Bond Strength to Dentin after Self-limiting Caries Therapy

Objectives: Self-limiting caries therapy methods try to maintain as much tooth tissue as possible. However, for durable restorations the interface to the remaining less mineralized dentin should be strong enough to resist fatigue forces until the potential remineralization stabilizes the remaining tissue.

Methods: Two different treatment groups were investigated. Carisolv Single Mix was compared to a prototype enzyme solution SFC-V with the microtensile test. To evaluate the influence of the solutions both groups were applied with a plastic instrument which is not in accordance with the manufacturer's recommendations for Carisolv. Both groups were applied to sound and carious dentin. The tooth surface was restored with SyntacClassic and TetricEvoCeram (both Vivadent, Schaan, FL). After 24 h water storage at 37° C 1 x 1 mm dentin sticks were cut and subjected to the tensile test. 20 specimen were evaluated in each group. The statistical analysis included 2factorial ANOVA and Weibull analysis.

Results: The mean tensile strength, standard deviation, the corresponding Weibull modulus m and Sigma50 s50 are summarized in the table (sd = sound dentin, cd = carious dentin, e = enzyme, c = Carisolv):

The mean microtensile strength of the enzyme group was significantly higher in both dentin qualities. In either group carious dentin had significantly lower values.

Conclusions: The tensile strength to carious dentin was significantly lower in both treatment groups, however, the order of magnitude is comparable to the “sound dentin” group of Carisolv, which is clinically already well established. Further test have to demonstrate whether the tensile strength is high enough for durable restorations.