Effect of Air-Blowing Time on The Microshear Bond Strength of Two Universal Adhesives to Enamel and Dentin

Abstract

Objectives: The aim of this study was to investigate the effect of air blowing time on the microshear bond strength of two universal adhesives to enamel and dentine. Materials and methods: Thirty extracted sound human molars were used. Flat enamel and dentin surfaces were obtained by removing the buccal enamel surface of each tooth exposing the buccal enamel and dentin. The teeth were randomly divided into two equal groups (N= 15) according to the tested adhesive system either Single Bond Universal (SBU) or all bond universal (ABU). Each group was further divided into 3subgroups (N= 5) according to the air blowing time i.e (5 seconds, 10 seconds, and 15seconds). Each subgroup was further subdivided into two divisions according to the substrate either enamel or dentin. Each substrate received 2 resin composite microrods (N=10). After storage in distilled water (37°C/24 h), microshear bond test was performed in a universal testing machine. One-way ANOVA followed by Tukey post-hoc test was used to compare between more than two groups in non-related samples. Two-way ANOVA was used to test the interaction between different variables. Results: There was a statistically significant difference between (15sec), (10sec) and (5sec) groups for (SBU) and (ABU) in enamel (p≤ 0.001). There was also statistically significant difference between (15sec), (10sec) and (5sec) groups for (SBU) and (ABU) in dentin (p <0.001). Conclusions: Air blowing time of 15 seconds in enamel has a positive effect on microshear bond strength of universal adhesives. Air blowing time effect in dentin was material dependent.