ABSTRACT
Objective:To examine the effect of acid etching time on the bonding interface of non-carious cervical sclerotic dentin. Methods: Twenty extracted premolars with non-carious cervical lesions were randomly divided into two groups, the lesion surface was conditioned with Scotchbond Multi-Purpose Plus dentin bonding system. The etching time was 15 s and 30 s respectively. The bonding interface ultra-structures were compared with SEM. Results:In sclerotic dentin (15 s) , the hybrid layer was visible, with minimal resin tags in the dentinal tubules and, when presented, they were shorter. Doubling the etching time (30s) resulted in more resin tags with an hybrid layer formation on peritubular dentin. Conclusion: Doubling the etching time improved the ultrastructure of sclerotic dentin-resin bonding interface, and could be an efficient way to improve the bonding effect.