Bonding Characteristics and Reliability of All-in-one Adhesive Systems Based on Immediate Tensile Bond Strength

Abstract

An understanding of the characteristics and reliabilities of dental materials and devices prior to clinical use is one of the responsibilities required of all general practitioners in order to give high-quality dental treatment to patients. The purpose of this study was to examine the bonding characteristics and reliabilities of all-in-one resin adhesive systems based on their immediate tensile bond strength (ITBS). Six typical all-in-one resin adhesive systems on the market were selected. The ITBS of those systems to both enamel and dentine surfaces of a standardized V-shaped cavity prepared in the buccocervical region of extracted human upper premolars was measured with an in vivo/in vitro bi-use portable adhesion tester. Furthermore, debonded surfaces after the bond test were observed with a digital microscope. The data of the ITBS were examined using two-way ANOVA, Tukey's q-test and Weibull analysis. The six systems indicated significantly higher bond strengths when the bonded surface was dentine rather than enamel. The reliability of acquiring bond strength peculiar to each system varied among the systems. The systems could be divided into two groups by reliability: those which exhibited excellent reliability when the bonded surface was enamel and those which demonstrated higher reliability for the dentine surface. The adhesion of the six systems to enamel and dentine characterized by the ITBS depended on the differences in oral environmental factors and systems. When the bonded surface was enamel, there were significant differences in the reliability of acquiring bond strength peculiar to each system among the six systems, but no remarkable superiority or inferiority of specific systems was found. When the bonded surface was dentine, significant differences in the reliability were found, and also the superiority or inferiority of specific systems was confirmed. The influence of oral environmental factors on bonding durability to both enamel and dentine varied among the systems. Mixed fracture was mainly observed on the debonded surfaces after the bond test.