Effect of Varying Water-to-Powder Ratios on Compressive Strength and Porosity of Mineral Trioxide Aggregate

摘要

The proportion of MTA powder and water is a common factor impacted on the properties of the material in clinical application. The purpose of this research was to determine the compressive strength and porosity of Mineral Trioxide Aggregate (MTA) mixed with varying water-to-powder (WP) ratios. ROOTDENT MTA was investigated. One gram of cement was mixed with 0.28, 0.33 or 0.40 grams of distilled water and was submerged either for 1, 7, or 28 days in the water. The chemical composition of un-hydrated MTA was characterized by X-ray fluorescence. Samples were carried out for compression and porosity test. ROOTDENT MTA was composed primarily of calcium, oxygen, and zirconium. Minor quantities of sodium, aluminum, and silicon were presented in the cement and lack of bismuth was found. The highest mean compressive strength value was MTA with 0.33 WP ratio submerged in the water for 28 days. The percentage of porosity increased as the WP ratio increased. The percentage of porosity submerged in the water for 7 and 28 days showed no significant differences while the lowest porosity was MTA with 1 day in the water.