The effect of mixing method on tricalcium silicate‐based cement

Abstract

DuqueJA, Fernandes SL, Bubola JP, Duarte MAH, Camilleri J, Marciano MA. The effect of mixing method on tricalcium silicate-based cement.International Endodontic Journal, 51, 69-78, 2018. Aim To evaluate the effect of three methods of mixing on the physical and chemical properties of tricalcium silicate-based cements. Methodology The materials evaluated were MTA Angelus and Portland cement with 20% zirconium oxide (PC-20-Zr). The cements were mixed using a 3 : 1 powder-to-liquid ratio. The mixing methods were manual (m), trituration (tr) and ultrasonic (us) activation. The materials were characterized by means of scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy. Flowability was analysed according to ANSI/ADA 57/2012. Initial and final setting times were assessed following ASTM C266/08. Volume change was evaluated using a micro-CT volumetric method. Solubility was analysed according to ADA 57/2012. pH and calcium ion release were measured after 3, 24, 72 and 168 h. Statistical analysis was performed using two-way analysis of variance. The level of significance was set at P = 0.05. Results The SEM analysis revealed that ultrasonic activation was associated with a homogeneous distribution of particles. Flowability, volume change and initial setting time were not influenced by the mixing method (P > 0.05). Solubility was influenced by the mixing method (P < 0.05). For pH, at 168 h, significant differences were found between MTA-m and PC-20-Zr-m (P < 0.05). For calcium ion release, PC-20-Zr-tr had higher values than MTA-m at 3 h, and MTA-tr had higher values than PC-20-Zr-m at 168 h (P < 0.05). Conclusions The ultrasonic and trituration methods led to higher calcium ion release and pH compared with manual mixing for all cements, whilst the ultrasonic method produced smaller particles for the PC-20-Zr cement. Flow, setting times and volume change were not influenced by the mixing method used; however, it did have an impact on solubility.

Tricalcium silicate-based cements: properties and modifications

“…9,10,11 The physical, chemical, and biological properties of MTA have been studied for decades and novel substances were eventually introduced, but improvements are still required to obtain an ideal composition. 12,13,14 A perfect endodontic restorative material should present physical characteristics such as sealing, dimensional 15 and color stability, 16,17 radiopacity, 18,19 insolubility in contact with fluids, 20,21 flowability, and easy insertion; 22,23 and also chemical and biological properties such as alkaline pH, release of calcium ions, 24 bioactivity, 25 cell attachment, 26 and biocompatibility. 27 Declaration of Interests: The authors certify that they have no commercial or associative interest that represents a conflict of interest in connection with the manuscript.…”

WITHDRAWN: Alkalizing properties of new calcium-silicate endodontic biomaterials

“…These materials have also physical properties suitable for their clinical use, such as good sealing [12,13], dimensional stability [14], insolubility in contact with body fluids [15,16], flowability, and easy manipulation/insertion [17,18]. Therefore, new calcium silicate MTA-like cements have been lately introduced.…”

Evaluation of the bioactivity of fluoride‐enriched mineral trioxide aggregate on osteoblasts

“…For biomechanical sensing, osteoblasts seize the elasticity and topology of MTA by anchoring to the cement via focal adhesion sites (Giancotti & Ruoslahti 1999, Fletcher & Mullins 2010, which facilitate the reciprocal transformation of biomechanical to biochemical signals (Tomakidi et al 2014). Generally, the physical properties of solidified MTA largely rely on handling parameters such as powder/liquid ratio (Basturk et al 2015), mixing method (Nekoofar et al 2010, Basturk et al 2014, Duque et al 2018, condensation pressure (Nekoofar et al 2007), environmental humidity (Caronna et al 2014, Shokouhinejad et al 2014) and pH (Bolhari et al 2014), all being constant in the experimental set-up. From a chemical viewpoint, mixing the MTA powder with fluoride-enriched water is assumed to result in chemical integration of fluoride into the solidifying crystal structures (Song et al 2006, Parirokh & Torabinejad 2010a, which probably sustains physical characteristics similar to nonfluoride ProRoot MTA (Appelbaum et al 2012).…”