The influence of differents desensitizing agents on dentin hydraulic conductivity and bond strength of a resin cement used to luting indirect restorations

Abstract

Pos operatory sensitivity is a frequent symptom in dentistry or prosthesis procedures, especially after crown preparation. This undesiderable sign can be justified and better understood by the Hydrodynamic Theory, which is based on the fluid movements through the lumen of the dentinal tubes. Based on this Theory, some chemical substances were developed to obstruct the dentinal tubes and then reduce or stop dentinal fluid. Purpose: The present study has the objective to evaluate the influence of different dentin desensitizer agents on the hydraulic conductance (measured as proposed by PASHLEY and GALLOWAY, 1985) and on the dentin bond strength (by the microtensile bond strength test) of a resin cement used to luting indirect restoration. Four different groups will be evaluated: G1: Sensi Kill (DFL, Rio de Janeiro, Brasil); G2: BisBlock (BISCO, Schaumburg, EUA); G3: Experimental gel; G4 (Control group): no treatment. The hydraulic conductance measurements will be analyzed before and after the application of the dentin desensitizer agents. Subsequently, each think dentin discs will receive the application of total each adhesive system Adper™ Single Bond 2 (3M ESPE, St. Paul, EUA) and then restored with the resin cement Rely XTM ARC (3M ESPE, St. Paul, EUA) and a composite block, previously made in order to simulate an indirect restoration. Statistical Analyses: dentin hydraulic conductance measurements will be analyses by Two-way ANOVA. Microtensile bond strength data will be independently analyzed by One-way ANOVA. Correlation test between the two trials (hydraulic conductance and bond strength) will be performed by the Spearman test. In all the statistics analyses significant level will set at alpha=5%. (AU)