Physicochemical and biological properties of four calcium silicate-based endodontic cements.

Background/purpose: Several brands of calcium silicate-based cements (CSBCs) are currently marketed. Here we compared physicochemical and biological properties of new products Ortho MTA (BioMTA), Retro MTA (BioMTA), and EZ-Seal (Ezekiel) to widely used ProRoot MTA (Dentsply Tulsa). Materials and methods: CSBCs were analyzed by X-ray diffractometry and examined by scanning electron microscopy. Elemental composition was determined by energy dispersive spectroscopy. Particle size was measured by particle size analyzer. Human stem cells from apical papilla (SCAPs) were incubated with eluates from CSBCs. Survival of SCAP cells was evaluated with MTT assay. The Alizarin red S stain was used to identify calcified nodules formed in SCAP cultures. The effects of CSBC eluates on SCAP proliferation and migration were examined using an in-vitro scratch "wound-healing" assay. Results: All CSBC specimens showed similar X-ray diffraction patterns. The average particle size of EZ-Seal was smaller than ProRoot MTA, Ortho MTA, and Retro MTA (P < 0.001). The least cytotoxicity of eluates was found for EZ-Seal. In the Alizarin red S staining test, calcified nodules were observed in cultures with ProRoot MTA, Ortho MTA, and Retro MTA, however, no calcified nodules were observed in cultures with EZ-Seal. SCAP proliferation and migration capacity in presence of EZ-Seal was higher than with ProRoot MTA, Ortho MTA, and Retro MTA (P < 0.001). Conclusion: EZ-Seal has a smaller average particle size and a better cytocompatibility than all other examined CSBCs.

Cytokine Production and Cytotoxicity of Calcium Silicate-based Sealers in 2- and 3-dimensional Cell Culture Models.

INTRODUCTION: The aim of the present study was to assess the effects of different silicate-based sealers (ie, BioRoot RCS [Septodont, Saint Maur des Fosses, France], ProRoot ES [Dentsply Sirona, York, PA], and MTA Fillapex [Angelus, Londrina, PR, Brazil]) on cytokine production and viability of human periodontal ligament stem cells (PDLSCs). AH Plus (Dentsply DeTrey GmbH, Konstanz, Germany) was used as a reference material. METHODS: PDLSCs were cultured either in 2-dimensional or 3-dimensional conditions (in 0.15%-0.5% PuraMatrix [BD Biosciences, Bedford, MA]) for 24 hours with eluates from set endodontic sealers. Additionally, the toxicity of eluates from endodontic sealers was evaluated using an in vitro root model experimental procedure. PDLSC viability was determined using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. PDLSC culture medium was used for cytokine quantification (interleukin [IL]-6, IL-8, growth-regulated oncogene, IL,-4 and IL-10) using the HCYTMAG-60K-PX41 Milliplex kit (EMD Millipore, Burlington, MA). RESULTS: In 2-dimensional culture conditions, BioRoot RCS revealed a good PDLSC viability rate. ProRoot ES had no effect on PDLSC viability regardless of the dilution. MTA Fillapex was strongly cytotoxic even at the lowest extract dilutions (1:1, 1:2, and 1:4). Encapsulation of PDLSCs in PuraMatrix tended to decrease the cytotoxic effect of the sealers. In the 3-dimensional in vitro root model experimental procedure, BioRoot RCS, ProRoot ES, and MTA Fillapex revealed a cytocompatibility pattern. Different calcium silicate-based sealers exhibited different proinflammatory cytokine production. BioRoot RCS greatly stimulated the release of IL-10 and, to a lesser degree, IL-4 by PDLSCs (P < .05). CONCLUSIONS: BioRoot RCS and ProRoot ES did not induce proinflammatory cytokines and promoted anti-inflammatory cytokine secretion by PDLSCs that may have a positive local impact by attenuating an initial inflammatory response.

alpha7 integrin expressing human fetal myogenic progenitors have stem cell-like properties and are capable of osteogenic differentiation.

During muscle development, precursor cells fuse to form myofibers. Following injury in adult muscle, quiescent satellite cells become activated to regenerate muscle in a fashion similar to fetal development. Recent studies indicate that murine skeletal myoblasts can differentiate along multiple cell lineages including the osteoblastic pathway. However, little is known about the multipotency of human myogenic cells. Here, we isolate myogenic precursor cells from human fetal and adult muscle by sorting for the laminin-binding alpha7 integrin and demonstrate their differentiation potential and alteration in adhesive behavior. The alpha7-positive human fetal progenitors were efficient at forming myotubes and a majority expressed known muscle markers including M-cadherin and c-Met, but were heterogeneous for desmin and MyoD expression. To test their pluripotent differentiation potential, enriched populations of alpha7-positive fetal cells were subjected to inductive protocols. Although the myoblasts appeared committed to a muscle lineage, they could be converted to differentiate along the osteoblastic pathway in the presence of BMP-2. Interestingly, osteogenic cells showed altered adhesion and migratory activity that reflected growth factor-induced changes in integrin expression. These results indicate that alpha7-expressing fetal myoblasts are capable of differentiation to osteoblast lineage with a coordinated switch in integrin profiles and may represent a mechanism that promotes homing and recruitment of myogenic stem cells for tissue repair and remodeling.