Cytotoxicity and Alkaline Phosphatase Activity Evaluation of EndoSequence Root Repair Material

Introduction: The purpose of this in vitro study was to evaluate the cytotoxicity and alkaline phosphatase (ALP) activity of a new bioceramic root repair material, Endo Sequence Root Repair Material (ESRRM; Brasseler USA, Savannah, GA), and to compare these characteristics with those of Pro Root MTA (Dentsply Tulsa Dental, Tulsa, OK) and Geristore (GR; Den-Mat LLC, Santa Maria, CA). Methods: Human Saos-2 osteoblast-like cells were exposed to 1-, 3-, and 7-day elutes of the materials (100% and 50% strength) for 24 hours after which the bioactivity and ALP activity of the cells were evaluated using a methylthiazol sulfophenyl (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)- 2H-tetrazolium) assay and para-Nitrophenylphosphate colorimetric assay, respectively. In the positive control group, Triton X-100 (Boehringer Mannheim Corp, Indianapolis, IN) was used to lyse the cells, representing 100% cytotoxicity, and in the negative control group cells received fresh culture medium only. Data were statistically analyzed using the unpaired t test and 1-way analysis of variance. Results: The results revealed that the bioactivity of the cells as well as ALP activity were significantly decreased after exposure to ESRRM elutes in almost all time periods, both in 100% and 50% concentrations, with the exception of ALP activity of day 1 elutes of ESRRM at 50% concentration. MTA did not change the bioactivity or ALP activity of the cells. GR elutes of 100% concentration reduced the bioactivity on days 1 and 3, whereas GR elutes of 50% concentration affected the cells only on day 1. None of the GR elutes had any effect on ALP activity of the cells. Conclusions: It was concluded that ESRRM elutes of all time periods in general reduced the bioactivity and ALP activity of osteoblast-like cells. GR reduced bioactivity only, whereas MTA had no effect on the cells. (J Endod 2012;38:1101-1105)