Our centre is labeled by the French Ministry of Health as a national reference centre for orodental manifestations of rare diseases. Orodental anomalies are one of the phenotypical aspects of at least 900 rare diseases or syndromes. They are often described in association with other organs or system malformations, which is understandable, because the same genes and signaling 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, by signaling pathways and by syndrome families. These anomalies become increasingly identified as diagnostic and predictive traits and require specific management.

The reference centre welcomes 2 groups of patients:

• Patients from childhood to adulthood presenting rare developmental1 either isolated or syndromic, orodental anomalies with spetiflt track for hypodontia/oligodontia patients, dentinogenesis or amelogenesis imperfect patients. These patients require long term complex multidisciplinary treatments.

• Rare disease patients with specific orodental multidisciplinary management needs (prevention, sedation, genera anesthesia ..) because of their deficiency (neurologic, sensoriaj, age related ... ) but in relation with non-specific oral diseases such as caries, periodontal diseases, trauma...Our expertise mission, defined by Rare Disease National Plan, is to act as a tertiary centre from diagnosis to treatment (referral centre) for other health professionals.Our center takes care of 800 patients per year.

The outpatient service has 3 individual dedicated treatment dental practices with fully equipped dental chairs and large rooms for ambulatory care, 1 dedicated waiting room, X-Ray facilities including cone beam computed tomography (CBCT), 1 recovery room after conscious sedation, conscious inhalation sedation equipments, 1 microscope for endodontic treatment, surgical operating theaters for implant surgery, 1 general anesthesia session per week in the Strasbourg children hospital (Hautepierre) with specific mobile dental equipments, 1 office for the management and database development and maintenance, 1 practice and chair for research programs.

The various expertises (emergency service, pediatric dentistry, preventive dentistry, conservative dentistry, endodontics, prosthetics, periodontology, surgery, orthodontics, oral biology) are gathered within the reference centre. The centre collaborates with other reference/competence centres and hospital units (genetics, pediatrics, dermatology, maxillofacial). Our centre set up a child-> adult transition for the follow-up of former pediatric patients. Our centre developed the genetic diagnosis of these conditions.

For training activities the centre provides regional, national, international expert training (university, continuing medical /dental information, patients) and has set-up national/international guidelines.