CAJ | 학술논문

目的建立年轻SD大鼠单侧髁突颈部截骨、骨折的动物模型,探讨应力改变对大鼠下颌骨及髁突生长发育的影响.方法 4周龄72只雄性SD大鼠按随机数字表法分3组,每组24只,分为截骨组、骨折组、对照组.建立大鼠单侧髁突颈部横行截骨,骨折的动物模型,观察术后1、3、5、9周髁突影像学、组织学及下颌骨解剖学的变化.检测与髁突生长发育关系密切的结缔组织生长因子(CTGF)及X型胶原(Col X)在髁突软骨中表达的变化.结果截骨组手术侧术后1、3周髁突区膨大,髁突颈呈分离影像.骨折组手术侧术后1周髁突呈圆柱状,见骨折线.截骨组手术侧术后4个时间点下颌骨生长发育受到限制,髁突软骨的总厚度术后1周代偿性增厚为(1468.28±53.73) μm,大于骨折组手术侧;术后3、5周总厚度明显降低;术后9周与骨折组手术侧比较差异无统计学意义(P＞0.05),但都小于对照组(P＜0.05).截骨组手术侧CTGF在髁突软骨中的表达在术后1、3、5周分别为60.18±1.23、72.43±2.82、86.00±2.90均高于骨折组手术侧和对照组Col X表达在术后1周时为64.46±3.76,高于骨折组手术侧和对照组(均为P＜0.05).结论单侧髁突颈截骨,致应力改变明显,影响下颌骨及髁突生长发育,可导致手术侧、非手术侧下颌骨的不对称,并影响CTGF及Col X在髁突软骨的表达.
목적 건립년경SD대서단측과돌경부절골、골절적동물모형,탐토응력개변대대서하합골급과돌생장발육적영향.방법 4주령72지웅성SD대서안수궤수자표법분3조,매조24지,분위절골조、골절조、대조조.건립대서단측과돌경부횡행절골,골절적동물모형,관찰술후1、3、5、9주과돌영상학、조직학급하합골해부학적변화.검측여과돌생장발육관계밀절적결체조직생장인자(CTGF)급X형효원(Col X)재과돌연골중표체적변화.결과 절골조수술측술후1、3주과돌구팽대,과돌경정분리영상.골절조수술측술후1주과돌정원주상,견골절선.절골조수술측술후4개시간점하합골생장발육수도한제,과돌연골적총후도술후1주대상성증후위(1468.28±53.73) μm,대우골절조수술측;술후3、5주총후도명현강저;술후9주여골절조수술측비교차이무통계학의의(P＞0.05),단도소우대조조(P＜0.05).절골조수술측CTGF재과돌연골중적표체재술후1、3、5주분별위60.18±1.23、72.43±2.82、86.00±2.90균고우골절조수술측화대조조Col X표체재술후1주시위64.46±3.76,고우골절조수술측화대조조(균위P＜0.05).결론 단측과돌경절골,치응력개변명현,영향하합골급과돌생장발육,가도치수술측、비수술측하합골적불대칭,병영향CTGF급Col X재과돌연골적표체.
Objective To establish the condylar neck osteotomy or fracture rat model,and to determine the effects of stress changes on the growth and development of mandible.Methods Seventy-two SD rats of 4 weeks age were randomly assigned to unilateral condylar process osteotomy group (n=24),fracture group (n=24) and Sham operation group (n=24).Following construction of the models of unilateral condylar process osteotomy,the imaging characteristics,histological and anatomical changes were recorded at 1,3,5 and 9 weeks.Expressions of development-associated connective tissue growth factor (CTGF) and type X collagen (Col X) were assayed by immunohistochemical staining.Results The condyle on the operated side was enlarged and the neck separated on imaging at weeks 1 and 3 in unilateral condylar process osteotomy group.However,in fracture group,the condyle appeared to be cylindrical,which demonstrated the fracture line at week 1.Unilateral condylar process osteotomy was associated with retarded growth and development of mandible in the operated side at weeks 1,3,5 and 9.The thickness of condylar cartilage enlarged compensatorily to (1468.28±53.73) μtm at week 1 compared with that in fracture group (P＜0.05).This was followed by a gradual decline in the thickness at weeks 3 and 5 that was not statistically different from that in fracture group at week 9 (P＞0.05).Both groups yielded a reduced level of thickness compared with Sham operation group (all P＜0.05).The CTGF expression at the operated side in unilateral condylar process osteotomy group was 60.18±1.23,72.43±2.82 and 86.00±2.90 at weeks 1,3 and 5,respectively,which were higher compared with those in fracture group and Sham operation group (all P＜0.05).At week 1,Col X expression (64.46±3.76) was significantly augmented compared with that in fracture group and Sham operation group (both P＜0.05).Conclusion Unilateral condylar process osteotomy may result in asymmetry of the mandible at operated and non-operated side as well as altered expression of CTGF and Col X in the condyle chondria,which arises from significantly altered stress and retarded development of the mandible and condyle.