Effect of Overlying Material on EndoCem Mineral Trioxide Aggregate Setting Reaction in Primary Molar Pulp

Purpose: To evaluate the impact of common restorative materials on the microhardness of ENDOCEM-MTA in primary molar pulpotomies. The study assessed whether the material placed over ENDOCEM-MTA affects its setting reaction, surface hardness, and uniformity across depths. Methods: Fifty extracted primary molars were prepared using standardized pulpotomy protocol. A 3mm layer of ENDOCEM-MTA was applied to the pulpal floor. Specimens were divided into five groups based on the overlying material: control (moistened cotton pellet), resin-modified glass ionomer cement (RMGIC, Fuji II LC), zinc oxide eugenol cement (IRM), RMGIC combined with a stainless-steel crown (SSC), and IRM combined with SSC. Teeth were incubated at 37°C and 100% humidity for 24 hours to simulate oral conditions. After incubation, specimens were sectioned, polished, and analyzed for microhardness using a Vickers Microhardness Tester at depths of 1mm, 2mm, and 3mm. Statistical analyses, including ANOVA and Tukey post hoc tests, were performed with significance set at P < 0.05. Results: All experimental groups performed as well as or better than the control, demonstrating clinical applicability. Group 4 (RMGIC with SSC) achieved the highest mean Vickers Hardness Number (VHN) of 72.66 ± 6.34 at 3mm depth, while the control group exhibited the lowest VHN (58.42 ± 11.26 at 1mm depth). Microhardness remained consistent across all depths, with significant differences observed between materials (P = .0009). Conclusions: Restorative materials significantly influenced the microhardness of ENDOCEM-MTA. RMGIC and IRM combined with SSC produced the most favorable outcomes, supporting their use in single-visit pulpotomies for improved procedural efficiency.