Effect of Chlorhexidine in Dentin Bond using Total-Etch and Self-Etch

Objectives: The current study evaluated the effect of chlorhexidine (CHX) on the bond strength (BS) of a self-etch and total-etch adhesives to dentin over a six-month period using two modes of CHX application; a topical application of 0.2% CHX to dentin surface and Peak CHX, a resin incorporating 0.2% CHX.

Methods: Occlusal dentin surface was prepared from caries-free extracted human molars. Dentin surface was etched with Ultra-etch or conditioned with Peak SE primer. 0.2% CHX solution was applied to half of experimental groups for 60 sec and excess solution was absorbed with paper followed by Peak LC bonding agent. The remaining experimental groups were treated with Peak CHX. Filtek Supreme Ultra composite was placed on the sample using an Ultradent jig. Bonded samples were stored in 37°C water for 1 month or 6 months then subjected to occlusal shear bond testing at a crosshead speed of 0.5mm/min. A non-parametric method, wilcoxon analysis was used for statistical analysis.

Results: After 1 month storage in artificial saliva, there was no significant difference between all groups. After 6 month storage, 0.2% CHX and Peak CHX groups showed significantly higher BS compared to control groups in both total-etch (p= 0.0284 and 0.0015) and self-etch (p=0.0003 and 0.0002). There was no significant difference between two modes of CHX application (p > 0.05).

Mean Bond Strength (MPa) with Standard Deviation

	Total-Etch
	Control	0.2% CHX	Peak CHX
1 Month	32.809 (±8.646)	29.583 (±5.575)	31.053 (±7.160)
6 Month	16.896 (±1.724)	21.024 (±4.746)	23.788 (±5.011)
	Self-Etch
1 Month	34.923 (±6.313)	30.458 (±8.918)	32.198 (±6.908)
6 Month	15.762 (±2.245)	26.395 (±6.165)	29.547 (±5.487)

 

Conclusions: Both total-etch and self-etch adhesive systems benefited from CHX application over a six-month time period. Two modes of CHX application were similarly effective in preserving dentin BS.