I型胶原纤维降解对牙本质粘接耐久性的影响

目的：评价Ⅰ型胶原纤维降解对牙本质粘接耐久性的影响。方法不同粘接系统牙本质试件浸泡于去离子水或人工唾液中24 h、1个月、4个月，以酶联免疫吸附试验定量测定浸提液中Ⅰ型胶原吡啶交联终肽（ICTP）含量，以此衡量Ⅰ型胶原的降解程度，继以万能材料试验机测试微拉伸粘接强度后，以Pearson相关系数分析微拉伸粘接强度与ICTP 释放量之间的相关性。结果3种牙本质粘接系统，随着人工唾液浸泡时间的增长，其粘接强度均有所下降，而各组的胶原降解ICTP释放量均随之增高。ICTP释放量及微拉伸粘接强度数据的散点图决定系数R2＝0.75，表明胶原降解后ICTP释放量与粘接强度值之间具有高度相关性。结论Ⅰ型胶原降解后ICTP释放量与牙本质粘接强度值之间呈负相关关系，牙本质粘接强度值随Ⅰ型胶原降解后 ICTP 释放量的增加而下降，说明Ⅰ型胶原的降解对牙本质粘接耐久性产生了不利影响。

Effects of type I collagen degradation on the durability of dentin bonding

Objective This study was designed to evaluate the effects of typeⅠcollagen degradation on the durability of dentin bonding. Methods 3 groups of dentin specimens three different types of adhesive systems were immersed into deionized water or artificial saliva solution for 24 h, 1 m, 4 m. Cross-linked carboxyterminal telopeptide of typeⅠcollagen （ICTP） concentrations were then calculated by enzyme linked immunosorbent assay, in order to determine the degradation of typeⅠcollagen. Micro-tensile bond strength were tested before, and after 1 month or 4 months of aging in artificial saliva solution. The relationship between micro-tensile bond strength and collagen degradation was analyzed by conducting their Pearson＇s correlation coefficient. Results Prolonged artificial saliva solution immersion time led to decreasing of the bond strength as well as increasing of the quantity of ICTP of all 3 groups adhesive systems. The high correlation was discovered between the quantity of ICTP and the microtensile bond strength of dentin adhesion（R2=0.75）. Conclusions When typeⅠcollagen degradates, the relationship between the quantity of released ICTP and the microtensile bond strength of dentin adhesion turns out to be negative correlation, which means degradation of typeⅠcollagen exerts a negative effect on dentin adhesion bond durability.