Evaluation of the Ca ion release, pH and surface apatite formation of a prototype tricalcium silicate cement

Abstract

Yamamoto S, Han L, Noiri Y, Okiji T. Evaluation of the Ca ion release, pH and surface apatite formation of a prototype tricalcium silicate cement. International Endodontic Journal, 50, e73-e82, 2017. Aim To evaluate the Ca 2+ -releasing, alkalizing and apatite-like surface precipitate-forming abilities of a prototype tricalcium silicate cement, which was mainly composed of synthetically prepared tricalcium silicate and zirconium oxide radiopacifier. Methodology The prototype tricalcium silicate cement, white ProRoot MTA (WMTA) and TheraCal LC (a light-cured resin-modified calcium silicate-filled material) were examined. The chemical compositions were analysed with a wavelength-dispersive X-ray spectroscopy electron probe microanalyser with an image observation function (SEM-EPMA). The pH and Ca 2+ concentrations of water in which the set materials had been immersed were measured, and the latter was assessed with the EDTA titration method. The surface precipitates formed on the materials immersed in phosphate-buffered saline (PBS) were analysed with SEM-EPMA and X-ray diffraction (XRD). Kruskal-Wallis tests followed by Mann-Whitney U-test with Bonferroni correction were used for statistical analysis (a = 0.05).Results The prototype cement contained Ca, Si and Zr as major elemental constituents, whereas it did not contain some metal elements that were detected in the other materials. The Ca 2+ concentrations and pH of the immersion water samples exhibited the following order: WMTA = prototype cement > TheraCal LC (P < 0.05). All three materials produced Ca-and P-containing surface precipitates after PBS immersion, and the precipitates produced by TheraCal LC displayed lower Ca/P ratios than those formed by the other materials. XRD peaks corresponding to hydroxyapatite were detected in the precipitates produced by the prototype cement and WMTA. Conclusion The prototype tricalcium silicate cement exhibited similar Ca 2+ -releasing, alkalizing and apatite-like precipitate-forming abilities to WMTA. The Ca 2+-releasing, alkalizing and apatite-like precipitate-forming abilities of TheraCal LC were lower than those of the other materials.

Bioactivity and biomineralization ability of calcium silicate‐based pulp‐capping materials after subcutaneous implantation

“…However, TheraCal LC formed smaller precipitates and significantly thinner Ca-and P-rich areas than the other materials. These findings are consistent with a recent laboratory study showing that Ca ion-releasing and apatite-like precipitate-forming abilities of TheraCal LC are lower than those of the other calcium silicate-based materials (Yamamoto et al 2017). This might be attributable to the fact that TheraCal LC is a resin-modified material in which ion exchange with the surrounding environment is limited.…”

“…Recently, a prototype tricalcium silicate cement (Nippon Shika Yakuhin, Shimonoseki, Japan; Table 1) has been developed, aiming at shortening the setting time, minimizing tooth discoloration and improving handling properties. This material is mainly composed of fine tricalcium silicate powder, which is prepared synthetically in the laboratory de novo, and zirconium oxide as a radiopacifier (Yamamoto et al 2017). The zirconium oxide has been demonstrated to act as an inert filler and not affect the hydration reaction of Portland cement .…”

TheraCal LC: From Biochemical and Bioactive Properties to Clinical Applications

“…TheraCal LC has displayed calcium release properties [ 6 , 20 – 23 ]. The bioavailability of calcium ions plays a key role in the material-induced proliferation and differentiation of human dental pulp cells and the new formation of mineralized hard tissues.…”

“…Camilleri et al [ 6 ] attributed the differences in the results due to the different methodologies used in each study. Moreover, Yamamoto et al [ 23 ] and that ProRoot MTA released significantly greater amounts of calcium ions than the TheraCal LC. The study also showed that TheraCal LC does not form calcium hydroxide after setting, although it releases calcium ions and produces calcium apatite on its surface.…”

Comparative analysis of the biological effects of the endodontic bioactive cements MTA‐Angelus, MTA Repair HP and NeoMTA Plus on human dental pulp stem cells

“…However, researchers have continued to focus on developing new MTA formulations to improve its physicochemical properties, without affecting its biocompatibility or bioactivity (Yamamoto et al . ).…”