Examination of surface porosity of current pulp capping materials by micro-computed tomography (micro-CT) method

When dental pulp is exposed, it must be covered with a biocompatible material to form reparative dentine. The material used, besides being biocompatible, should have an ideal surface structure for the attachment, proliferation and differentiation of dental pulp stem cells. This study aimed to evaluate the porosity of the microstructures of four pulp capping materials using micro-computed tomography (micro-CT). Biodentine, Bioaggregate, TheraCal and Dycal materials were prepared according to the manufacturer's instructions using 2 × 9 mm Teflon molds. A total of 60 samples, 15 in each group, were scanned using micro-CT. Open and closed pores and the total porosity of the microstructures of the materials were assessed. The findings obtained from the study were analyzed via the Kruskal-Wallis test followed by the Mann-Whitney U test. The porosity of Bioaggregate was significantly higher than that of Biodentine, Dycal and TheraCal in all porosity values. While Biodentine did not show a statistically significant difference in open and total porosity values from either TheraCal or Dycal, closed porosity values of Dycal were significantly higher than those of Biodentine and TheraCal. Because of the affinity of cells to porous surfaces, the pulp capping materials' microstructure may affect the pulp capping treatment's success. From this perspective, the use of Bioaggregate in direct pulp capping may increase the success of treatment.