Orthodontics and Endodontics

Background and Aims: This study investigated the combined effect of Co2 laser irradiation and Remin Pro paste on treatment of enamel white spot lesions (WSLs).

Materials and Methods: Seventy-eight intact premolars were randomly assigned into six groups and then stored in a demineralizing solution to create WSLs. Afterwards the teeth in group 6 (negative control) remained untreated while groups 1 and 4 were exposed to Co2 laser irradiation (20 Hz, 1W, 30 seconds) and Remin Pro paste, respectively. In groups 2 and 3 teeth were exposed to laser either before (group 2) or after (group 3) Remin Pro application. Teeth in groups 1 to 5 were then immersed in artificial saliva for 90 days while subjected to fluoride mouthwash and weekly brushing. Finally, teeth were sectioned and Vickers microhardness was measured at the enamel surface and at 50,100 and 150μm from the surface. One sample of each group was also examined with scanning electron microscope (SEM). Data were analyzed by two-ways Analysis of variance (ANOVA) and Tukey test. The significance was set at 0.05.

Results: Laser irradiation followed by Remin Pro application (group 2) caused a significant increase in total WSLs’ microhardness compared to laser alone (group 1) and control groups (p<0.05). Microhardness at depths of 100 and 150 μm was also significantly greater in group 2 compared to those of group 3 and control groups (p<0.05).

Conclusion: Combined application of Co2 laser with Remin Pro paste, when laser is irradiated before the paste, is suggested for rehardening of WSLs.