2단계 산부식형 접착제와 이중중합형 복합레진의 적합성에 대한 접착레진의 효과

Abstract

This study was performed to investigate the effect of intermediate bonding resin used to overcome the incompatibility of two-step total-etching adhesives with dual cure composite resin. Two methods for overcomming incompatibility were investigated : Dual cure activators (Optibond solo plus Activator, Prime&Bond NT Self cure activator, Exite DSC), additional application of the intermediate bonding resin layer(D/E resin). Three two-step total-etching adhesives (Optibond solo plus, Prime&Bond NT, Exite) were used for the adhesion of the dual cure composite resin (MultiCore Flow). Dual cure composite resin was polymerized with a delayed light-activation mode. Nine groups were tested: 1)ON (Optibond solo plus), 2)OA (Optibond solo plus and activator), 3)OB (Optibond solo plus and bonding resin), 4)NN (Prime&Bond NT), 5)NA (Prime&Bond NT and activator), 6)NB (Prime&Bond NT and bonding resin), 7)EN (Exite), 8)EA (Exite DSC), 9)EB (Exite and bonding resin). Human molar were sectioned to exposed the occlusal dentinal surfaces of crown with Isomet Low Speed Saw and slabs of 1.2mm thick were made. Each two-step total-etching adhesives were applied on dentinal surfaces as a instruction of manufacturer and dual-cure composite resin was placed on the dentinal surface using Tygon tubes. Microshear bond strength was tested at a crosshead speed of 1.0 mm/min. The data were statistically compared using two-way ANOVA, Tukey HSD test. Also fractured interfaces were examined under SEM examination. The results from this study were as follows: 1. In comparison among groups using Optibond solo plus, μSBS of the OA group was lower than that of the ON, OB group (p < 0.05) and the OB group was measured with the highest bond strength (p < 0.05). 2. In comparison among groups using Prime&Bond NT, μSBS of the NA group was lower than that of the NN group but it was not statistically significant (p > 0.05) and the NB group was measured withthe highest bond strength (p < 0.05). 3. In comparison among groups using Exite, μSBS of the EA group was higher than that of the EN group (p < 0.05). The μSBS of the EB group was the highest bond strength (p < 0.05). 4. In fractured interfaces of the ON, EN group, a large cluster of globular voids representing incompatibility were examined. In the OB, NB, EA, and EB group, no voids were examined and mixed failure of the dual cure composites occurred predominantly. Because of the incompatibility between adhesives and composites, adhesives must be selected carefully when core was restored by dual cure or self cure composites. Dual cure activators used on purpose to overcome the incompatibility showed mostly ineffective but, the intermediate bonding resin layer was effective to improved bond strength of two-step total-etching adhesives with dual-cure composite resin.