Abstract
Aim: To evaluate the effects of 10% NaOCl gel application on the dentin bond strengths and morphology of resin-dentin interfaces formed by three adhesives. Methods: Two etch-and-rinse adhesives (One-Step Plus, Bisco Inc. and Clearfil Photo Bond, Kuraray Noritake Dental) and one self-etch adhesive (Clearfil SE Bond, Kuraray Noritake Dental) were applied on dentin according to the manufacturers’ instructions or after the treatment with 10% NaOCl (ED-Gel, Kuraray Noritake Dental) for 60 s. For interfacial analysis, specimens were subjected to acid-base challenge and observed by SEM to identify the formation of the acid-base resistant zone (ABRZ). For microtensile bond strength, the same groups were investigated and the restored teeth were thermocycled (5,000 cycles) or not before testing. Bond strength data were subjected to two-way ANOVA and Tukey’s test (p<0.05). Results: NaOCl application affected the bond strengths for One-Step Plus and Clearfil Photo Bond. Thermocycling reduced the bond strengths for Clearfil Photo Bond and Clearfil SE Bond when used after NaOCl application and One-Step Plus when used as recommended by manufacturer. ABRZ was observed adjacent to the hybrid layer for self-etch primer. The etch-and-rinse systems showed external lesions after acid-base challenge and no ABRZ formation when applied according to manufacturer’s instructions. Conclusions:10% NaOCl changed the morphology of the bonding interfaces and its use with etch-&-rinse adhesives reduced the dentin bond strength. Formation of ABRZ was material-dependent and the interface morphologies were different among the tested materials.
Highlights
Received for publication: November 17, 2015 Accepted: December 22, 2015Correspondence to: Marcelo GianniniDepartamento de Odontologia Restauradora Faculdade de Odontologia de Piracicaba – UNICAMPAv
The first tested hypothesis, that 10% NaOCl and thermocycling would not reduce dentin bond strengths regardless the type of adhesive system used, was rejected because the dentin bond strengths of adhesives were reduced with 10% NaOCl application and thermocycling
The second hypothesis stating that 10% NaOCl application would not provide the acid-base resistant zone (ABRZ) formation was rejected, because the self-etch adhesive system formed ABRZ even with NaOCl application after etching
Summary
Received for publication: November 17, 2015 Accepted: December 22, 2015Correspondence to: Marcelo GianniniDepartamento de Odontologia Restauradora Faculdade de Odontologia de Piracicaba – UNICAMPAv. The advancement of Adhesive Dentistry produces restorations with excellent aesthetic and mechanical properties; even so, the restorative procedures still present some clinical problems related to microleakage and degradation. Such problems could occur from gap formations between tooth and adhesive restoration, which can lead to secondary caries and fractures in adjacent dental structures, affecting the longevity of restorations[1]. Many studies have evaluated the prevention and control of secondary caries around composite restorations, mainly in dentin. The focus of these investigations has been on e resin-adhesive interfaces after cariogenic challenge.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
