咀嚼力降低对发育期大鼠髁突发育的组织学影响

目的：探讨咀嚼力降低对断乳后大鼠下颌骨髁突尺寸和髁突软骨厚度的影响。方法：16只刚断乳的雄性大鼠随机分为两组。一组喂以标准的硬食,另一组以粉末状软食喂养。4w后,取每只大鼠的一侧髁突进行长度和宽度的测量,另一侧髁突进行组织学观察。结果：软食组大鼠的髁突长度、宽度和软骨层厚度均明显小于硬食组。结论：咀嚼力降低会导致下颌骨髁突生长减慢和髁突软骨厚度的变化。

Effect of low masticatory force on histomorphology of the mandibular condyle in growing rats

Objective: To estimate the effect of low masticatory force on the size of the mandibular condyle and the condylar cartilage thickness in rats soon after weaning. Methods: Sixteen 18 days old rats were randomly divided into 2 groups. One group received normal hard diet the other group received powder soft diet. The experimental period was 4 weeks. One condyle of each rat was used for gross morphometric analysis,the other condyle was used for histologic analysis. Results: The gross measurements made on the condyles show that both the length and width of condyle in soft diet group were significantly smaller than in the hard group. Significant difference was also found in the carilage thickness,soft diet group having a thinner carilage. Conclusion: Low masticatory force leads to decreased growth of the mandibular condyle and changes in the thickness of the carilage.