TANAKA Jiro Okayama Univ., Graduate School of Medicine and Dentistry, Assistant Prof., 大学院・医歯学総合研究科, 助手 (40171764)
IRIE Masao Okayama Univ., Graduate School of Medicine and Dentistry, Assistant Prof., 大学院・医歯学総合研究科, 助手 (90105594)
YOSHIDA Yasuhiro Okayama Univ., Graduate School of Medicine and Dentistry, Associate Prof., 大学院・医歯学総合研究科, 助教授 (90281162)
NISHIYAMA Norihiro Nihon Univ., School of Dentistry at Matsudo, Associate Prof., 松戸歯学部, 助教授 (90112953)
The bonding technique to tooth tissue including etching procedure and adhesive application was developed to get functional reconstruction of the caries in a wide area application. However, it is difficult to make a perfect bonding, a good characteristic of marginal gap closure, bonding strength and durability under a severe condition of buccal cavity. The main problem is on the formation and the physical properties of the interface layer between tooth tissue and resin. Therefore, we synthesize the amino acid derivative (NMωA) which has chemical compound affinity, especially by examining the interaction with dentinal collagen. In this study, in order to specify the NMωA formed by the interaction of collagen functional group, the relaxation time of NMωA in the collagen model chemical, compound that has an end part of imino unit and carboxyl unit was measured.
The measurement of ^<13>CNMR (T_1) is as follows. Oligopeptide of 10% (5 bodies of prolylprolylglycine, unit of protein/amino acid)
were dissolved in hydrochloric acid added deuterium oxide aqueous solution. The aqueous solution was manufactured at the pH of 1.7. After homogenized, 0.6g of this oligopeptide aqueous solution was placed in the NMR sample tube. 6.73×105 or 20.19 x 10^5 mol of NMωA was used as the NMR sample. T_1 was measured using an EX270MHz spectrometer (Nihon Denshi), which is performed with 180゜-τ-90゜ pulse sequence, in the temperature of 25℃.
As oligopeptides were coexist in NMωA aqueous solution, in order to examine an interaction of amide unit and carbonyl unit in the molecule of NMωA with the oligopeptide, the value of T_1 of carbonyl carbon which revert to these functional groups was similar to that was coexists in the deashing dentine. Compared to that of the non-coexistence chain, there was a great decrease. From the above result, the presents of amide and carboxyl unit in the molecule of NMωA showed that the side chains functional group of carbonyl unit and hydrogen bond in the collagen are formed. Furthermore, in case of hydroxymethacrylate (HEMA), it was identified that there was a strong interaction between the carbonyl unit in the same peptide and the carbonyl unit in the molecule. Less