发于ALP 阳性的下颌骨膜间充质细胞。