Innovative dental mineral trioxide aggregate composition based on a nanostructured calcium phosphate biomimetic filler

Abstract

Mineral trioxide aggregate (MTA)-based dental materials are widely used in endodontic therapy due to their favorable sealing ability, biocompatibility, and bioactivity; however, ongoing research seeks to enhance their functional performance and biological responses by incorporating advanced biomimetic and nanostructured fillers. This study reports the development and comprehensive characterization of a novel MTA-type dental material based on a nanostructured calcium phosphate biomimetic filler. The base MTA was obtained from synthesized dental cement and commercial bismuth oxide, which served as the radiopacifier. To obtain the biomimetic obturating composition (BOC), base MTA was mixed with biomimetic filler consisting of nanostructured calcium-deficient, silicon- and fluorine-substituted hydroxyapatite synthesized using the authors’ methodology. Structural-morphological and physicochemical characteristics of all components were investigated using X-ray diffraction, Fourier-transform infrared spectroscopy, and scanning and transmission electron microscopy. In accordance with International Organization for Standardization (ISO) 6876:1986 requirements, key functional properties of BOC samples, such as flowability (20–23 mm), working time (630–660 s), setting time (420–680 s), radiopacity (>3 mmAl), and solubility (1.6–2.1%) were studied. In vitro bioactivity of BOC samples was evaluated through calcium ion release in simulated body fluid (SBF) and acetate buffer, as well as apatite-forming ability in SBF. It was found that incorporating the nanostructured biomimetic filler significantly enhanced calcium ion release and promoted the formation of a surface apatite layer, the thickness of which increased with filler content. The results demonstrate that the proposed BOC exhibits improved bioactivity while maintaining acceptable physicochemical and functional characteristics, indicating its potential for dental application.

Keywords

Dental materials / Mineral trioxide aggregate / Biomimetic hydroxyapatite / Calcium phosphate / Sol-gel synthesis / Bioresorbability

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