Effect of a desensitizer on microtensile bond strength of different adhesives / 대한치과보존학회지

ABSTRACT

This study evaluated the influence of a desensitizer(MS coat) on microtensile bond strength of different adhesives a three-step adhesive(All-Bond 2), a two-step adhesive(Single Bond), a one-step adhesive(One-up Bond F). Non-caries extracted human molars were used. Dentin surface was obtained by horizontal section on midportion of crown using a water-cooled low speed diamond saw. Teeth were randomly divided into 6 group. AMO(MS coat + All Bond)-, SMO(MS coat + Single Bond)- and OMO(MS coat + One-up Bond F)-dentin surface were treated with 17% EDTA before bonded adhesive. AMX-, SMX- and OMX-dentin surface were bonded with All-Bond 2, Single Bond and One-up Bond F, respectively, with no previous treatment with MS coat and 17% EDTA. About 1cm high resin composite(Z-250(TM)) were incrementally build-up on the treated surface. The specimens for the microtensile test were serially sectioned perpendicular to the adhesive layer to obtain 0.7x0.7 mm sticks. 30 sticks were prepared from each group. After that, tensile bond strength for each stick was measured with Microtensile Tester at a 1mm/min crosshead speed. Fractured dentin surfaces were observed under the SEM. The results were statistically analysed by using a One-way ANOVA and Tukey's test(p<0.05). Value in MPa were AMO-44.35+/-13.21; SMO-39.35+/-13.32; OMO-31.07+/-10.25; AMX-49.22+/-16.38; SMX-56.02+/-13.35; OMX-72.93+/-16.19. Application of MS coat reduced microtensile bond strengths of both Single Bond and One-up Bond F, whereas microtensile bond strengths of All-Bond 2 were not affected significantly.