DIFFERENTIAL DENSITOMETRIC PROFILE IN THE MANDIBLE OF PATIENTS SUFFERING FROM RARE DISEASES. DESCRIPTION OF CASES

Abstract

Maxillary bone owns a high metabolic turnover, hence morbid changes can be promptly expressed. By means of a special densitometric device, the bone mineral pattern of healthy subjects has been described, and assessments have been made of patients with abnormalities. With the pQCT system the boundaries of segments with different bone mineral density values are known, the thresholds being 110, 310, 430 and 900 mg/cm3, respectively, allowing the separation of calcified tissues into type IV quality (osteopenia) to type I (dense), and intermediate types. For example the percentage of type IV at the mandible of a healthy male is within the range of 11-28%, and within 8-14% for women. In a male with aromatase deficiency types I to III are reduced. In a case of osteopenia secondary to hyperparathyroidism, types I to III are decreased; and in an osteopenia due to hypothyroidism, type IV area is enlarged, up to 35% of jaw section. In a child with osteogenesis imperfecta type IV is within normal limits, but all other values are reduced. In an acromegalic patient, type I is in the lower range. In a patient with Paget's disease, type IV is reduced while the rest are enlarged. In a case of Marfan syndrome both types I and II are enlarged. Consequently, the incidental finding of jaw deformations or abnormal densitometric quantifications, in patients lacking a proper diagnosis, should lead practical dentists to refer patients for their clinical evaluation and management.