Effect of pH on Sealing Ability of White Mineral Trioxide Aggregate as a Root-end Filling Material

The aim of the present study was to evaluate microleakage of mineral trioxide aggregate (MTA) used as a root-end filling material after its exposure to a range of acidic environments during hydration. Seventy single-rooted teeth were divided into 4 experimental and 2 control groups. All the teeth were instrumented, and their apices were resected. Root-end cavities were filled with white MTA in the experimental groups. In the control groups root-end cavities were not filled. Root-end fillings were exposed to acidic environments with pH values of 4.4, 5.4, 6.4, or 7.4 for 3 days in the experimental groups. Microleakage was evaluated by using bovine serum albumin. The evaluation was conducted at 24-hour intervals for 80 days. Data were analyzed by using one-way analysis of variance and a post hoc Tukey test. The earliest bovine serum albumin microleakage was observed in a pH value of 4.4 followed by pH values of 5.4, 6.4, and 7.4, respectively. There was a significantly longer time necessary for leakage to occur in samples stored in higher pH values (P < .000).