二层龋坏牙本质胶原蛋白中氨基酸含量测定及其临床意义

The determination of the Amino Acids in the collagenous proteins of two-layer carious dentin and its clinical values

目的 探讨牙本质龋损中胶原蛋白的变化特点 ,为临床牙本质龋的预防与治疗提供参考依据。方法 实验采用氨基酸自动分析仪测量正常和二层龋坏牙本质龋胶原蛋白中 1 8种氨基酸含量。结果 (1 )正常与内层龋坏牙本质胶原蛋白中 1 8种氨基酸含量无明显差别。 (2 )外层龋坏牙本质胶原蛋白除甘氨酸明显增高外 ,其余氨基酸含量明显低于正常及龋坏内层牙本质中的胶原蛋白。结论 说明牙本质发生龋损时 ,内层龋坏牙本质中的胶原蛋白 ,在其氨基酸含量及构成比方面无显著改变 ,同正常牙本质胶原蛋白 本质胶原蛋白一样为I型胶原 ;而外层龋坏牙本质中的胶原蛋白则发生了明显变化 。

Aim In order to provide the scientific basis for the prevention and treatment on dentinal caries, the changes of the collagenous proteins in carious dentin was investigated.Methods Eighteen a mino acid of the collagen in sound and two-layer carious dentin were determined by a Beckman 121 Amino Acid Analyzer.Results (1)There are no significant difference between the content of eighteen amino acids of collagen in sound and inter layer carious dentin.(2)In collagen of outer layer carious dentin,the content of Gly acid was much higher,the others were all lower than those of sound and inter layer carious dentin.Conclusion It was revealed that the collagen in inter layer of carious dentin,which didn’t change significantly in both content and compositional ratio of amino acid during dentinal lesion,was type I collagen same as that of sound dentin.However,the collagen in outer layer of carious dentin changed characteristically,was not type I collagen.