Effects of mineral trioxide aggregate on the osteogenesis of normal human osteoblasts

Date
2003
DOI
Authors
Mehrabi, Amir H.
Version
OA Version
Citation
Abstract
A novel material, Mineral trioxide aggregate (MTA) has been used in endodontics for sealing the roots of teeth and has been reported to produce biological response. Many studies have been done on biocompatibility and cytotoxicity of this material. However, there are many unidentified factors in the response of various cells, such as osteoblasts to MTA. In this in vitro study, effects of MTA on cell attachment efficiency, cell proliferation, osteocalcin expression and alkaline phosphatase (ALP) activity of human osteoblasts were tested. Human osteoblast-like cells, derived from healthy alveolar bone were used for all of the experiments in this study. All of the experiments were performed using cells from second passage. Cells in the experimental, MTA group and controls were cultured in Dulbecco’s Modified Eagle Medium (DMEM) supplemented with F-12 nutrient mixture, fetal bovine serum (FBS), penicillin G (5000 U/ml)/streptomycin sulfate (5000 [mu]g/ml), and 250 [mu]g/ml Amphotericin B. Cells were cultured for periods of 12 and 20 days. MTA was mixed according to manufacturer’s instructions, and made into discs of ~0.5 mm thickness in a cuIture hood, and maintained in 37[degrees]C, 5% Co2 and 1OO% humidity and allowed to set for 24 hours. Differentiation medium, culture medium supplemented with Vit. D3, was used for all culture for 48 hours. Cells were screened for osteoblast phenotype prior to all experiments. The pH changes in the culture medium was observed and recorded. Cell attachment efficiency and proliferation were determined by measuring the optical density of crystal violet dye in fixed culture cells. ALP activity was determined by measuring optical density of released p-Nitrophenol in extracted culture media. Osteocalcin expression was determined by measuring [125]l-labeled antibody in extracted culture media. All data were normalized on per 10[5] ceils basis and a two sample t-test assuming equal variances was used for statistical analysis. Mean pH value of culture medium increased during culture period, cell attachment efficiency was significantly higher in cells cultured in presence of MTA (p[less than]0.0001). Cell proliferation rate was significantly higher in MTA group (p[less than]0.0001) after 12 day of culture. There were significantly higher number of cells in presence of MTA both at 12 and 20 days (p[less than]0.001), ALP activity of cells in presence of MTA was significantly higher than control at 12 days (p[less than]0.05). However, cells in the control exhibited significantly higher osteocalcin expression at 12 days (p[less than]0.01). Based on the results of this in vitro study, MTA is capable of stimulating some osteogenic effects in normal osteoblast-like cultures. Further studies needed to evaluate exact mechanism of action of this material on osteoblasts.
Description
Thesis (M.S.D.)--Boston University, Henry M. Goldman School Dental Medicine, 2003 (Endodontics).
Includes bibliography (leaves 88-100).
License
This work is being made available in OpenBU by permission of its author, and is available for research purposes only. All rights are reserved to the author.