Bond Strength of a GPDM-Based Self-Adhesive Cement Compared to Conventional Resin Cements on 3D-Printed Crown Material

Background: The clinical success of 3D-printed permanent restorations depends on the bond durability between the restorative material and resin cements. Comparative data on the performance of conventional and self-adhesive cements on these substrates after aging are limited. The purpose of this in vitro study was to evaluate the shear bond strength (SBS) and microtensile bond strength (µTBS) of four resin cements to a 3D-printed permanent crown material. Methodology: The shapes of the restorative material used in the study were virtually created with dentalCAD software. For SBS test four circular cement layers were formed on each disc with a 3 mm diameter and 2 mm high transparent silicone index, each polymerized for 20 seconds, resulting in a total of 28 cement layers per group and 112 layers in total. For the SBS tester speed is set to 1 mm/s and for the µTBS test the tester is set to 0.5 mm/s. Fracture surfaces were examined with an electron microscope and stereomicroscope classified into three types; adhesive, mix, and cohesive. One-way ANOVA and Tukey HSD as a post-hoc test were used for statistical analysis. Result: According to the Post-Hoc Tukey HSD test, significant differences were found between the adhesive resin cements for the SBS and µTBS (p<0.05). According to Levene's test and post-hoc Kolmogorov-Smirnov test, there is a statistically significant difference in fracture types (p<0.05). Conclusion: According to the results, Nova Resin resin cement showed the highest bond value for SBS. For µTBS value, Nova Resin cement showed the lowest value among the groups.