Effect of 940nm laser diode irradiation prior to bonding procedure on postoperative sensitivity following class II composite restorations: a split-mouth randomized clinical trial.

Abstract

The aim of this study was to evaluate the effect of 940nm laser diode on class II composite cavities prior to bonding and restoration process on the postoperative sensitivity (POS). Thirty patients with two bilateral premolars with mesio or disto-occlusal carious lesions were evaluated. In each patient, the teeth were randomly divided into the control and laser groups. After cavity preparation and isolation and before the bonding process, the laser group was subjected to 940nm irradiation (Epic 10, Biolase, USA) by 400μ tip continuously at 100mW with 398J/cm2 energy density of tip, which was applied for 5s at a distance of 2mm on the axial wall of the cavity. In the control group, irradiation was performed by using the aiming beam. Access cavity was then restored with a composite resin. Cold sensitivity was measured using a cold spray application on the middle third of teeth buccal surface at baseline (before the intervention), 1, 14, and 30days after the restoration by visual analog scale (VAS) criteria. The mean Friedman and Wilcoxon signed-rank tests were used for data analysis. It was shown that in both laser and control groups, the VAS was significantly decreased at all times compared to the baseline (p≤0.05). There was no statistically significant difference between the mean VAS of two groups at baseline and first day (p≤0.05), but at 14 and 30days after the intervention, it was significantly lower in the laser group (p≤0.05). The results of this study demonstrated that the cavity pretreatment with laser diode (940nm) effectively reduces the postoperative sensitivity in class II composite restorations.