In this randomized clinical trial, patients with NCCLs will be included (four teeth in each participant). After class V cavity preparation in the NCCLs, the teeth will be randomly assigned into four groups according to diode laser irradiation wavelength Group 1 (placebo) laser simulation and Group 2 (445 nm) diode laser wavelength, Group 3 (660 nm) diode laser wavelength, and Group 4 (970 nm) diode laser wavelength. Following laser irradiation, the universal self-etch adhesive will be applied and all the cavities will be restored with the same resin composite. Tooth sensitivity to a cold stimulus will be recorded using a visual analogue scale (VAS) before treatment and on follow-up days 1, 14 followed by 1, 3, and 6 month after treatment.
This study will investigate the efficacy of three diode laser wavelengths 445 nm, 660 nm, 970 nm when applied just before placement of composite restoration on reducing postoperative sensitivity from Non-carious cervical lesions (NCCLs) with class V cavity preparation.