<i>In Vitro</i> Evaluation of EndoCem Premix Mineral Trioxide Aggregate Microhardness in Primary Molar Pulpotomies.

<b>Purpose:</b> To evaluate the influence of commonly used restorative materials, including zinc oxide eugenol (ZOE), resin-modified glass ionomer cement (RMGIC) and stainless steel crowns (SSC), on the setting reaction (measured by microhardness) of Endo-Cem Premix Mineral Trioxide Aggregate (PMTA) when used as a pulpotomy agent. <b>Methods:</b> Fifty extracted primary molars had a pulpotomy with a three-millimeter layer of EndoCem PMTA applied to the pulpal floor. Specimens were divided into five groups: group one (control), EndoCem with a moistened cotton pellet; group two, EndoCem with RMGIC; group three, EndoCem with ZOE; group four, EndoCem with RMGIC and SSC; and group five, EndoCem with ZOE and SSC. Teeth were incubated at 37 degrees Celsius and 100 percent humidity for 24 hours. Microhardness was measured at depths of one, two and three millimeters using a Knoop hardness tester. Statistical analyses included analysis of variance and Tukey's post hoc tests (significance at P<0.05). <b>Results:</b> EndoCem PMTA demonstrated effective setting across all experimental groups, with an overall mean Knoop hardness number (KHN) of 65.71±9.98. Group four showed the highest mean KHN (72.66±6.34 at three mm), while the control had the lowest KHN (58.42±11.26 at one mm). Groups three and four had significantly higher KHN than the control group (P<0.01). Microhardness values remained consistent across depths, with the highest values observed at three millimeters. <b>Conclusions:</b> EndoCem PMTA sets reliably, regardless of the restorative material, supporting its application in single-visit pulpotomy procedures. The use of ZOE or RMGIC with SSC further enhanced its mechanical properties.