Josette Camilleri1. 1. Department of Building and Civil Engineering, University of Malta, Malta. josette.camilleri@um.edu.mt
Abstract
INTRODUCTION: A number of factors affect the dimensional stability of a material. These factors include curing conditions, material solubility, leaching, and time. The aim of this study was to evaluate the restrained dimensional change in the vertical direction as a function of the ambient conditions, fluid uptake, solubility, and leaching of white mineral trioxide aggregate (MTA) and Portland cement stored in Hank's balanced salt solution (HBSS) over a period of 28 days. METHODS: The dimensional change in the vertical direction over a 28-day period was determined using a linear variable differential transducer (LVDT) on laterally restrained test samples. The fluid uptake and solubility of both MTA and Portland cement was also evaluated. The leaching in water and HBSS was assessed using inductively coupled plasma. RESULTS: MTA was more soluble than Portland cement. Both materials absorbed water and physiological solution, with Portland cement displaying a lower uptake than MTA. Both cements exhibited a net expansion when in contact with a physiological solution and released high levels of calcium. MTA leached bismuth. Both calcium and bismuth ion release was higher in HBSS than in water. Phosphorus ions in HBSS were depleted when in contact with both MTA and Portland cement. CONCLUSIONS: The MTA was very susceptible to ambient conditions. The addition of bismuth oxide to MTA reduced the leaching of calcium hydroxide, increased the material solubility, and caused deterioration in material dimensional stability. Further research is necessary to establish the material porosity and its effect on the dimensional stability. Copyright Â
INTRODUCTION: A number of factors affect the dimensional stability of a material. These factors include curing conditions, material solubility, leaching, and time. The aim of this study was to evaluate the restrained dimensional change in the vertical direction as a function of the ambient conditions, fluid uptake, solubility, and leaching of white mineral trioxide aggregate (MTA) and Portland cement stored in Hank's balanced salt solution (HBSS) over a period of 28 days. METHODS: The dimensional change in the vertical direction over a 28-day period was determined using a linear variable differential transducer (LVDT) on laterally restrained test samples. The fluid uptake and solubility of both MTA and Portland cement was also evaluated. The leaching in water and HBSS was assessed using inductively coupled plasma. RESULTS: MTA was more soluble than Portland cement. Both materials absorbed water and physiological solution, with Portland cement displaying a lower uptake than MTA. Both cements exhibited a net expansion when in contact with a physiological solution and released high levels of calcium. MTA leached bismuth. Both calcium and bismuth ion release was higher in HBSS than in water. Phosphorus ions in HBSS were depleted when in contact with both MTA and Portland cement. CONCLUSIONS: The MTA was very susceptible to ambient conditions. The addition of bismuth oxide to MTA reduced the leaching of calcium hydroxide, increased the material solubility, and caused deterioration in material dimensional stability. Further research is necessary to establish the material porosity and its effect on the dimensional stability. Copyright Â
Authors: J Camilleri; L Grech; K Galea; D Keir; M Fenech; L Formosa; D Damidot; B Mallia Journal: Clin Oral Investig Date: 2013-10-08 Impact factor: 3.573
Authors: Ya-Juan Guo; Tian-Feng Du; Hong-Bo Li; Ya Shen; Christophe Mobuchon; Ahmed Hieawy; Zhe-Jun Wang; Yan Yang; Jingzhi Ma; Markus Haapasalo Journal: BMC Oral Health Date: 2016-02-20 Impact factor: 2.757
Authors: Roberta Bosso-Martelo; Juliane Maria Guerreiro-Tanomaru; Raqueli Viapiana; Fábio Luis Camargo Vilella Berbert; Maria Inês Basso Bernardi; Mario Tanomaru-Filho Journal: Int Sch Res Notices Date: 2015-02-23