Calcifying acne lesions.

Cutaneous calcium deposition can occur in long-term inflammation. The deposition of calcium in long-standing acne may produce either small pigmented nodules or no visible lesions. The former type is or no visible lesions. The former type is much less common, with the nodules containing particulate spheres of mineral which probably represent true osteomas. Both types of calcification can be demonstrated roentgenographically and may occur in as many as half of all cases of severe long-standing acne.