Article

Amelogenin-chitosan matrix promotes assembly of an enamel-like layer with a dense interface.

Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, USA.
Acta biomaterialia (Impact Factor: 5.68). 04/2013; 9(7). DOI: 10.1016/j.actbio.2013.04.004
Source: PubMed

ABSTRACT Biomimetic reconstruction of tooth enamel is a significant topic of study in material science and dentistry as a novel approach for prevention, restoration, and treatment of defective enamel. We developed a new amelogenin-containing chitosan hydrogel for enamel reconstruction that works through amelogenin supramolecular assembly, stabilizing Ca-P clusters and guiding their arrangement into linear chains. These amelogenin Ca-P composite chains further fuse with enamel crystals and eventually evolve into enamel-like co-aligned crystals, anchoring to the natural enamel substrate through a cluster growth process. A dense interface between the newly-grown layer and natural enamel was formed and the enamel-like layer had improved hardness and elastic modulus compared to etched enamel. We anticipate that chitosan hydrogel will provide effective protection against secondary caries because of its pH-responsive and antimicrobial properties. Our studies introduce amelogenin-containing chitosan hydrogel as a promising biomaterial for enamel repair and demonstrate the potential of applying protein-directed assembly to biomimetic reconstruction of complex biomaterials.

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