THE EFFECT of DENTIN PRETREATMENT on THE MICROTENSILE BOND STRENGTH of SELF-ADHESIVE RESIN CEMENTS

Statement of problem Self-adhesive cements have lower bond strength than conventional resin cements that rely on the application of etch-and-rinse adhesive systems. Purpose The purpose of this study was to evaluate the effect of tannic and polyacrylic acid on the microtensile bond strength of self-adhesive resin cements to dentin. Material and methods Eighteen molar crowns were flattened to expose dentin and divided into 3 groups according to the dentin pretreatment: (1) control, without surface treatment; (2) 25% polyacrylic acid solution (Ketac Conditioner); (3) 20% tannic acid. Composite resin (Tescera) blocks were luted to dentin surfaces using 2 self-adhesive resin cements (RelyX Unicem or Maxcem Elite) (n=3). All specimens were stored in distilled water for 24 hours, sectioned into beams (1 mm 2 ), and tested to failure using a microtensile method at a crosshead speed of 1 mm/min. The data were statistically analyzed using 2-way ANOVA and Fisher's PLSD tests (α=.05). Results The polyacrylic acid significantly improved the microtensile bond strength of RelyX Unicem (14.92 ±4.94 MPa) when compared to the control group (8.35 ±1.99 MPa) and tannic acid treatment (8.38 ±2.67 MPa) ( P Conclusions Dentin pretreatment with polyacrylic acid improved the microtensile bond strength of RelyX Unicem.