Higher hydration performance and bioactive response of the new endodontic bioactive cement MTA HP repair compared with ProRoot MTA white and NeoMTA plus

Abstract

The aim of this study was to characterize the hydration performance and the bioactive response of the new bioactive endodontic cement MTA HP repair (HP), comparing its physicochemical parameters with those of ProRoot MTA White (Pro) and NeoMTA Plus (Neo). Un-hydrated precursor materials were characterized by X-ray fluorescence, laser diffraction, N 2 physisorption and field emission gun scanning electron microscopy (FEG-SEM). Setting time was assessed according to ASTM specification C 266. Hydrated materials were analyzed by X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR) and (FEG-SEM). Bioactivity evaluation in vitro was carried out, by soaking processed cement disk in simulated body fluid (SBF) during 168 h. The cements surface was studied by FT-IR, FEG-SEM, and energy dispersive X-ray. Release to the SBF media of ionic degradation products was monitored using inductively coupled plasma atomic emission spectroscopy. HP showed shorter initial setting time compared to Pro and Neo and produce a quick and effective bioactive response in vitro in terms of phosphate phase surface coating formation. This higher bioactive response for HP is correlated with increasing calcium aluminate content, increasing surface area of un-hydrated powder precursor and the increasing release capacity of Si ionic products of the final hydrated product. The higher bioactive response of MTA HP repair highlights this material, as very interesting to further investigate its performance to improve the outcome of vital pulp therapy procedures.

A Microstructure Insight of MTA Repair HP of Rapid Setting Capacity and Bioactive Response

“…EDX analysis after SBF treatment indicates that Si energy peak intensity does not decrease in intensity with CaP coating progressing from 24 to 72 h time treatment (Figure 7). These results, in addition to the previous analysis in similar conditions of Si and Ca ionic products release [21], are consistent with further silica-rich layer repolymerization through silanol group's condensation from the soluble silica.…”

“…Electron microscopy analysis of the precursor powder consisting of Ca 3 SiO 5 , Cal 2 SiO 4 , Ca 3 Al 2 O 6 , and radiopacifier component, CaWO 4 , indicates singular sub-micron particle size showing predominantly elongated shape. In relation to this particle size, the relatively low intensity XRD peaks detected for the calcium silicate species of the material in comparison with other calcium silicate cements [21], correlates well with the sub-micron particle sizes observed by FEG-SEM and TEM. The bright field observations using TEM in combination with EDX analysis determined that characteristic MTA Repair HP nanoparticles exhibiting, low contrast imaging, as well as faceted singularity and elongated morphology, do not contain aluminum, indicating that these geometrically regular nanoparticles correspond to a calcium silicate phase.…”

“…Previous work, comparing MTA Repair HP physicochemical parameters with those of ProRoot MTA White and NeoMTA Plus, carried out by our group has reported HP distinctive physicochemical parameters [21]. Particularly, un-hydrated MTA Repair HP in the powder form shows characteristic elongated nanoparticles within 50-100 nm range size thickness [22], which we associate to the high BET surface area of 4.8 m 2 g −1 for this material.…”

“…MTA Repair HP dental material is endodontic cement, which shows both a rapid setting rate of 12 min (initial setting time) [21], and a quick and effective bioactive response in vitro in terms of surface coating of calcium phosphate [19]. In this work, a detailed look at the material microstructure highlights particular characteristics to understand these interesting properties.…”

The Effectiveness of Laser-Activated Irrigation on the Apical Microleakage Qualities of MTA Repair HP and NeoMTA Plus in Simulated Immature Teeth: A Comparative Study

“…The differences observed between two tested BEC S could be attributed to the physicochemical formulation of MTA Repair HP. The addition of a polymer plasticizer to the liquid structure of MTA Repair HP provides a better putty and homogeneous compositions that increase fluidity during manipulation procedures.Moreover, the low initial setting time of MTA Repair HP may lead to variations by increasing the effective biological responses of hydroxyapatite surfaces and creating hydrated gel forms to fill spaces between calcium silicate particles [ 33 , 34 ]. Hence, the short-term findings of the present study between MTA Repair HP and NeoMTA Plus are supported.…”