Evaluation of physical, biological and mechanical properties of experimentally developed contemporary dental pulp capping materials in in vitro conditions

Aim: In cases where the pulp is exposed, it is important to cover the pulp surface with a biocompatible, physically and mechanically sufficient material. In this study, it is aimed to evaluate the biological, physical and mechanical properties of frequently used and experimentally developed pulp capping materials in vitro. Material and Method: A homogeneous mixture was obtained by adding + 0.1% GNP (graphene nanoplatelet) and + 0.3% GNP (graphene nanoplatelet) to Angelus MTA and these groups formed the experimental group of the study. Angelus MTA and Dycal were used as control groups. The materials were mixed according to the manufacturer's instructions and disc-shaped specimens were formed in teflon molds. The microhardness, SEM-EDX, XRD and FTIR analyzes of the materials and 24-hour and 72-hour MTT, TAS and TOS tests on gingival fibroblast cells were performed in vitro. Results were evaluated statistically by using SPSS software. Results: A significant difference was found between the control group and Angelus MTA + 0.3% GNP in 24 and 72 hours MTT analysis (p <0.05) and 24-hour Dycal (p = 0.001) and 72-hour MTT analysis (p = 0.002). A significant difference was also found between Dycal and Angelus MTA + 0.3% GNP groups at TOS 72., TAS 24th and 72th hours and Dycal and control group at TOS 24 hours (p <0.05). The addition of GNP did not make a significant difference in FTIR analysis. GNP did not yield a peak in XRD analysis. As the amount of GNP doping increased, microhardness increased and particle size decreased. It is evidenced by a SEM image, where the particle size decreases and the hollow structure diminishes. In the EDX analysis, the effect of GNP was observed with an increase in carbon content. Conclusion: While the addition of GNP to MTA contributed positively to physical, mechanical properties due to increase in quantity, it reduced the biocompatibility of the material. Keywords: Angelus MTA, Dycal, graphene nanoplatelet, pulp capping, cytotoxicity.