兔下颌骨髁突软骨年龄相关性改变的组织学研究

目的 探讨不同年龄段兔下颌骨髁突软骨的生理特征变化。方法 选取1、4、12和32周龄健康雌性新西兰大白兔各3只,脱钙处理后进行5 μm 连续切片,苏木精-伊红染色。分别对关节盘所覆盖的髁突表面纤维软骨区域软骨各层厚度进行测量分析。采用SPSS19.0软件包对数据进行统计学处理。结果 髁突软骨全层（P=0.008）、成熟层（P=0.008）和肥大层（P=0.007）在1周和4周组间厚度显著下降,在4~32周内厚度变化不明显。连续各组之间纤维层和增殖层厚度无显著改变;32周组纤维层厚度显著高于1周组（P=0.024）。结论 兔髁突软骨全层、成熟层和肥大层在1~4周内明显变薄,成骨活性大于成软骨活性,为下颌骨生长发育的重要阶段;在4~32周内各层厚度改变不明显,成骨和成软骨活性相对平衡。成年期髁突适应和耐受关节腔微环境变化的能力可能较强。

Age-related changes of mandibular condylar cartilage: A histomorphometric study in rabbit temporomandibular joint

PURPOSE: To study the age-related changes of the condylar cartilage in rabbit temporomandibular joint. METHODS: Three New Zealand rabbit were obtained at the ages of 1, 4, 12 and 32 weeks, respectively. Each specimen was subjected to histolgical assessment about each layer of fibrocartilage thickness. One-way ANOVA as performed using SPSS19.0 software package. RESULTS: The decrease of the total cartilage thickness (P=0.008), the mature layer (P=0.008) and the hypertrophic layer (P=0.007) occurred from 1 to 4 weeks, and there were no significant changes within 4-32 weeks. The changes of fibrous layer and proliferative layer thickness were not significant between 1-4 weeks, 4-12 weeks, 12-32 weeks. However, the thickness of fibrous layer was significantly greater at 32-week than at 1-week (P=0.024). CONCLUSIONS: The thickness of condylar cartilage, mature layer and hypertrophic layer decreased remarkably during 1-4 week. This period is the most important stage for mandibular in growth and development. The adulthood mandibular condyle might have a stronger adaptive capacity to alteration of pressure microenvironment in temporomandibular joint.