The effect of accelerated mineral trioxide aggregate on odontoblastic differentiation in dental pulp stem cell niches

Int Endod J. 2018 Jul;51(7):758-766. doi: 10.1111/iej.12747. Epub 2017 Feb 22.

Abstract

Aim: To investigate the effect of accelerated-set mineral trioxide aggregate (MTA) on the proliferation and odontoblastic differentiation of human dental pulp cell niches (DPSC).

Methodology: ProRoot White MTA (WMTA; Dentsply Tulsa Dental, Johnson City, TN, USA) was mixed with various additives, which included distilled water, 2.5% disodium hydrogen phosphate (Na2 HPO4 ; Merck, Darmstadt, Germany) and 5% calcium chloride (CaCl2 ; Merck). DPSC niches extracted from third molars were cultured directly on MTA in the culture medium. Cell viability was evaluated by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4- sulphophenyl)-2H-tetrazolium (MTS) assay. Cell growth and expression of odontoblastic differentiation markers (dentine sialophosphoprotein (DSPP) and collagen type 1 (COL1)) were determined using Real-Time Polymerase Chain Reaction analysis. Osteo-/odontogenic differentiation of DPSC niches was evaluated by measurement of alkaline phosphatase activity (ALP). Calcium deposition was assessed using von Kossa staining. The results were analysed statistically using Mann-Whitney tests and Kruskal-Wallis tests.

Results: MTA mixed with 5% CaCl2 and 2.5% Na2 HPO4 exhibited optimal cell viability (P < 0.05) compared to MTA mixed with distilled water. MTA mixed with 5% CaCl2 and 2.5% Na2 HPO4 significantly increased ALP activity (P < 0.05), significantly promoted mineralization nodule formation (P < 0.05) and significantly enhanced the mRNA expression level of the osteogenic/odontogenic markers (P < 0.05; DSPP and COL1) compared with MTA mixed with distilled water.

Conclusions: MTA mixed with 5% CaCl2 and 2.5% Na2 HPO4 was biocompatible with dental pulp stem cell niches. Accelerated-set MTA promoted better differentiation in DPSC niches than conventional MTA. The accelerators could provide an alternative to MTA mixed with distilled water.

Keywords: MTA; accelerators; biocompatibility; dental pulp stem cell niche; odontoblastic differentiation.

MeSH terms

  • Adolescent
  • Aluminum Compounds / pharmacology*
  • Calcium Compounds / pharmacology*
  • Cell Differentiation / drug effects
  • Cell Proliferation / drug effects
  • Cells, Cultured
  • Collagen Type I / metabolism
  • Dental Pulp / cytology*
  • Dental Pulp / drug effects
  • Drug Combinations
  • Humans
  • Odontoblasts / drug effects*
  • Odontogenesis / drug effects
  • Oxides / pharmacology*
  • Real-Time Polymerase Chain Reaction
  • Root Canal Filling Materials / pharmacology
  • Silicates / pharmacology*
  • Stem Cell Niche / drug effects*
  • Stem Cells / drug effects

Substances

  • Aluminum Compounds
  • Calcium Compounds
  • Collagen Type I
  • Drug Combinations
  • Oxides
  • ProRoot MTA
  • Root Canal Filling Materials
  • Silicates
  • mineral trioxide aggregate