Development of New Dental Adhesives

牙本质黏附是黏附牙科的一项关键技术，但目前仍未得到很好的认可。通过结合强度、结合试样的SEM和TEM分析，探讨了结合机理。在牙本质侧粘接剂界面形成杂化层是树脂与牙本质结合的关键。混合层不是牙本质，也不是树脂，而是牙本质和固化树脂的混合物。它是由分散的和浸渍的单体在牙本质中聚合形成的。单体扩散速率是单体扩散率和渗透牙本质扩散率的函数。具有疏水和亲水基团的单体可以促进单体向底物的扩散。各种以甲基丙烯酸酯为基础的材料已被开发出来，具有粘附牙本质的能力。在这个项目中，2-（甲基丙烯酰氧基）乙基苯基磷酸氢（phenyl- p）将甲基丙烯酸甲酯中5%的苯基p键合到牙本质表面的有效性。采用部分氧化的三正丁基硼烷催化剂（TBB）引发了苯基p /MMA单体的聚合反应。用10%柠檬酸/3%氯化铁水溶液预处理的MMA中5%苯基p与牙本质的平均拉伸结合强度为10.5MPa。扫描电镜观察证实，杂化层在牙本质与树脂界面处形成。

Adhesion to dentin is a key technology in adhesive dentistry but it is not accepted well even nowadays. The bonding mechanism is discussed based on the bonding strength, and SEM and TEM examination of bonded samples. Creation of hybrid layer in dentin-side adhesive interface is essential to make bonding of resin to dentin. The hybrid layer is not dentin, not resin but a mixture of dentin and cured resin. It is formed by polymerization of diffused and impregnated monomers in dentin. The rate of monomer diffusion is the functions of diffusibility of monomers and diffusivity of penetrated dentin. Monomers with both hydrophobic and hydrophilic groups can promote diffusion of monomers into the substrate. A variety of methacrylate-based materials have been developed with the capacity of adhering to dentin. In this project, the effectiveness of 2-(methacryloyloxy)ethyl phenyl hydrogen phosphate (Phenyl-P) for bonding 5% phenyl-P in methyl methacrylate to dentinal surfaces. The polymerization of the phenyl-P/MMA monomer was initiated by partially oxidized tri-n-butyl borane catalyst(TBB). The mean tensile bond strength of 5% phenyl-P in MMA to dentin that was pre- treated with an aqueous solution of 10% citric acid/3% ferric chloride was found to be 10.5MPa. The SEM observation confirmed that the hybrid layer was formed at the interface between dentin and resin.