Effect of different matrix metalloproteinase inhibitors on shear bond strength of composite attached to primary teeth dentin

Aim: This study is aimed to evaluate the effect of exogenous matrix metalloproteinases (MMPs) inhibitors on immediate shear bond strength (SBS) of resin composite attached to primary teeth dentin. Methods: Sixty extracted anterior primary teeth were selected. A dentin block (6.0 mm × 6.0 mm × 2.0 mm) was obtained from each tooth. All dentin blocks (n = 60) were pretreated for 60 s with either 0.01 M phosphate-buffered saline (pH 7.2) in the control group (Group I), chlorhexidine (CHX) 2% (Group II), doxycycline (DOX) solution 2% (Group III), and ethylenediaminetetraacetic acid (EDTA) 17% (Group IV) before applying etch-and-rinse adhesive system (Adper Single Bond 2). After adhesive application, composite resin (Filtek 3M, USA) was applied, and then, SBS values were determined with a universal testing machine. Results: There were no significant differences between SBS values of DOX, EDTA, and the control group (P