Efffect of desensitizing agents on the bond strength of dental adhesive systems

Abstract

Abstract The exposure of dentin to the oral environment leads to dentinal sensitivity, the treatment of which exposes the substrate to various substances that can alter its interaction with adhesive restorative materials. The objective of this study was to analyze whether the prior use of desensitizing agents interferes with the bond strength of resin restorative materials. A total of 48 molars were divided into six groups, according to conventional application (CV) of the adhesive systems Scotchbond Multipurpose (SB) and Clearfil SE Bond (CF) and their association with bioglass (BG/Biosilicate®) or arginine (AR/Sensitive Pro-Relief/TM). Bond strength was assessed by a microshear mechanical test, using a composite resin as restorative material (Filtek Z350 XT). Mechanical testing was performed at a speed of 0.5 mm/min in a universal testing machine, and the data were submitted to two-way ANOVA and Tukey’s test (α = 0.05). The bond strength (MPa) was 17.03 for SBCV; 21.19 for SBAR; 26.24 for SBBG; 21.37 for CFCV; 27.09 for CFAR and 29.51 for CFBG group. A significant increase in bond strength (p <0.05) was observed when Biosilicate® was used prior to the conventional and self-etching adhesive systems. Fracture pattern analysis by means of optical microscopy showed a predominance of mixed type fractures, with the exception of the CFCV group, where adhesive fractures predominated. It is concluded that arginine did not interfere with the bond strength with dentin, while the use of Biosilicate® tended to strengthen the bond between dentin and the adhesive systems used.