人牙根龋发生中有机质破坏的酶学研究

目的 :了解牙根部有机质破坏的机制。方法 :将健康恒牙根颈 1/ 3牙体硬组织 ,磨制成 38.5～149m组织粉粒作样本 ,乳酸 (p H 4.0和 p H5 .5 )及醋酸 (p H 4.5和 p H5 .5 )溶液预处理后 ,测定钙、总蛋白和胶原含量 ;再经胰酶、胶原酶处理后分析释出的胶原量。结果 :乳酸和醋酸预处理不能降解人牙根部的胶原 ,但采用 p H4.0的乳酸处理牙齿后可以使酶对牙本质胶原的降解量明显增高 ,达 (4 4.0 5± 4.5 0 ) μl/ mg;随 p H升高 ,胰酶和胶原酶对根部牙体组织胶原的降解量明显下降 ,脱矿程度减弱 ,钙释出减少。结论 :酸和酶有协同降解胶原的作用。

STUDY OF THE DESTRUCTION OF ORGANIC COMPONENTS OF DENTAL ROOT

Objective:To comprehend the destructive mechanism of organic components of human dental toot Methods: Milled the cervical one-third of humandental root into powder as sample At firstly,the powder was pretreated with lactic acid (pH4 0 and pH5 5)and acetic acid(pH4 5 and pH5 5), determinated the release of Ca 2+ ,total protein and collagen Then it was treated with trypsin and collagenase,and determinated the release of collagen Results: Lactic acid and acetic acid almost had no effect on the degradation of the collagen of dental root alone But pretreatment of lactic acid(pH4 0) increased apparently the degradationof collagen by trhpsin and collagenase Conclusion: Acid and enzyme have cooperativity in the degradation of collagen