The author discusses in his paper the problem of genetically conditioned diseases and their manifestation in the craniofacial region. In the introductory part attention is focused on different groups of hereditary diseases, syndromes and their mutual relationships. In the original part of the paper the author presents patients from the group of ectodermal dysplasias and patients with Williams syndrome, incl. genetic, clinical, morphological and stomatiological examination. The author outlines also therapeutic dental procedures for common and specia- lized dental practice.

        Key words: hereditary disease – genetic syndromes – orofacial region – ectodermal dysplasia – genealogical examination – Williams syndrome