Microtensile bond strength of resin composite to dentin treated with Er:YAG laser of bleached teeth.
Lasers Med Sci
; 27(1): 31-8, 2012 Jan.
Article
em En
| MEDLINE
| ID: mdl-20859649
The objective of this study was to evaluate the influence of Er:YAG laser (λ = 2.94 µm) on microtensile bond strength (µTBS) and superficial morphology of bovine dentin bleached with 16% carbamide peroxide. Forty bovine teeth blocks (7 × 3 × 3 mm(3)) were randomly assigned to four groups: G1- bleaching and Er:YAG irradiation with energy density of 25.56 J/cm(2) (focused mode); G2 - bleaching; G3 - no-bleaching and Er:YAG irradiation (25.56 J/cm(2)); G4 - control, non-treated. G1 and G2 were bleached with 16% carbamide peroxide for 6 h during 21 days. Afterwards, all blocks were abraded with 320 to 600-grit abrasive papers to obtain flat standardized dentin surfaces. G1 and G3 were Er:YAG irradiated. Blocks were immediately restored with 4-mm-high composite resin (Adper Single Bond 2, Z-250-3 M/ESPE). After 24 h, the restored blocks (n = 9) were serially sectioned and trimmed to an hour-glass shape of approximately 1 mm(2) at the bonded interface area, and tested in tension in a universal testing machine (1 mm/ min). Failure mode was determined at a magnification of 100× using a stereomicroscope. One block of each group was selected for scanning electron microscope (SEM) analysis. µTBS data was analyzed by two-way ANOVA and Tukey test (α = 0.05). Mean bond strengths (SD) in MPa were: G1- 32.7 (5.9)(A); G2- 31.1 (6.3)(A); G3- 25.2 (8.3)(B); G4- 36.7 (9.9).(A) Groups with different uppercase letters were significantly different from each other (p < .05). Enamel bleaching procedure did not affect µTBS values for dentin adhesion. Er:YAG laser irradiation with 25.56 J/cm(2) prior to adhesive procedure of bleached teeth did not affect µTBS at dentin and promoted a dentin surface with no smear layer and opened dentin tubules observed under SEM. On the other hand, Er:YAG laser irradiation prior to adhesive procedure of non-bleached surface impaired µTBS compared to the control group.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Resistência à Tração
/
Colagem Dentária
/
Resinas Compostas
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Dentina
/
Lasers de Estado Sólido
Limite:
Animals
Idioma:
En
Revista:
Lasers Med Sci
Assunto da revista:
BIOTECNOLOGIA
/
RADIOLOGIA
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Brasil
País de publicação:
Reino Unido