下顎頭および下顎角部に骨変化をきたした進行性全身性硬化症の１例

Abstract

We report on patient with progressive systemic sclerosis (PSS) who had osseous resorptive changes of the mandibular condyles and angles with induration and atrophy of the adjacent soft tissue. The patient was a 51-year-old woman who had a history of PSS with pulmonary fibrosis for approximately 18 years and had been treated with corticosteroid and oxygen therapy. In addition, tightness of the facial skin, mimic muscles, and masticatory muscles with a mask-like face, classic features of PSS, were seen. There was also limited opening mouth due to microstoma and pain of the temporomandibular joint, with the interincisal distance being 22mm. A panoramic radiograph showed erosion of the condyles and significant resorption of the bilateral mandibular angle and ramus in the region of the insertion of the masseter and medial pterygoid muscles. CT images also revealed marked erosion of the mandibular angles, without destruction of the cortical bone. Anterior displacement of the bilateral disk, rupture of the right disk, and decreased marrow signal intensity of the right condyle on T 1-weighted MR images of the temporomandibular joint were also present. These osseous resorptive changes were suggested to be caused by local pressure from the overlying sclerotic facial skin and the atrophic masseter and medial pterygoid muscles.