Effect of Tooth Surface Preparation on the Bonding of Self-Etching Primer Adhesives

The aim of this study was to determine the bonding effectiveness of four self-etching primer adhesives after various tooth preparation protocols. Enamel/dentin specimens were prepared from 84 permanent molars, divided into three enamel preparation groups (silicon carbide paper [SiC]; erbium, chromium:yttrium, scandium, gallium, garnet [Er,Cr:YSGG] laser [EL] and diamond bur [DB]) and five dentin preparation groups (SiC, EL, DB, steel [SB], and ceramic burs [CBs]). In each group, specimens were equally divided into four subgroups and were bonded using Clearfil SE Bond (CSE, Kuraray), Xeno IV (XE, Dentsply), Tokuyama Bond Force (TX, Tokuyama) and Filtek Silorane System Adhesive (FS, 3M ESPE), as well as a hybrid resin composite (Clearfil Majesty Esthetic, Kuraray) for CSE, XE, and TX, and Filtek Posterior Restorative (3M ESPE) for FS). After 24 hours of water storage at 37 degrees C, microshear bond strength (mu SBS) testing was carried out. Data were analyzed using analysis of variance (ANOVA)-Tukey test at alpha=0.05 and bond failure modes assessed. Representative debonded specimens were prepared and examined under the scanning electron microscope (SEM). All adhesives exhibited no significant differences in mu SBS on enamel and dentin under the clinical cavity preparation protocols, except for TX on dentin. SEM revealed areas of altered subsurface enamel/dentin following EL ablation.