광중합 코팅제에 따른 수복용 글라스 아이오노머 시멘트의 경도 변화 = EFFECT OF LIGHT-CURED COATING AGENTS ON THE HARDNESS OF RESTORATIVE GLASS IONOMER EMENTS

다국어 초록 (Multilingual Abstract)

This study was done to compare the effect of various surface coating on harness for three different glass ionomer cements. The glass ionomer cements used were self-curing, light-curing and water hardening glass ionomer cement.
The experimental groups were coated with Fuji Coat LC, Ketac-Glaze, Fortify, Schotchbond 2 and Fuji Vanish while the control group was uncoated. The half of the experimental groups were stored in 37℃ air, and the others wee placed in lactic acid solution. The surface harness for each specimen was then measured after 15 minutes, 1 hour, 1 day, 7 days and 30 days using a Vickers microhardness tester.
From the experiment, the following results wer obtained ;
1. In general for the glass ionomer cements without protective surface coating, stroing in air showed the large hardness number and produced dehydration, which caused increase in hardness with time. After immediately mixing (15 min.) of cements, the glass ionomer cements without surface coating ranked in order of high value of surface hardness were water-hardening, glass ionomer cement, light-curing glass ionomer cement and self-curing glass ionomer cement.
2. The hardness of the glass ionomer cement with aged in lactic acid soultion was smaller than that in air. The surface damage resulting from dissolution in lactic acid caused a commensurate decrease in harness with time.
3. The combination of the self-cured glass ionomer cements and GL or FCS coating material appeared to be more effective than others in providing an enhanced hardness. The light-cured glass ionomer cement showed a relatively high in surface harness when the surface coating materials KGL, FCS and SLA were applied. The FCS coating material leaded to a significant improvement in the surface hardness for the water-hardened glass ionomer cement.