[Invaginated dental elements. I. Occurrence and pathogenesis].

These tooth abnormalities can be classified into four major groups, depending on the depth of the invagination. A typical example from group four is described. Thorough röntgenological examination reveals a frequent occurrence. The great diversity in nomenclature and the variety of morphogenetic and etiological theories show that genetic factors are very important in the development of an invaginated tooth and that knowledge concerning the patho-mechanism is very inadequate.