Hypodontia and Anodontia in Children: Etiology, Genetic Factors, Clinical Features, Diagnosis, and Management

Abstract

Tooth agenesis (hypodontia), when a limited number of teeth are missing, is among the more common developmental anomalies of the human dentition. It can present as an isolated, nonsyndromic condition or within a recognized genetic syndrome. When excluding third molars, the prevalence of hypodontia is found to generally range from ~1.6% to 6.9%, with a high variation according to the ethnic and demographic characteristics of the cohort examined. The majority of affected patients show agenesis of one or two teeth, with the maxillary lateral incisors and the mandibular premolars most commonly affected. Tooth agenesis is a multifactorial trait reflecting interaction between genetic predisposition and environmental factors, but it seems that genetic determinants have a predominant role. This condition has important clinical implications, especially in orthodontic management. Hypodontia, a relatively common developmental condition, may necessitate prolonged treatment and abnormal tooth absence/development can complicate space management and occlusal relationships in achieving stable aesthetic and functional outcomes. Better appreciation of the multiple genetic and environmental contributors to tooth agenesis may thus lead to better identification of people at risk earlier in life, which in turn could inform preventative and therapeutic strategies. Anodontia is the most severe type of tooth agenesis and consists of total lack of teeth. Anodontia, unlike tooth loss after eruption, is a congenital developmental disorder in which the individual fails to form teeth during odontogenesis. And one of them is that rare condition that may affect the primary or permanent dentition. Complete tooth agenesis is often found in syndromic forms, especially forms of ectodermal dysplasia wherein other structures derived from the ectoderm become abnormal as well, such as hair (hypotrichosis), nails (onychodystrophy), skin (ichthyosis) and sweat glands.

Keywords:

Hypodontia, Anodontia, Oligodontia, Tooth Agenesis

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