Developmental biology and genetics of dental malformations.

[dentin dysplasia]

The synthesis of tooth development biology with human studies focusing on inherited conditions that specifically interfere with tooth development is improving our understanding of normal and pathological tooth formation . The type of inherited dental malformations observed in a given kindred relate to when , during odontogenesis , the defective gene is critically expressed . Information about the protein encoded by the defective gene and the resulting dental phenotype helps us understand the major processes underway at different stages during tooth development . Genes affecting early tooth development (PAX 9 , MSX 1 , and AXIN 2 ) are associated with familial tooth agenesis or oligodontia . Genes expressed by odontoblasts (COL 1 A 1 , COL 1 A 2 , and DSPP ), and ameloblasts (AMELX , ENAM , MMP 20 , and KLK 4 ) during the crown formation stage , are associated with dentinogenesis imperfecta , dentin dysplasia , and amelogenesis imperfecta . Late genes expressed during root formation (ALPL and DLX 3 ) are associated with cementum agenesis (hypophosphatasia ) and taurodontism . Understanding the relationships between normal tooth development and the dental pathologies associated with inherited diseases improves our ability to diagnose and treat patients suffering the manifestations of inherited dental disorders .

Diseases
Validation

Diseases presenting "taurodontism" symptom

dentin dysplasia

dentinogenesis imperfecta

oligodontia

This symptom has already been validated