title: Hypodontia: An Update on Its Etiology, Classification, and Clinical Management.
abstract: Hypodontia, or tooth agenesis, is the most prevalent craniofacial malformation in humans. It may occur as part of a recognised genetic syndrome or as a nonsyndromic isolated trait. Excluding third molars, the reported prevalence of hypodontia ranges from 1.6 to 6.9%, depending on the population studied. Most affected individuals lack only one or two teeth, with permanent second premolars and upper lateral incisors the most likely to be missing. Both environmental and genetic factors are involved in the aetiology of hypodontia, with the latter playing a more significant role. Hypodontia individuals often present a significant clinical challenge for orthodontists because, in a number of cases, the treatment time is prolonged and the treatment outcome may be compromised. Hence, the identification of genetic and environmental factors may be particularly useful in the early prediction of this condition and the development of prevention strategies and novel treatments in the future.
authors.affiliation: Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
authors.forename: Azza Husam
authors.initials: AH
authors.lastname: Al-Ani
authors.affiliation: Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
authors.forename: Joseph Safwat
authors.initials: JS
authors.lastname: Antoun
authors.affiliation: Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
authors.forename: William Murray
authors.initials: WM
authors.lastname: Thomson
authors.affiliation: Department of Biochemistry, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
authors.forename: Tony Raymond
authors.identifier: 0000-0003-0844-8726
authors.initials: TR
authors.lastname: Merriman
authors.affiliation: Department of Oral Sciences, Faculty of Dentistry, University of Otago, Dunedin, New Zealand.
authors.forename: Mauro
authors.identifier: 0000-0003-4516-647X
authors.initials: M
authors.lastname: Farella
mesh_terms: D000848:Anodontia / Q000453:epidemiology* / Q000209:etiology / Q000235:genetics / Q000473:pathology*; D001641:Bicuspid / Q000254:growth & development / Q000473:pathology*; D006801:Humans; D007180:Incisor / Q000254:growth & development / Q000473:pathology*; D008334:Mandible / Q000254:growth & development / Q000473:pathology; D008437:Maxilla / Q000254:growth & development / Q000473:pathology