Sodium trimetaphosphate combined to calcium as a strategy to improve dentin-bonding interface

Abstract

Objective: The aim of this study was to evaluate the effect of STMP as biomimetic analog of dentin matrix onthe dentin bond strength submitted to artificial cariogenic challenge over time. Material and Methods: The totalnumber of teeth used in the experiment was 60 teeth, which were divided into 6 groups (n = 10). Of these totalamount, 10 teeth were not submitted to the artificial cariogenic challenge (ACC), serving as control group (SoundDentin - SD) while the other 50 were submitted to an ACC (7d/37ºC), being treated with treatment solutionsaccording to each group: SD- deionized water/sound dentin, CD- deionized water/ artificial caries dentin, GIIISTMP,GIV- STMP + Ca(OH)2, GV- STMP + NaF, and GVI- NaF. After treatments (24h), the specimens wererestored (Adper Single Bond Universal + Filtek Z250), to obtain resin–dentin sticks with a cross sectional area of0.8mm2, approximately. Two-third of these sticks were stored in artificial saliva (37°C) for analyzes after 6 and12 months. The 1/3 remains were subjected to mTBS test (baseline). Data were analyzed by two-way ANOVAand Tukey tests (p<0.05). Results: In general, the highest mTBS values were obtained in sound condition(SD), while the artificial caries condition (CD) determined minimum values. Groups treated with NaF (with orwithout STMP- GV and GVI) were not able to improve adhesion over time. Only the use of STMP + Ca(OH)2(GIV) improved the mTBS compared to the others caries-challenged dentin after 1 year. The adhesive failurepattern was predominant in all time. Conclusion: The use of the STMP associated with Ca(OH)2 seems to be aviable therapeutic strategy conciliating the biomimetizing capacity to the adhesive process satisfactorily even itsperformance is not superior to initial condition.KEYWORDSDentin; Dental adhesive; Protease inhibitors.