Objective: This study aimed to compare the effect of Er,Cr:YSGG laser with a tungsten carbide bur in orthodontic finishing on the enamel surface roughness and the heat generated in the pulp chamber. Methods: Before bonding, of 125 intact extracted premolar teeth, 15 teeth were randomly assigned to the control group. Of the remaining 110 bonded teeth, 50 were used to determine the laser parameters, and 60 were included in the main in vitro study. After debonding, the teeth were randomly distributed among four study groups (n = 15) for finishing with laser beams (Er,Cr:YSGG, Waterlase) with and without polishing with Sof-Lex discs, and finishing with a bur (tungsten carbide, Reliance) with and without polishing with Sof-Lex discs. The thermal changes were measured during finishing using a thermo-controller-coupled thermocouple placed in the pulp chamber. Enamel surface roughness was evaluated qualitatively under a scanning electron microscope (SEM) and quantitatively under an atomic force microscope (AFM). Results: The thermal changes of the bur group were significantly higher than those in the laser group (p = 0.0001). Quantitatively, the surface roughness values of all the study groups were significantly higher than those of the control group (p < 0.05), with no significant difference between the study groups (p > 0.05). SEM analysis confirmed the AFM measurements. Conclusions: Er,Cr:YSGG can be recommended as an alternative for a carbide bur for adhesive agent removal after orthodontic debonding, considering its mild thermal effect on the pulp. Polishing with Sof-Lex discs did not significantly reduce the surface roughness, regardless of the finishing procedure.
Keywords: YSGG laser; adhesive removal; finishing; surface roughness; thermal changes.