L M Formosa1, B Mallia, J Camilleri. 1. Department of Metallurgy and Materials Engineering, Faculty of Engineering, University of Malta, Malta.
Abstract
OBJECTIVE: One of the problems encountered clinically when using mineral trioxide aggregate (MTA) as a root-end filling material is washout immediately after placement. A novel MTA is supplied with an anti-washout gel that replaces the mixing water. The aim of this research was to characterize and assess the properties of a novel MTA mixed with an anti-washout liquid. METHODS: MTA Plus mixed with either water (MTA-W) or an anti-washout gel (MTA-AW) was investigated. Un-hydrated and set materials were characterized by scanning electron microscopy (SEM), energy X-ray dispersive analysis (EDX), X-ray diffraction analysis (XRD) and Fourier transform infrared spectroscopy (FT-IR) after being stored dry or immersed in Hank's balanced salt solution (HBSS). The chemical and physical properties of the set materials were then investigated. RESULTS: The MTA Plus was composed of tricalcium silicate, dicalcium silicate and bismuth oxide. The anti-washout gel used was water-based and FT-IR plots showed the presence of an organic additive. Both materials immersed in HBSS displayed the presence of reaction by-product with MTA-W exhibiting a high-intensity calcium hydroxide peak on X-ray diffraction. The X-ray diffractograms of all materials following hydration demonstrated the reduction in peak intensity of the tri- and dicalcium silicate. Hydroxyapatite deposits were evident on the surfaces of both materials in contact with HBSS. The pH of the leachate was similar for both materials. MTA-AW exhibited lower levels of calcium ions in solution and reduced fluid uptake in the early stages of reaction. The anti-washout gel reduced the setting time of the cement and enhanced the compressive strength. The radiopacity of both materials was approximately 8mm aluminum. SIGNIFICANCE: The use of the water-based anti-washout material instead of the standard water with MTA affects the hydration and properties of the set material.
OBJECTIVE: One of the problems encountered clinically when using mineral trioxide aggregate (MTA) as a root-end filling material is washout immediately after placement. A novel MTA is supplied with an anti-washout gel that replaces the mixing water. The aim of this research was to characterize and assess the properties of a novel MTA mixed with an anti-washout liquid. METHODS: MTA Plus mixed with either water (MTA-W) or an anti-washout gel (MTA-AW) was investigated. Un-hydrated and set materials were characterized by scanning electron microscopy (SEM), energy X-ray dispersive analysis (EDX), X-ray diffraction analysis (XRD) and Fourier transform infrared spectroscopy (FT-IR) after being stored dry or immersed in Hank's balanced salt solution (HBSS). The chemical and physical properties of the set materials were then investigated. RESULTS: The MTA Plus was composed of tricalcium silicate, dicalcium silicate and bismuth oxide. The anti-washout gel used was water-based and FT-IR plots showed the presence of an organic additive. Both materials immersed in HBSS displayed the presence of reaction by-product with MTA-W exhibiting a high-intensity calcium hydroxide peak on X-ray diffraction. The X-ray diffractograms of all materials following hydration demonstrated the reduction in peak intensity of the tri- and dicalcium silicate. Hydroxyapatite deposits were evident on the surfaces of both materials in contact with HBSS. The pH of the leachate was similar for both materials. MTA-AW exhibited lower levels of calcium ions in solution and reduced fluid uptake in the early stages of reaction. The anti-washout gel reduced the setting time of the cement and enhanced the compressive strength. The radiopacity of both materials was approximately 8mm aluminum. SIGNIFICANCE: The use of the water-based anti-washout material instead of the standard water with MTA affects the hydration and properties of the set material.