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Tooth agenesis is one of the most common dental genetic disorders. Single or combination of multiple genetic factors is believed to be involved in the molecular pathogenesis in addition to the various harmful environmental factors (Thesleff, 2003). Hypodontia or oligodontia can occur as an isolated form or syndromic phenotype (Song et al., 2020; Yang et al., 2020). Because the tooth organ is ectodermally derived, the most frequent manifestation of tooth agenesis is as a syndromic phenotype of ectodermal dysplasia (ED). ED is a collection of genetic disorders affecting more than two tissues with ectodermal origin (Wright et al., 2019), and the current search in the Online Mendelian Inheritance in Man database resulted in 233 EDs of which 65 EDs have tooth agenesis.