[Langerhans cell histiocytosis].

The authors describe a case of a 4 years old boy. In connection with this case they discuss the latest classification of histiocytosis accepted by the Histiocytosis Society, and the stomatological aspects of the disease (severe gingivitis, necrosis of the gingivae, ulceration, and high degree of tooth mobility). The new classes of the disease: Langerhans cell's histiocytosis, Non-Langerhans cell's histiocytosis, malignant histiocytosis.