An improvement of experimental primer of light-cured glass ionomers

1.稳定性试验本研究的目的是评价实验底漆储存温度对光固化玻璃离子水门汀粘接强度的影响。使用了三种自酸蚀底漆，富士离子II型LC(GC)和固化单元GC New Light VL-II(GC)。采用气相色谱的方法制备了底漆，其主要成分为：1)磷酸盐单体，2)碳酸，3)玻璃聚烯酸。结果表明：1.牙本质粘结强度随储存时间的延长而显著降低，储存温度越高，粘结强度下降趋势越明显；2含玻璃聚烯酸的自酸蚀底漆粘结强度最高。本研究的第二阶段是使用实验性自酸蚀玻璃聚烯酸底漆进行LCGIC的临床试验，并评价6个月的临床表现。根据改良的USPHS标准对LCGIC进行临床评价。用印模制作的环氧体模型，对修复牙的形态变化进行扫描电子显微镜观察。日本大学牙科医院对此次临床评估的准备工作已经完善。然而，开展这一项目不可能获得卫生和福利部的授权。临床评估将一直进行到获得许可为止。

1. Stability performance testThe aim of this research project was to evaluate the influence of the storage temperature of experimental primer on bond strength of light-cured glass ionomer cement (LCGIC). Three self-etching primers, Fuji ionomer type II LC (GC), and curing unit GC New light VL-II (GC), were employed. Employed primer were made by GC and their main composition were ; 1) phosphate-monomer, 2) carbonic acid, and 3) glass polyalkenoic acid. By evaluating shear bond strength and comparing the SEM interfacial morphology, Following results were obtained.1 The dentin bond strengths were significantly decreased with longer storage periods, and this tendency was pronounced with higher storage temperatures.2 The highest bond strength was obtained with the use of the self-etching primer containing Glass polyalkennoic acid.2. Clinical performance evaluationThe second stage of this study was to conduct the clinical trail of LCGIC with use of the experimental self etching glass polyalkenoic acid primer and evaluate 6 month clinical performance., Fuji ionomer type II LC (GC), and curing unit GC New light VL-II (GC) were employed. LCGIC were clinically evaluated according to the modified USPHS criteria. SEM observation was also performed for the morphological change of restored teeth using epoxy models made form impression. The preparation of Nihon Univ.dental hospital on this clinical evaluation has been perfect. However, it is not possible to receive the authorization for conducting this project from Ministry of Health and Welfare. The clinical evaluation will carry out till the permission is received.