Objective: The aim was to evaluate MTA PlusTM material’s properties, namely calcium release, the pH change, solubility, water sorption, porosity, surface morphology and apatite-forming ability after immersion in simulated body fluid.
Method: Two tricalcium silicate powders (MTA PlusTM, ProRoot® MTA) and Dycal® were tested. After incubation at 37°C and 99% relative humidity the calcium and hydroxyl ion release were tested up to 28 days in deionized water at 37°C. Water absorption, interconnected pores, apparent porosity and solubility were measured after 24 hr immersion in deionized water at 37°C. The morphological and elemental analysis of the materials’ surfaces were examined using ESEM/EDX after storage at 37°C for 1 to 28 days in simulated body fluid (SBF) using the ISO 23317 method.
Results: All 3 materials created an alkaline pH within 3 hours, which continued for 28 days. MTA Plus had higher ion release than ProRoot MTA and Dycal; the use of the MTA Plus gel enhanced the initial calcium release and the increase of the pH. Both MTA materials were more porous, water-soluble and water-sorptive than Dycal, but also more bioactive. After aging in SBF, MTA Plus material caused precipitation of an apparent calcium phosphate layer.
Conclusions: MTA Plus showed an improved reactivity and prolonged capability to release calcium and increase the local pH to alkaline values in comparison with ProRoot MTA. These pronounced ion-releasing properties are interlinked with its noticeable porosity, water sorption and solubility and with the formation of CaP minerals. The finer calcium silicate powder may explain the higher ion release, water sorption, porosity and solubility of MTA Plus compared to ProRoot MTA.For clinicians MTA Plus represents a lower cost bioactive tricalcium silicate material with interesting chemical-physical properties that could be a convenient alternative to the conventional calcium silicate MTA-like cements.