Effect of elastic behavior of the hybrid layer on dentin bonding stability

混合层弹性行为对牙本质粘结稳定性的影响

• 批准号: 09470417
• 负责人: UNO Shigeru
• 金额: $ 4.35万
• 依托单位: HOKKAIDO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09470417/
• 关键词: resin composite; dentin adhesion; hybrid layer; contraction shrinkage; elasticity

The effect of elastic properties of the hybrid zone on the dentin bonding efficacy was investigated in four commercialized adhesive systems.Evaluation of the elastic properties of the bonding area : Polished coronal dentin surface of human extracted molars were subjected to the study. Three brands of wet bonding system and a set-etching primer system were used in the study. The elastic properties was calculated from the difference. Between the total indentation depth after 10 gf loading for 30 seconds and permanent indentation depth after removal of the load measured by means of a universal microhardness testing machine. Indentation test was performed on the surfaces of polished dentin, etched/primed dentin, bonding resin applied and resin composite.Cavity adaptation in the dentinal cavity : On the flat coronal dentin, a cylindrical cavity 3.5 mm in diameter and 2 mm in depth, was prepared. After restored with the above restorative systems, the restoration was sectioned. Cavity adaptation was evaluated on the section along the cavity wall under a light microscope.Results and Discussion : Across the bonding area from the untreated dentin to resin composite, a drastic reduction of the elasticity was found at the bonding resin layer in the three wet bonding systems, while a self-etching primer system showed a gradient of the elastic properties. Concerning cavity adaptation. gap formation caused by the contraction stresses was seen at the line angle and/or cavity floor in the. wet bonding systems. A self-etching primer system resulted in a good sealing along the cavity wall. These results implied that. the hybrid layer might play a role of stress-releasing. The stress-releasing by the hybrid layer may be effective when the bonding area is graded in terms of elasticity and not related with the dimension of the hybridization.

在四种商品化的粘接系统中，研究了混合区的弹性特性对牙本质粘接效果的影响。粘结区的弹性特性的评估：以人拔除磨牙的抛光冠状牙本质表面为研究对象。研究中使用了三种品牌的湿式粘接系统和一种蚀刻底漆系统。根据差值计算出材料的弹性性能。通过万能显微硬度计测量，加载10gf 30秒后的总压痕深度与卸载载荷后的永久压痕深度之间的差异。对抛光牙本质、酸蚀/预涂处理牙本质、粘结树脂和树脂复合体的表面进行压痕试验。牙本质腔内的空洞适合性：在平顶冠牙本质上，形成直径3.5 mm、深度2 mm的圆柱形洞。用上述修复系统修复后，对修复体进行切开。结果与讨论：三种湿式粘接系统的粘接树脂层弹性均显著降低，而自酸蚀底漆粘接系统的弹性性能出现梯度变化。关于空洞适应。由收缩应力引起的缝隙形成在线角和/或空洞底部。湿法粘合系统。自酸蚀底漆系统使洞壁具有良好的密封性。这些结果表明。杂化层可能起到释放压力的作用。当粘结区按弹性分级时，杂化层的应力释放可能是有效的，而与杂化的尺寸无关。