咬合力增强和减弱对大鼠磨牙牙周支持组织形态学的影响

目的　研究咬合力对牙周组织形态学的影响。方法　用拔牙法建立大鼠咬合力增强和减弱的动物模型 ,并用显微标尺测量牙周膜宽度及牙骨质厚度的动态变化。结果　在成模 1周后 ,咬合力减弱组牙周组织形态发生明显变化 ,而咬合力增强组未见明显变化。在成模 2周及 3周后 ,咬合力减弱组及咬合力增强组的牙周膜宽度与对照组间有显著差异 ( P<0 .0 5 ) ,并且其牙骨质厚度近、远、中侧间有显著性差异 ( P <0 .0 5 )。结论　牙周膜组织形态与受力密切相关 ,在生理条件下的咬合力对维持牙周膜的正常结构具有重要意义

Effect of Increased and Decreased Bite Force on Morphology of Periodontal Tissues

Objective The aim of this study was to observe th e effect of bite force o n morphology of periodontal tissues.Methods Animal models were induced by extracting th e left maxillary molars; the left mandibular molars served as decreased bite for ce models; the right mandibular molars served as increased bite force models. Th e dynamic changes of widths of periodontal ligament and cementum were measured. Results In decreased bite force group, there were significant m orphologic changes of per iodontal tissues after 1 week. In increased bite force group, there was no signi ficant change. Ligament widths were significantly different after 2,3 weeks resp ectively in those two groups, compared with that in control group ( P <0.05). There were significant differences between proximal alveolar wall and distal alveolar wall in width( P <0.05). Conclusion The histological morphol ogy is closely related to the me chanical condition. Physiological bite force is necessary for periodontal ligame nt to maintain its physiological structure.