Effect of adding disodium hydrogen phosphate to white mineral trioxide aggregate on compressive strength

Abstract

The delayed setting time of mineral trioxide aggregate is on of its disadvantages. Various materials have been added to MTA to decrease its setting time. Adding Na2Hpo4 to WMTA increases biocompatibility and decreases the setting time; but its effect on the compressive strength of WMTA has not been assessed yet. So, this study aimed to evaluate the compressive strength of WMTA and Na2Hpo4 mixture. Materials & Methods: 30 WMTA and 30 WMTA + Na2Hpo4 mixture were prepared. Each group was divided to 2 subgroups randomly, and their compressive strength at 21 hours and 21 days after preparation. On-way ANOVA test was utilized for determining the significancy of differences between groups. The comparison between two groups was performed using Tukey test at 0.05 level of significancy. Results: Mean standard deviation of experimental groups, WMTA at 21 hours, WMTA at 21 days, WMTA+ Na2Hpo4 at 21 hours, and WMTA+ Na2Hpo4 at 21 days, were 12061, 25994, 12440, and 20160, respectively. One-way ANOVA analysis indicated that the difference between groups is significant (P<0.001). Tukey post hoc test showed that there was not any significant difference between WMTA and WMTA+ Na2Hpo4 at 21 days (P=0.055). There was not any significant difference between 21 days groups (P=0.998). However, difference between 21 hours and 21 days groups was significant in both of sample groups (P<0.05). Conclusions: Based on this studies findings, adding Na2Hpo4 to WMTA did not decrease the compressive strength.