A STUDY ON THE EFFECT OF DENTIN WITH VARIOUS PRETREATMENT APPLICATION TIME ON THE DENTIN SURFACE STRUCTURE AND THE BOND STRENGTH OF GLASS IONOMER RESTORATIVE MATERIALS

유치와 영구치 상아질의 전처리 시간에 따른 표면 미세구조 변화와 글라스 아이오너머 수복재의 결합력에 관한 연구

The main purpose of this study was to evaluate the effect of dentin with various pretreatment application time on the dentin surface structure and the bond strength of glass ionomer restorative matrials between primary and permanent tooth. There are difference of composition, structure and pretreated effect of dentin conditioning between the primary and permanent teeth. Inspite of thease fact, we used the same application time of permanent tooth. This study intends to determine the most effective application time using SEM analysis of the surface change by dentin conditioning. Forty five intact primary and permanent teeth were splited mesiodistally with seperating diamond disk. Each eight specimens were prepared for shear bond strength test. (randomely devided eight group as follows:) group I conditioning for five seconds group II conditioning for ten seconds group III conditioning for fifteen seconds group IV conditioning for twenty seconds Additional specimens were prepared to SEM analysis. The result are as follows: 1. Primary teeth are higher shear bond strength in group I and group II. 2. There was no statistically significant difference between primary and permanent teeth in group III and group IV. 3. In SEM analysis, smear layer removal by dentin pretreatment of primary teeth was faster than permanent teeth. Primary teeth may require shorter pretreatment time of dentin for G-I restoration than that of permanent teeth.