Anodontia or hypodontia

Anodontia is a rare genetic disorder characterized by the congenital absence of all primary or permanent teeth. It is divided into two subsections, complete absence of teeth or only some absence of teeth. [Source: Wikipedia ]

May Be Caused by
Aarskog syndrome
Acrofacial dysostosis
ADULT syndrome
Alagille syndrome
Angel-shaped phalangoepiphyseal dysplasia
Bardet-Biedl syndrome
Bloom syndrome
Böök syndrome
Branchio-oto-renal syndrome
Carpenter syndrome
Charlie M syndrome
Cleft lip sequence
Cleidocranial dysostosis
Coffin-Lowry syndrome
Cranioectodermal dysplasia
Crouzon syndrome
Ectodermal dysplasia
EEC syndrome
Ehlers-Danlos syndrome
Ellis-van Creveld syndrome
Epidermal nevus syndrome
Frontometaphyseal dysplasia
GAPO syndrome
Glossopalatine ankylosis syndrome
Goltz syndrome
Grebe-like chondrodysplasia
Hallermann-Streiff syndrome
Hanhart syndrome
HATS syndrome
Hay-Wells syndrome
Incontinentia pigmenti
Johanson-Blizzard syndrome
Kabuki syndrome
KBG syndrome
Kirghizian dermato-osteolysis
Lacrimo-auriculo-dento-digital syndrome
Lenz microphthalmia syndrome
Limb-mammary syndrome
Möbius syndrome
Mulvihill-Smith syndrome
Oculo-dento-osseous dysplasia
Odonto-onycho-dermal dysplasia
Odontotrichomelic syndrome
Oro-palatal dysplasia Bettex-Graf type
Orofaciodigital syndrome type 1
Orofaciodigital syndrome type 2
Osteogenesis imperfecta
Otopalatodigital syndrome type 1
Polycystic ovary syndrome
Rapp-Hodgkin syndrome
Rieger syndrome
Rothmund-Thomson syndrome
Schopf-Schulz-Passarge syndrome
Seckel syndrome
Sjögren-Larsson syndrome
Stoll-Charrow-Poznanski syndrome
Tricho-dento-osseous syndrome
Trichoodontoonychial dysplasia
Trisomy 21
Tuomaala syndrome
Ulnar-mammary syndrome
Van der Woude syndrome
Waardenburg syndrome
Weill-Marchesani syndrome
Williams syndrome
Witkop tooth-nail syndrome
XXXXY syndrome