Effect of Chlorhexidine on Dentin Bonding Strength

Objectives:

The purpose of this study was to evaluate the effect of using chlorhexidine on dentin shear bond strength with three types of adhesive systems: total-etch, self-etch and all-in-one.

 

Methods:

One hundred and twenty extracted caries-free human teeth were obtained for this study. Each tooth was embedded in acrylic resin. Flat dentin surfaces were prepared using SiC paper to 320 grit (Ecomet. Buehler). Three adhesive systems were tested:  total etch (Peak LC Bond, Ultradent Inc), self-etch (Peak SE Primer, Ultradent Inc) and all-in-one (Adper Easy Bond, 3M/ESPE). All adhesives were applied according to manufacturers' instruction. Filtek Supreme Plus (3M ESPE) composite was filled into a bonding jig and cured for 40 seconds with LED curing light (DEMI, Kerr). For chlorhexidine (CHX) application, 0.2% CHX was applied for 1 minute on the dentin after the etched procedure on group 1, prior to peak SE procedure on group 2 and prior to composite restoration for group 3.  All samples were aged in artificial saliva for 1 month at 37°C. The 6-month aging samples are under way. Shear bond testing was carried out using universal testing machine (Instron 5566A, Norwood, MA) with crosshead speed of 0.5mm/min. Statistical analysis was done by one-way ANOVA, with post-hoc analysis conducted via Tukey's HSD. Statistical significance was predetermined at level p<.05.

 

Results:

Adhesive systems	Control (MPa+SD)	0.2% CHX (MPa+SD)
Group 1 TE	25.7±6.8	22.8±8.2
Group 2 SE	30.3±6.5	34.8±9.5
Group 3 All-in-one	27.2±11.4	35.2±11.5

 

Conclusions:

The one-month aging result showed no statistical differences in between control groups. With additional application of CHX, there was a statistical difference in bond strengths of group 1 compared with groups 2 and 3.