咬合力增强对老年大鼠磨牙牙周组织成骨和增殖细胞核抗原表达的影响

目的研究咬合力增强对老年大鼠牙周组织成骨和增殖细胞核抗原(PCNA)表达的影响。方法建立咬合力增强动物模型,运用伊红(HE)染色、碱性磷酸酶(ALP)染色、抗酒石酸酸性磷酸酶(TRAP)染色和PCNA免疫组织化学染色检测牙周组织成骨和PCNA表达的变化。结果咬合力增强2周时牙周膜结构致密,牙槽骨骨壁凹凸不平,同时可见交替出现的骨形成区;4周时牙周膜细胞PCNA阳性率最高,6周时牙槽骨表面成骨细胞的ALP染色强阳性,成骨活跃;而各组破骨细胞数目无显著差异。结论老年大鼠的牙周支持组织能在一定范围内耐受高于生理状态的咬合力,为临床上老年患者制作固定义齿提供了理论依据。

Effect of increased bite force on osteogenisis and expression of proliferating cell nuclear antigen in aged rat molar periodontium

Objective To observe the effect of increased bite force on the osteogenisis and expression of proliferating cell nuclear antigen(PCNA) in the aged rat molar periodontium.Methods Animal models were established by extracting the left maxillary molars.The staining of HE,ALP and TRAP and the immunohistochemical staining of PCNA were applied to examine the osteogenisis and expression of PCNA in the periodontal tissue.Results The periodontal membranes were tighter for the 2w group,with accidented alveolar bone proper surface and alternant bone formation region;the expression of PCNA of periodontal membrane cell was the highest for the 4w group;the expression of ALP of osteoblast was the highest for the 6w group.There was no significant difference within each group of the number in osteoclast.Conclusions Periodontal tissue can support the bite force that is larger than physiological bite force to a certain extent,which can provide the theorectical support for the aged patients in clinic.