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Repairing human tooth enamel with leucine-rich amelogenin peptide–chitosan hydrogel

  • Kaushik Mukherjee (a1), Qichao Ruan (a1), David Liberman (a1), Shane N. White (a2) and Janet Moradian-Oldak (a3)...

We have recently reported the repair of carious enamel using a full-length amelogenin–chitosan hydrogel through guided stabilization and growth of mineral clusters. The objective of this study was to further evaluate the enamel repair potential of smaller amelogenin peptides like LRAP (leucine-rich amelogenin peptide) and compare their efficiency with their full-length counterpart. The demineralized tooth slices treated with a single application of LRAP–chitosan hydrogel for 3 days showed a dense mineralized layer consisting of highly organized enamel-like apatite crystals. Focus-ion beam technique showed a seamless growth at the interface between the repaired layer and native enamel. There was a marked improvement in the surface hardness after treatment of the demineralized sample with almost 87% recovery of the hardness value to that of sound enamel sections. This current approach can inspire the design of smaller peptide analogues based on naturally occurring amelogenin as a competent, low-cost, and safe strategy for enamel biomimetics to curb the high prevalence of incipient dental caries.

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