tooth agenesis, selective, type 1

(redirected from second premolars and third molars, absence of)

tooth agenesis, selective, type 1

A condition (OMIM:106600) characterised by non-syndromic agenesis of one or more teeth, which is divided into hypodontia (agenesis of less than 6 permanent teeth) and oligodontia (agenesis of 6 or more permanent teeth).

Molecular pathology
Caused by defects of MSX1, which encodes a homeobox protein involved in epithelial-mesenchymal signalling that has roles in craniofacial development.