A SCOPING REVIEW: GENE MUTATIONS OF NONSYNDROMIC HYPODONTIA AND ITS PREVALENCE IN GENDER AND TYPE OF TEETH

Abstract

Non-syndromic hypodontia is a developmental anomaly characterized by the absence of one to six of permanent teeth. The goal of this review was to identify all known gene mutations, prevalence of gender and type of teeth, to review current research and identify knowledge gaps on the topic of nonsyndromic hypodontia. Three electronic databases were performed (Science Direct, PubMed, and Scopus) and restricted to English papers published after 2012 until 2019. Search terms were combined as follows: Hypodontia or 'non-syndromic hypodontia' and 'genes' or 'tooth anomaly' and 'mutation' or 'genes' and were checked against the inclusion criteria independently by two investigators. From 16 studies, five genes currently known caused non-syndromic hypodontia: WNT10A (37 variants, 256 patients), MSX1 (9 variants, 112 patients), PAX9 (17 variants, 79 patients), AXIN2 (8 variants, 60 patients) and EDA (2 variants, 11 patients). It was demonstrated that females exhibited a higher prevalence of hypodontia with 89.3% as compared to males with 84.2%. The most commonly missing teeth was a lateral incisor, followed by second premolar and central incisor. Five genes, including WNT10A, PAX9, MSX1, AXIN2 and EDA, are currently considered to have the ability to cause nonsyndromic hypodontia. Lateral incisor was found to be commonly missing teeth and there was an increased risk for females to have hypodontia than males.