RESUMO
BACKGROUND: To evaluate the tooth enamel surface morphology after the action of 35% hydrogen peroxide with and without LED activation. MATERIAL AND METHODS: 70 bovine incisors with an enamel surface of 4x4x3 mm were used, prepared for reading superficial microhardness and roughness. Specimens were randomly distributed and divided into 7 experimental groups (n = 10); G1 = artificial saliva; G2 = 35% HP - 2 sessions (3x15´); G3 = Phosphoric Acid + 35% HP - 3 sessions (3x15´); G4 = 35% HP - 2 sessions (3x15´) + blue LED; G5 = 35% HP - 2 sessions (3x15´) + green LED; G6 = 35% HP - 2 sessions (3x20´) + violet LED; G7 = Violet LED - 2 sessions (3x20´). The results were analyzed by the Anova, Wilcoxon, Dunnett and Tukey tests (α = 0.05). RESULTS: The G4 group showed a greater change in microhardness. Regarding roughness, the biggest mean difference between groups occurred in G2, G5 and G7. Optical microscopy showed a smooth enamel surface in groups G2, G5 and G7. CONCLUSIONS: Changes in the enamel surface were observed in relation to microhardness, but without significant changes in roughness, where the LED (green and violet) resulted in a smooth surface. Key words:Tooth whitening, superficial morphology, light, photoradiatio.
RESUMO
BACKGROUND: Dentin hypersensitivity (DH) is defined as an exaggerated sensitivity of vital dentin exposed to thermal, chemical and tactile stimuli. This study aimed to evaluate, through a literature review, the applicability of high- and low-intensity lasers in the treatment of DH for the past 10 years, as well as its therapeutic potential. MATERIAL AND METHODS: The electronic databases MEDLINE/PubMed and LILACS were searched using the descriptors ("Dentin Sensitivity" OR "Dentin Hypersensitivity") AND ("Low-Level Therapy" OR Laser), for articles published between 2010 and 2020. Only randomized clinical trials with full-text and full case resolution were included. RESULTS: We found 187 articles in total, among which 61 were pre-selected and 10 included in this literature review. CONCLUSIONS: Considering the found results and their possible limitations, high- and low-intensity lasers, associated or not with other therapies, have demonstrated beneficial effects in the treatment of DH, being considered a promising, safe, easy, and effective field of research, reducing pain sensitivity and preserving pulp vitality. Key words:Dentin sensitivity, dentistry, laser.