Effect of three collagen crosslinkers on the shear bond strength of self – etch adhesive system to dentin at varying time intervals.

Abstract

Abstract
 Background:
 When resin composite is bonded to dentin, the bond strength reduces with increase in depth of dentin. This is due to the increase in number of dentinal tubules, their diameter and less amount of intertubular dentin compared to “superficial dentin.21”
 Objective:
 This study proposes to improve bond strength of dentin to composite by biomodifying the dentin substrate prior to application of composite with three different crosslinking agents i;e Glutaraldehyde, Genipin and Riboflavin at varying time intervals.
 Method:
 42 extracted maxillary incisor teeth were selected. Teeth were sectioned to mesial and distal halves. (n=84). Specimens were divided into 4 groups. Group I was used as control group and Glutaraldehyde, Genipin and Riboflavin crosslinking agents were applied to other groups (II, III, IV) respectively before applying composite resin. These groups were further subdivided into A and B groups based on time of applying crosslinking agent. Shear bond strength was calculated for all specimens using universal testing machine. Results were analysed using Student t test for intra-group and inter-group comparison.
 Results:
 Greater bond strengths were recorded in all the groups compared to the control group. Application of Glutaraldehyde and Genipin as crosslinking agents reported higher shear bond strength compared to application of Riboflavin. The mean shear bond strength values further increased with increased application time of crosslinking agent. 
 Conclusion:
 Dentin surface pre-treatment with crosslinking agents at varying time intervals
 substantially improved the bond strength.