Orodental Manifestations of Rare Diseases

OroDental anomalies are one of the phenotypical aspects of at least 900 rare diseases or syndromes affecting by definition less than 1 in 2000 individual within the population (almost 25 million persons in Europe). They are often described in association with other organs or system malformations, which is understandable, because the same genes and signalling pathways regulate the oral cavity formation or odontogenesis and the development of other organs. The various dental and orofacial anomalies can be classified by type (anomalies of tooth number, shape, size, structures of mineralized tissues, eruption, resorption, tumors; anomalies of oral mucosa; anomalies of tongue…), by signalling pathways and by syndrome families. These anomalies (for example hypodontia/oligodontia, amelogenesis imperfecta, dentinogenesis imperfecta…) become increasingly identified as diagnostic and predictive traits. Not only is it important to recognise, name appropriately and integrate these dysmorphic clues into the patient dysmorphology analysis but it is essential to synthesize the observations and confront them to existing data about similar orodental anomalies encountered in some of the corresponding mutant mouse models. Translational approaches in development and medicine, are relevant to gain understanding of molecular events underlying clinical manifestations and to enhance diagnostic accuracy. The aim of this study is to improve the knowledge, diagnosis and care of oral cavity pathologies encountered in rare diseases via the identification and gathering of national and international patient cohorts and to structure the molecular diagnosis behind these conditions via targeted next-generation sequencing assays. Data collection is implemented on validated accredited tools (databases) complying with the legal regulations about patient data protection and medical record collection. All information is anonymized. New effective diagnosis and therapeutic tools are being developed.