Influence of dentin surface pre-treatment on microtensile bond strength of a single-bottle adhesive

Authors

  • Luiz Henrique Burnett Jr PUCRS
  • Bruno Lopes da Silveira
  • Alexandre Severo Masotti
  • Eduardo Gonçalves Mota PUCRS
  • Rosemary Sadami Arai Shinkai PUCRS

Keywords:

Dentin, dentin-bonding agents, tensile strength

Abstract

Purpose: This study evaluated the influence of different methods of dentin surface pre-treatment on microtensile bond strength and failure mode of a single-bottle adhesive. Methods: Twenty-four third molars were embedded in acrylic resin and ground until exposure of occlusal dentin. Six groups were tested according to the dentin surface pre-treatment: G1) 35% phosphoric acid (pa) (positive control); G2) slurry of pumice + pa; G3) air-abrasion with 25μm-aluminum oxide + pa; G3) air abrasion with 50μm-aluminum oxide + pa; G5) air abrasion with sodium carbonate + pa; G6) no treatment (negative control). The adhesive Single Bond (3M-ESPE) was applied on the dentin surface and photoactivated before a 6mm-height composite restoration was built (Z250, 3M-ESPE). After storage in distilled water at 37ºC for 24h, all specimens (sectional area of 1mm2) were subjected to a microtensile bond strength test at a crosshead speed of 0.5mm/min. Results: Bond strength mean values (MPa) were: G1=29.28, G2=21.04, G3=21.66, G4=18.94, G5=19.90, and G6=19.03. Only G1 was statistically different from the other groups (ANOVA and Tukey’s test, α=0.05). SEM images of the adhesive interface after rupture showed prevalence of mixed failure type (adhesive fracture between dentin and adhesive agent plus partial cohesive fracture in the composite restoration or dentin) for all groups but G6. Conclusion: The use of cleaning agents on dentin surface might not be necessary for adhesive procedures with dentin total acid-etching. Key words: Dentin; dentin-bonding agents; tensile strength

Author Biographies

Luiz Henrique Burnett Jr, PUCRS

Programa de Pós-Graduação em Odontologia Departamento Clínico Disciplinas de Dentistica I e II

Eduardo Gonçalves Mota, PUCRS

Programa de Pós-Graduação em Odontologia Departamento Clínico Disciplinas de Dentistica I e II

Rosemary Sadami Arai Shinkai, PUCRS

Departamento de Prótese Dentária. Programa de Pós-Graduação em Odontologia. PUCRS

Downloads

Published

2008-10-17

Issue

Section

Original Article