A comparison of the micro-shear bond strength and failure mode of non-enclosed and mold-enclosed luting cements bonded to metal

Abstract

The objective of the study was to compare 1) the mean micro-shear bond strength and 2) failure mode of cements to metals in nonenclosed and mold-enclosed specimens. Specimens were prepared in mold-enclosed and non-enclosed formats from two RMGIC's and a self-adhesive resin-cement. 3-way ANOVA analysis and Tukey post hoc tests were used to compare mean µSBS results (α=0.05). Failure mode was analysed with Pearson's chi-square test (α=0.05). µSBS was significantly affected by the factors substrate and method (p<0.001) but not by material (p=0.077). There was an interaction between substrate, method and material F (2,144)=3.57, p=0.031, and method and material (2,144)=5.86, p=0.004. All mold-enclosed specimens for the three cements bonded to titanium and non-precious metal exhibited higher (p<0.001) mean µSBS than the non-enclosed specimens. Within this study, mold-enclosed specimens exhibited significantly higher (p<0.001) mean µSBS and adhesive failure compared to non-enclosed specimens.

Relationship between enamel bond fatigue durability and surface free‐energy characteristics with universal adhesives

“…However, there were no significant differences in failure mode after either the initial shear bond strength or shear fatigue strength tests, and adhesive failures were the most frequently observed type of failure, regardless of the presence or absence of pre‐etching and type of adhesive. This is not surprising, as the bond strength testing was performed using a mold‐enclosed method, which is known to result in an increase in adhesive failures . Previous studies have reported that the bond durability of universal adhesives to phosphoric acid pre‐etched enamel is higher than that to ground enamel, and these findings are consistent with the results in the present study.…”

Relationship between mechanical properties and bond durability of short fiber‐reinforced resin composite with universal adhesive

“…In the present study, the shear load was applied directly to metal rings enclosing the resin composite bonded to dentin. It has been reported that metal mold‐enclosed bonding specimens exhibit a higher frequency of adhesive failure than do non‐metal mold‐enclosed bonding specimens . This may be one of the reasons why adhesive failures predominated, regardless of the type of resin composite in this study.…”

Comparison between universal adhesives and two‐step self‐etch adhesives in terms of dentin bond fatigue durability in self‐etch mode

“…In the present study, the shear load was applied to the metal rings enclosing the resin composite bonded to dentin, and adhesive failures were observed most frequently, regardless of the type of adhesive. This can be explained by the fact that bonding specimens enclosed within a metal mold exhibit a higher frequency of adhesive failure than do unenclosed specimens . A previous study has stated that an increased incidence of adhesive failure in bond strength tests is desirable to provide more relevant information about the mean bond strength .…”