An Overview of Syndromic Hypodontia

Hypodontia is collectively used to describe the developmental absence of primary or secondary teeth. A number of causes like alterations in the dental lamina development, lack of maturation of tooth germ at the appropriate time, space constraints, systemic and genetic factors may result in missing teeth. With the exception of the third molars, hypodontia is most frequently encountered in lower second bicuspids and upper lateral incisors. Hypodontia is most commonly categorized into two categories: syndromic and non-syndromic hypodontia. Syndromic hypodontia constitutes cases where agenesis of one or more teeth occurs as a result of underlying diagnosable syndromic conditions like ectodermal dysplasia. The more extreme phenotypes of hypodontia include oligodontia with the agenesis of canines, first molars, and second molars and anodontia, and are generally seen in syndromic hypodontia, accompanying and underlying developmental disease. over 200 cleft lip and palate syndromes present with differing extent of hypodontia as a component of their clinical phenotype. The number of missing teeth increases with the extent of cleft. Ectodermal dysplasia consists of a varied group of syndromic presentations resulting from mutations influencing a range of vital congenital pathways such as connection between the overlaying ectoderm and the underlying mesoderm during embryonic growth. Many of these cases present with dental dysplasia and agenesis. In general, dental agenesis may be caused by the arrest of tooth development in the initial bud or cap phase. Care guidelines for such individuals include tooth replacement therapy through fixed and removable prostheses with optional implant support in skeletally mature individuals.