https://www.has-sante.fr/jcms/p_3301902/fr/agenesies-dentaires-multiples-oligodontie-et-anodontie 2021 France practice guideline partial congenital absence of teeth anodontia dental diseases anodontia, nos Oligodontia Anodontia disease of teeth, nos chronic disease Agenesis chronic disease, nos Handbook Diseases Chronic disease congenital absence, nos