Effects of a peripheral enamel bond on the long-term effectiveness of dentin bonding agents exposed to water in vitro

✍ Scribed by Andre F. Reis; Marcelo Giannini; Patricia N. R. Pereira

• Publisher: John Wiley and Sons
• Year: 2008
• Tongue: English
• Weight: 694 KB
• Volume: 85B
• Category: Article
• ISSN: 1552-4973
• DOI: 10.1002/jbm.b.30909

✦ Synopsis

Abstract

This study evaluated the effects of water exposure on the in vitro microtensile bond strength (μTBS) of etch‐and‐rinse and self‐etching adhesives to human dentin over a 1‐year storage period. Five adhesive systems used were as follows: a one‐step self‐etching adhesive (One‐up Bond F‐OB), two two‐step self‐etching primers (Clearfil SE Bond‐SE and Clearfil Protect Bond‐CP), and two etch‐and‐rinse adhesives (Single Bond‐SB and Prime&Bond NT‐PB). Dentin surfaces were bonded, restored, and assigned to four subgroups, according to the degree of water exposure: 24 h of peripheral water exposure (24 h‐PE) (having circumferential enamel); and 1 year of peripheral exposure (1 yr‐PE), direct exposure (1 yr‐DE) (dentin directly water‐exposed), or directly exposed to oil only (no water exposure) (1 yr‐DOE). A composite‐enamel bond adjacent to the restoration is determined if the water exposure was peripheral or direct. After storage periods, specimens were serially sectioned, trimmed to an hourglass shape with a cross‐sectional area of 1 mm^2^ at the interface, and tested in tension. Results were analyzed by two‐way ANOVA and Tukey test (α = 0.05). No difference was found between 24 h‐PE and 1 yr‐PE for OB, CP, SB, and PB. However, μTBS values significantly dropped after 1 yr‐DE for SE, CP, SB, and PB. A decreased μTBS was seen in SE after 1 yr‐PE, but no differences existed between 1 yr‐PE and 1 yr‐DE. Similar or increased μTBS values were noted in 1 yr‐DOE for all adhesives. Water‐storage for 1 year significantly decreased μTBS for all adhesives. However, except for SE, the presence of a peripheral composite‐enamel bond seemed to reduce the degradation rate in resin‐dentin interfaces for all materials. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008