Effect of desensitizing treatments on bond strength of resin composites to dentin – an in vitro study

OBJECTIVES: Hypersensitivity is a common clinical multietiological problem. Many desensitizing treatments are there to overcome hypersensitivity. The aim of this study was to evaluate the effect of different dentin-desensitizing treatments on the tensile bond strength of composite restoration. MATERIALS AND METHODS: Twenty-four sound human molars were used. Enamel was wet abraded to expose flat dentin surfaces, polished with sandpaper. The specimens were then divided into three groups (n = 8) based on the type of dentin-desensitizing treatment given. The first group: G1 was the control group where no desensitizing agent was used. The second group: G2 was treated with desensitizing dentifrice containing a combination of potassium nitrate, triclosan, and sodium monoflorophosphate. The third group: G3 was treated with Er:YAG laser. Afterwards, the desensitized specimens were treated with one step self-etch adhesive according to manufacturer's instructions and composite microcylinders were packed. The specimens were then examined for tensile bond strength using universal tensile machine (KMI(TM) ). RESULTS: Statistical analysis of the data obtained revealed the mean values for the tensile bond strengths were 10.2613 MPa, 5.9400 MPa and 6.3575 MPa for groups 1, 2 and 3, respectively. These values were statistically significantly different between groups pretreated with laser or dentifrice as compared to control group. CONCLUSIONS: Dentifrice and Laser pre-treated dentin has lower tensile bond strength with resin composites as compared to dentin that is untreated.