Magnesium phosphate cements for endodontic applications with improved long‐term sealing ability. (3rd May 2013)

• Record Type: Journal Article
• Authors: Mestres, G.; Aguilera, F. S.; Manzanares, N.; Sauro, S.; Osorio, R.; Toledano, M.; Ginebra, M. P.
• Is Part Of: International endontic journal. Volume 47:Number 2(2014:Feb.)
• Page Start: 127
• Page End: 139
• Publication Date: 2013-05-03
• Subjects: Endodontics -- Periodicals; 617.6342
• DOI: 10.1111/iej.12123
• Languages: English
• ISSNs: 0143-2885

Abstract

<abstract abstract-type="main" xml:lang="en" id="iej12123-abs-0001"> <title>Abstract</title> <sec id="iej12123-sec-0001" sec-type="section"> <title>Aim</title> <p>To characterize three radiopaque Magnesium Phosphate Cements (MPCs) developed for endodontic purposes.</p> </sec> <sec id="iej12123-sec-0002" sec-type="section"> <title>Methodology</title> <p>Three experimental MPCs containing Bi<sub>2</sub>O<sub>3</sub> were formulated. The experimental cements, which consisted of mixtures of magnesium oxide with different phosphate salts, were characterized for setting time, injectability, porosity, compressive strength and phase composition. The long‐term sealing ability of the experimental MPCs applied in single‐rooted teeth as root canal filling material or as sealer in combination with gutta‐percha was also assessed using a highly sensitive fluid filtration system. A mineral trioxide aggregate (MTA) cement was used as control. Statistical analysis was performed with two‐ or three‐way analysis of variance (<sc>anova</sc>) and Tukey's test was used for comparisons.</p> </sec> <sec id="iej12123-sec-0003" sec-type="section"> <title>Results</title> <p>The addition of 10 wt% Bi<sub>2</sub>O<sub>3</sub> within the composition of the MPCs provided an adequate radiopacity for endodontic applications according to ISO 6876 standard. The reaction products resulting from the MPCs were either struvite (MgNH<sub>4</sub>PO<sub>4</sub>·6H<sub>2</sub>O) or an amorphous sodium magnesium phosphate. The porosity of the three MPCs ranged between 4% and 11%. The initial setting time of the experimental cements was between 6 and 9 min, attaining high early compressive strength values (17‐34 MPa within 2 h). All MPC formulations achieved greater sealing ability than MTA (<italic>P </italic><<italic> </italic>0.05) after 3 months, which was maintained after 6 months for two of the experimental cements (<italic>P</italic> < 0.05).</p> </sec> <sec id="iej12123-sec-0004" sec-type="section"> <title>Conclusions</title> <p>These MPCs had adequate handling and mechanical properties and low degradation rates. Furthermore, a stable sealing ability was demonstrated up to 6 months when using the cement both as root filling material and as sealer in conjunction with gutta‐percha.</p> </sec> </abstract>