title: [Phenotype analysis and the molecular mechanism of enamel hypoplasia].
abstract: Enamel hypoplasia is a surface defect of the tooth crown caused by a disturbance of enamel matrix secretion. Enamel hypoplasia may be inherited, or result from illness, malnutrition, trauma, or high concentrations of fluorides or strontium in the drinking water or food. Different types of enamel hypoplasia have been distinguished, such as pit-type, plane-type, and linear enamel hypoplasia. Hypoplasia has been related to the intensity and duration of stress events, the number of affected ameloblasts, and their position along the forming tooth crown. Amelogenesis imperfecta (AI) is a heterogeneous group of inherited defects in dental enamel formation, most teeth are affected in both the primary and permanent dentition. The malformed enamel can be unusually thin, soft, rough and stained. The strict definition of AI includes only those cases where enamel defects occur in the absence of other symptoms. Currently, there are seven candidate genes for AI: amelogenin, enamelin, ameloblastin, tuftelin, distal-less homeobox 3, enamelysin, and kallikrein 4. Since the enamel is formed according to a strict chronological sequence, and once formed, undergoes no repair or regeneration. Then the analysis the phenotype of enamel hypoplasia can provide insights of the severity of inherited or environmental stress and the molecular mechanism during the period of enamel formation.
authors.affiliation: Department of Endodontic and Operative Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Lv
authors.forename: Xue-jun
authors.initials: XJ
authors.lastname: Gao
mesh_terms: D000567:Amelogenesis Imperfecta / Q000209:etiology / Q000235:genetics*; D053523:Amelogenin / Q000235:genetics*; D003743:Dental Enamel / Q000254:growth & development / Q000503:physiopathology; D003744:Dental Enamel Hypoplasia / Q000209:etiology / Q000235:genetics*; D003746:Dental Enamel Proteins / Q000235:genetics*; D006801:Humans; D053519:Matrix Metalloproteinase 20 / Q000235:genetics; D009154:Mutation; D010641:Phenotype
chemical_list: D053523:Amelogenin; D003746:Dental Enamel Proteins; C038456:tuftelin; C507111:MMP20 protein, human; D053519:Matrix Metalloproteinase 20