Effect of endodontic sealers on pH of the medium in which they are immersed

Abstract

INTRODUCTION: The endodontic sealers are essential for three-dimensional root canal obturation. The sealers are based on epoxy resin, AH Plus and bioceramic sealers, Bio-C Sealer and BioRoot RCS, which are bioactive materials due to the ability to cause a specific biologic reaction in integration with the receptor tissue, with a pH of 12,5. OBJECTIVE: To evaluate in vitro, the capacity of different endodontic sealers to modify the pH of the solution in which they are immersed, at different time. MATERIALS AND METHODS: Fifteen samples of sealers were prepared and placed into holes of blister packs, which set for 24 hours in store at 37 degrees Celsius. Then, each sample was immersed in sterile plastic bottles with 30 millimeters of physiological solution. Samples were divided into three groups(n=5) according to the sealer: 1) BioRoot RCS, 2) Bio-C Sealer and 3) AHPlus. The pH measurements were performed in different periods of time with a digital pH meter: immediate, 40 min, 24 and 48 hs, 7, 14, 21 and 30 days. Data were made by means of the Variance Analysis Test with repeated measurements. RESULTS: The pH of AH Plus did not change during the experience. At 24 hs, both bioceramic sealers increased medium pH up to alkaline value, which was maintained with BioRoot sealer (mean 11,54) until 30 days. At 7 days, the pH of the medium with Bio-C Sealer started decreasing. Evolution of sealers pH along the time revealed statistical significant difference (p<0,001). CONCLUSION: AH Plus sealer did not modifie the pH of the medium Both bioceramic sealers increased the pH, reaching to the maximum alkaline value at 7 days, which was maintained with BioRoot RCS and lightly decreased with Bio-C Sealer at 30 days.