RESUMO
The paper presents a family with hereditary transmitted Marie-Sainton dysplasia affecting the father and his both children. This is a rare syndrome presenting an autosomal pattern of inheritance, characterized by a generalized defect in both membranous and endochondral bone formation resulting in clavicular aplasia, delayed ossification of the fontanelles and the sutures of the skull and prolonged retention of deciduous dentition with delayed eruption of the permanent teeth. The diagnosis is suggested by more or less complete clinical picture and confirmed by multiple radiological explorations (skull, thorax, spinal column, pelvis) and genetical examination. The genetic mutation for cleidocranial dysplasia (CCD) is found on chromosome six and is called CBFA1 (short for core biding factor al or RUNX2) and is the only gene known to be associated with CCD. The normal version of CBFA1 acts to induce osteoblasts which are the type of cells that lay down bone. Although associated psychosocial disorders can occur, the prognosis and life expectancy of this condition are favorable being conditioned however by the complexity of orthodontic procedures which are determinant for these patients life quality.
