Event Abstract Back to Event Preparation of an MTA through spray-pyrolysis Sumin Lim1, Jeong-Cheol Lee1, Seung-Hoon Um1 and Sanghoon Rhee1 1 Seoul National University, Dental Biomaterials Science, Korea The spray-pyrolysis method coupled with a sol-gel reaction was newly applied to synthesize a homogeneous and small MTA powder because it provides a relatively easy way to control stoichiometry, can achieve high purity, is highly reproducible, and is a good candidate for mass production via a continuous process. After the synthesis of MTA powder, its shape, phase, setting characteristics, and compressive strengths as a function of setting time were evaluated. The MTA powder was synthesized by a spray pyrolysis after sol-gel reaction. A CaO-SiO2-Al2O3 gel solution was prepared by the hydrolysis and condensation reaction of calcium nitrate tetrahydrate (Aldrich), tetraethyl orthosilicate (Aldrich), aluminum nitrate nonahydrate (Aldrich), and nitric acid (Aldrich) at 70oC for 1 h under Ar atmosphere. The CaO-SiO2-Al2O3 gel solution was then made into small droplets using an ultrasonic spray generator fed into an alumina reaction tube at 1300oC with the carrier gas flow rate of 20 L/min made by a compressor. For setting test, the MTA powder was mixed with deionized water on glass slabs and condensed using a plugger into 6 mm in height and 4 mm in diameter custom made split Delron molds. The molds were occluded on one end with a microscope glass slide, wrapped with a damp gauze sponge, and allowed to set for 7 days at 37oC in 95% humidity chamber. Setting time was evaluated using the procedure set out in ISO 9917-1: 2007. The compressive strengths of the samples after different periods of setting time were determined using a general purpose testing machine. All microstructures were observed by a filed emission scanning electron microscope (FE-SEM). The crystal phases of the specimens before and after different periods of setting time were evaluated using an X-ray diffractometry (XRD). XRD pattern was collected of the powder prepared by the spray-pyrolysis at 1300oC; the powder was mainly composed of tricalcium silicate, dicalcium silicate, and tricalcium aluminate with little amount of glass phase. All particles were nearly spherical and had little clusters of smaller spherical particles. The average particle size was 0.8 µm and its particle size distribution ranged from 0.1 μm to 1.0 μm. After setting, interlocked fiber-like calcium-silicate-hydrates and columnar-structured calcium hydroxide were observed to occur. The final setting time was about 15 minutes. The compressive strength after 7 days of setting was about 50 MPa. The fast setting time and high compressive strength must be originated from small particle size, elemental homogeneity in a particle, low crystallinity, and a substantial amount of glass phase, which produced fast dissolution capacity and resultantly fast hydration and reaction with water. These results suggest that newly synthesized MTA demonstrate encouraging potential as a material for pulp capping due to its fast setting capacity, easy handling property, and high compressive strength. This research was supported by the Bio & Medical Technology Development Program of the National Research Foundation (NRF) funded by the Ministry of Science, ICT & Future Planning (NRF-2005-2000113). Keywords: Crystal growth, biomedical application, Bone graft, Nano/micro particle Conference: 10th World Biomaterials Congress, Montréal, Canada, 17 May - 22 May, 2016. Presentation Type: Poster Topic: Combinatorial approaches to biomaterial design Citation: Lim S, Lee J, Um S and Rhee S (2016). Preparation of an MTA through spray-pyrolysis. Front. Bioeng. Biotechnol. Conference Abstract: 10th World Biomaterials Congress. doi: 10.3389/conf.FBIOE.2016.01.02476 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Mar 2016; Published Online: 30 Mar 2016. Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Sumin Lim Jeong-Cheol Lee Seung-Hoon Um Sanghoon Rhee Google Sumin Lim Jeong-Cheol Lee Seung-Hoon Um Sanghoon Rhee Google Scholar Sumin Lim Jeong-Cheol Lee Seung-Hoon Um Sanghoon Rhee PubMed Sumin Lim Jeong-Cheol Lee Seung-Hoon Um Sanghoon Rhee Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.