A COMPARATIVE STUDY OF THE EFFECT OF PBS ON MTA HARDNESS WHEN USED AS A MIXING SOLUTION

Abstract

Aim: This in vitro research aimed to evaluate and contrast the hardness measurements of MTA mixed with water and MTA mixed with phosphate-buffered saline (PBS), after a 28-day incubation period. Methodology: A 5 mm length section was obtained from each tooth at the cemento-enamel junction using a microslicer (MicroSlice 2 Precision Slicing Machine, Malvern Instrument, UK). All sections were shaped with the largest diamond bur, 2 mm wide. The samples were encased in a resin block for simpler handling. The specimens were then divided randomly into two groups (n = 19), based on the mixing solution used. The first group comprised an MTA 5 mm apical plug mixed with PBS. The second group involved an MTA 5 mm apical plug mixed with water. These specimens were incubated for 28 days at 37°C and 100% humidity. The assessment of surface microhardness was conducted using the Vickers microhardness test (VHN) with a 9.8 N load. Data were analysed using the Statistical Package for Social Science version 20.0 (SPSS Inc., Chicago, IL, USA). The level of significance was established at P<0.05. Results: The mean and standard deviation of the microhardness for the MTA mixed with PBS were higher (114.57 ± 65.44) compared to those for the MTA mixed with water (65.39 ± 12.6). There was a statistically significant difference observed between the two groups (t (19.33) = 3.216, p =0.004, Cohen’s d = 1.043). Conclusion: The surface VHN of MTA mixed with PBS was significantly higher compared to MTA mixed with water.