title: A simplified genetic design for mammalian enamel.
abstract: A biomimetic replacement for tooth enamel is urgently needed because dental caries is the most prevalent infectious disease to affect man. Here, design specifications for an enamel replacement material inspired by Nature are deployed for testing in an animal model. Using genetic engineering we created a simplified enamel protein matrix precursor where only one, rather than dozens of amelogenin isoforms, contributed to enamel formation. Enamel function and architecture were unaltered, but the balance between the competing materials properties of hardness and toughness was modulated. While the other amelogenin isoforms make a modest contribution to optimal biomechanical design, the enamel made with only one amelogenin isoform served as a functional substitute. Where enamel has been lost to caries or trauma a suitable biomimetic replacement material could be fabricated using only one amelogenin isoform, thereby simplifying the protein matrix parameters by one order of magnitude.
authors.affiliation: Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA. mlsnead@usc.edu
authors.forename: Malcolm L
authors.initials: ML
authors.lastname: Snead
authors.forename: Dan-Hong
authors.initials: DH
authors.lastname: Zhu
authors.forename: Yaping
authors.initials: Y
authors.lastname: Lei
authors.forename: Wen
authors.initials: W
authors.lastname: Luo
authors.forename: Pablo O
authors.initials: PO
authors.lastname: Bringas
authors.forename: Henry M
authors.initials: HM
authors.lastname: Sucov
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Rauth
authors.forename: Michael L
authors.initials: ML
authors.lastname: Paine
authors.forename: Shane N
authors.initials: SN
authors.lastname: White
mesh_terms: D053523:Amelogenin / Q000235:genetics / Q000378:metabolism; D000818:Animals; D003743:Dental Enamel / Q000378:metabolism* / Q000648:ultrastructure; D005786:Gene Expression Regulation; D055879:Gene Knock-In Techniques; D005818:Genetic Engineering / Q000379:methods*; D008322:Mammals / Q000235:genetics*; D008422:Materials Testing; D051379:Mice; D020161:Physical Chromosome Mapping; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism
chemical_list: D053523:Amelogenin; D012333:RNA, Messenger