title: Surface integrity governs the proteome of hypomineralized enamel.
abstract: Growing interest in the treatment and prevention of Molar/Incisor Hypomineralization (MIH) warrants investigation into the protein composition of hypomineralized enamel. Hypothesizing abnormality akin to amelogenesis imperfecta, we profiled proteins in hypomineralized enamel from human permanent first molars using a biochemical approach. Hypomineralized enamel was found to have from 3- to 15-fold higher protein content than normal, but a near-normal level of residual amelogenins. This distinguished MIH from hypomaturation defects with high residual amelogenins (amelogenesis imperfecta, fluorosis) and so typified it as a hypocalcification defect. Second, hypomineralized enamel was found to have accumulated various proteins from oral fluid and blood, with differential incorporation depending on integrity of the enamel surface. Pathogenically, these results point to a pre-eruptive disturbance of mineralization involving albumin and, in cases with post-eruptive breakdown, subsequent protein adsorption on the exposed hydroxyapatite matrix. These insights into the pathogenesis and properties of hypomineralized enamel hold significance for prevention and treatment of MIH.
authors.affiliation: Department of Pharmacology, The University of Melbourne, Medical Building, Corner of Grattan Street and Royal Parade, Parkville 3010, Victoria, Australia.
authors.forename: J E
authors.initials: JE
authors.lastname: Mangum
authors.forename: F A
authors.initials: FA
authors.lastname: Crombie
authors.forename: N
authors.initials: N
authors.lastname: Kilpatrick
authors.forename: D J
authors.initials: DJ
authors.lastname: Manton
authors.forename: M J
authors.initials: MJ
authors.lastname: Hubbard
mesh_terms: D000327:Adsorption; D053523:Amelogenin / Q000032:analysis; D000818:Animals; D001798:Blood Proteins / Q000032:analysis; D002648:Child; D003176:Complement C3 / Q000032:analysis; D003743:Dental Enamel / Q000737:chemistry / Q000473:pathology; D003744:Dental Enamel Hypoplasia / Q000378:metabolism / Q000473:pathology*; D003746:Dental Enamel Proteins / Q000032:analysis*; D017886:Durapatite / Q000032:analysis / Q000378:metabolism; D006454:Hemoglobins / Q000032:analysis / Q000493:pharmacokinetics; D006801:Humans; D008963:Molar / Q000737:chemistry / Q000473:pathology; D010446:Peptide Fragments / Q000032:analysis; D020543:Proteome / Q000032:analysis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012471:Salivary Proteins and Peptides / Q000032:analysis; D012709:Serum Albumin / Q000032:analysis / Q000493:pharmacokinetics; D014074:Tooth Calcification
chemical_list: D053523:Amelogenin; D001798:Blood Proteins; D003176:Complement C3; D003746:Dental Enamel Proteins; D006454:Hemoglobins; D010446:Peptide Fragments; D020543:Proteome; D012471:Salivary Proteins and Peptides; D012709:Serum Albumin; D017886:Durapatite