Comparison of Shear Bond Strength of Silorane and Nanohybrid Composite Resins to Calcium Enriched Mixture Cement in Different Time Periods

Statement of problem: It is crucial to select the best dental material forrestoration of teeth that undergo vital pulp therapy after endodontic treatment.Objectives: Adhesion of composite resin and endodontic pulp cappingmaterial affect the outcome of treatment. The aim of the present study is toevaluate the adhesion of two different composite resins to calcium enrichedmixture (CEM).Materials and Methods: We prepared a total of 60 cylindrical acrylicblocks that contained a central hole (4 mm diameter and 2 mm height).CEM cement was mixed according to the manufacturer’s instructionsand introduced into the holes. We stored 30 specimens for 3 days and theremaining 30 specimens were stored for 7 days at 37ºC. The specimens werefurther divided into 2 subgroups based on the composite resins that we used.One subgroup of specimens was restored by Z350 (3M, ESP, St. Paul, MN,USA) nanohybrid and the other restored by P90 (3M, ESP, St. Paul, MN,USA) silorane based composite. Shear bond strengths were measured by auniversal testing machine. Failure modes of the samples were evaluated undera stereomicroscope.Results: At day 3, P90 had significantly higher shear bond strength thanZ350 (P=0.001). On day 7, Z350 had significantly higher shear bond strengthcompared to P90 (P=0.004).Conclusions: Within the limits of the present study, the best results of P90silorane based composite filling after vital pulp therapy with CEM cementbiomaterial were obtained after 3 days, whereas the Z350 nanohybridcomposite showed better results on day 7.