Bond Strength of New One-bottle Adhesive on Dentin Surface Conditions

Objective: Studies have established the clinical success of one-bottle self-etching adhesive systems.  The purpose of this study was to compare micro-tensile bond (MTB) tests of a one-bottle adhesive system OptiBond All-in-One (Kerr, CA, USA) and a two-step adhesive system OptiBond Solo Plus Self-Etch Adhesive System (Kerr) on three different dentin surface conditions.  Methods: Non-carious extracted human molars were prepared with a diamond saw and the dentin surfaces were prepared with either an 180-grit SiC paper, a 600-grit SiC paper, or a diamond paste created smear free layer.  Each adhesive was applied to the dentin surface following manufacturer's instructions.  Clearfil AP-X resin composite (Kuraray Medical, Tokyo, Japan) was incrementally built to a height of approx. 10mm and light cured.  After 24-hrs storage in distilled water at 37ºC, MTB tests (bonded area 1.0X1.5mm, CHS=1.0mm/min) were performed using an Instron 4443 (n=15).  Data were analyzed by ANOVA and Tukey's test (p<0.05).  Results: The table shows both mean and S.D. in MPa.

Dentin Surface Condition	OptiBond All-in-One One-bottle system	OptiBond Solo Plus Self-Etch Two-step system
#180 grit SiC	52.0 (8.6)	21.6 (8.6)
#600 grit SiC	50.3 (9.4)	19.5 (5.7)
Diamond paste smear free layer	55.9 (11.7)	20.9 (9.5)

Conclusions: OptiBond All-in-One showed a significantly higher MTB strength to each surface condition than did OptiBond Solo Plus.  There were no significant differences of bond strength amongst the three-dentin surface conditions of each adhesive system.  Our data suggests that MTB strengths of the two adhesive systems were not affected by dentin surface conditions.