Development of Dentin Bonding System

本研究制备了5个不同降解阶段的EDPrimer II Liquid A系列底物，其中Liquid A底物中的HEMA分别被水解度为4.7%、39.2%、61.9%、66.7%和66.8%。研究了用于树脂核修复的ED Primer II Liquid A底漆对牙本质粘结耐久性的退化阶段影响。尽管树脂杂化胶原层的质量有所下降，但初始剪切粘结强度保持在大约12 Mpa，直到改变的液体A底物的降解阶段从4.7%到61.9%。然而，热循环的应用导致了树脂杂化胶原层的粘结强度和降解性能的特定降低。粘接强度的降低程度强烈地依赖于水解液A底漆的降解阶段。此外，还研制了三种实验自腐蚀底漆--由不同亚甲基链长的NM-ωR和NMGIy组成。这是为了研究NMωP衍生物中的亚甲基链长对钙盐的化学性质的影响，以及它对树脂与牙釉质和牙本质粘结强度的影响。核磁共振分析数据表明，随着NMωP结构中亚甲基链长的增加，脱钙的牙齿组分随着钙盐的形成由磷酸氢钙转变为磷酸钙。钙盐形成的差异与牙釉质的粘结强度从18 Mpa增加到24 Mpa有关，反映了NMωP钙盐疏水性的增加。然而，与牙本质的粘结强度保持在大约22兆帕不变。这种差异可能是由于NM-ω-P钙盐沉积在牙釉质和牙本质上的位置不同所致。

In this study, a series of five ED Primer II Liquid A primers in different stages of degradation, where the HEMA employed in the Liquid A primer had been hydrolyzed by 4.7,39.2,61.9,66.7 and 66.8 %, respectively, were prepared. The degradation stage effects of the ED Primer II Liquid A primers used for resin core restoration, on the dentin bond durability were examined. The initial shear bond strength remained unchanged at approximately 12 MPa until the degradation stages of the altered Liquid A primers ranged from 4.7 to 61.9 %, even though the quality of the resin hybridized collagen layer had decreased. However, the application of thermo-cycling resulted in specific decreases in the bond strength and degradation of the resin hybridized collagen layer. The degree of reduction in the bond strength was strongly dependent on the degradation stage of the hydrolyzed Liquid A primer.Furthermore, three experimental self-etching primers - consisting of NMωR with different methylene chain lengths and NMGIy - were developed. This was done with a view to investigating the effect of methylene chain length in NMωP derivatives on the chemical nature of calcium salts, as well as its effect on the bond strengths of resin to enamel and dentin. NMR analysis data showed that NMωPs decalcified tooth components with formation of calcium salts, which changed from calcium hydrogen phosphonate to calcium phosphonate with increase in methylene chain length within the NMωP structure. Disparity in calcium salt formation was related to increases in bond strength to enamel from 18 to 24 MPa, reflecting an increase in the hydrophobicity of NMωP calcium salt. However, bond strength to dentin remained unchanged at approximately 22 MPa. This difference probably arose from the dissimilar locations at which NMωP calcium salts were deposited on enamel and dentin.