Chronic ulceration at this site can cause linear fibrous hyperplasia (irritation fibroma). Chondromyxoid fibroma is a type of cartilaginous tumor. The central odontogenic fibroma is a rare benign odontogenic tumor. This condition should be differentiated from Nonossifying fibroma and fibrous dysplasia of bone. The cystic fibroma (fibroma cysticum) has central softening or dilated lymphatic vessels. Some cases have been described, in which an osteosarcoma has arisen from a desmoplastic fibroma. The presence of an ovarian fibroma can cause ovarian torsion in some cases. Immunologically, the papillomatosis virus is not related to fibroma or myxoma in rabbits. The photo shows a soft fibroma of the eyelid. The myxofibroma (fibroma myxomatodes) is produced by liquefaction of the underlying soft tissue. Proliferation of tissues is similar to an Ameloblastic Fibroma. Not to be confused with ossifying fibroma. PCNA and Ki67 immunoreactivity happens in case of fibroma and peripheral granuloma. Radiographically, ameloblastic fibroma has a variable appearance.