Andréa Dias Neves Lago

Evaluation of the Bond Strength Between a Composite Resin and Enamel Submitted to Bleaching Treatment and Etched with Er:YAG Laser

BACKGROUND The use of laser irradiation for dental surface treatment may increase tooth-composite bond strength. Its use on bleached teeth may decrease the waiting time between bleaching and restorative procedures. OBJECTIVE This study aimed to evaluate the bond strength between a composite resin and bovine enamel bleached with 35% hydrogen peroxide and etched with Er:YAG laser. MATERIALS AND METHODS Thirty bovine teeth were randomly divided into six groups (n = 5): G1, unbleached and restored 24 h after storage in artificial saliva, etching with 35% phosphoric acid (PA) (control); G2, unbleached and restored 24 h after storage in artificial saliva, etching with Er:YAG laser and 35% PA; G3, bleached and restored immediately afterward, etching with 35% PA; G4, bleached and restored 24 h after bleaching, etching with 35% PA; G5, bleached and restored immediately afterward, etching with Er:YAG and 35% PA laser; G6, bleached and restored 24 h after bleaching, etching with Er:YAG laser and 35% PA. Bond strength was quantitatively evaluated by microtensile test (1.0 mm/min). Data were submitted to statistical analysis using ANOVA and Tukey tests (α = 0.05). RESULTS Bond strength values (MPa) were G1, 26.17 ± 4.44; G2, 28.87 ± 3.94; G3, 17.25 ± 4.58; G4, 21.93 ± 5.02; G5, 16.69 ± 2.31; and G6, 29.06 ± 8.31. There was no statistically significant difference among groups G1, G2, and G6 (p = 0.119), which presented higher bond strength than group G4, followed by groups G3 and G5. CONCLUSION Er:YAG irradiation of bleached surfaces may favor bonding procedures when performed 24 h after bleaching.

Lingual Frenectomy with Diode High-Power Laser in an Adult Patient: A Case Report

Ankyloglossia or tongue-tie is a congenital dysfunction, characterized by abnormality of the lingual frenulum, where it can be adhered in a short form to the mouth floor or too close to the tip of the tongue generating difficulties to individuals.1–4 The lingual frenulum is a normal anatomic structure characterized by being a median fold that connects the tongue to the mouth floor; is exclusively constituted by fibrous dense conjunctive tissue, besides superior fibers of the genioglossus muscle.2,5 However, this structure is dynamic and modifiable, susceptible of changes on its shape, size and/or insertion during its embryonic formation.2,3