A Study on One-step Adhesive Systems : Assessments of Bond Abilities and Contributions of Technique Sensitivities on Bonding Procedures

Abstract

Recently, some manufacturers have developed new resin adhesive systems in which the conditioning, priming, and bonding procedures are set into one step. In those systems, clinical manipulations and procedures are so improved and simplified that clinicians are allowed to use them, and they do so more effectively. However, it is important to understand the effect of each treatment, especially adhesive application duration and air-blowing, since these can be the technique-sensitive factors of one-step adhesive systems. The purposes of this study were: 1) to compare the bond strength of seven kinds of one-step adhesive systems using microtensile bond testing and dye penetration testing, and 2) to investigate the influence of the adhesive application duration and airblowing variables on dentin bond strength of onestep odhesive systems: S³ Bond and G-Bond. 1) Freshly extracted human molars were used in this study. The dentin surfaces were created using abrasive paper. S³ Bond (Kuraray), G-Bond (GC), Adper™Pronpt™L-pop™(3M), Absolute (Dentsply Sankin), One-up Bond F Plus (Tokuyama Dental), AQ Bond Plus (Sun Medical), and iBond (Heraeus Kulzer) were used in this study. According to each manufacturer's instruction, adhesives were applied to prepared dentin surfaces, and then composite resins were placed onto each bonded experiment surface. After 24h, microtensile bond testing was performed in a bonded area of 1.0 × 1.0 mm at a crosshead speed of 0.5 mm/min. Cylinder-shaped cavities were prepared on the enamel surfaces of extracted human molars. These specimens were treated according to each manufacturer's instruction, and composite resins were condensed and then lightactivated. Bonded specimens were subjected to thermal cycling between 5-60℃ for 1,000 repetitions. 2) Freshly extracted human molars were used, and S³ Bond and G-Bond were employed in this study. The prepared dentin surfaces were treated according to each manufacturer's instructions and with various adhesive application durations (long or short) and air-blowing (gentle or hard). Microtensile bond tests were performed, and SEM observation was also performed to examine each of the resin-dentin interfaces. The results were as follows: 1) all of the seven kinds of one-step adhesive systems demonstrated good bonding performances, and there were no significant differences between the thickness of the resin bonding layer and the microtensile bond strength; 2) the dentin bond strength of S³ Bond and G-Bond decreased with various adhesive application durations and air-blowing. This tendency was more pronounced with G-Bond.