Osteoradionecrosis of the mandible: Pathogenesis

Resection and immediate microvascular reconstruction in the management of osteoradionecrosis of the mandible

“…There may be an inability of oxygen to diffuse well in the radiated tissues, which may be a key factor in poor healing response to injury. Bras 4 has shown radiation-induced obliteration of the inferior alveolar artery to be the dominant factor in the development of ORN. The revascularization by collateral vessels is prevented by radiation-induced intimal fibrosis of periosteal vessels and by direct radiation-induced damage to the periosteum.…”

A modified protocol for early treatment of osteomyelitis and osteoradionecrosis of the mandible

“…The histopathologic findings suggested that the radiation-induced obliteration of the inferior alveolar artery is the dominant factor in the onset of ORN leading to an ischemic necrosis of bone. 4 Marx et al 5 also showed that microorganisms are not a primary causative factor but play a role only as contaminants in mandibular ORN. 5 Chronic osteomyelitis (COM) continues to be a serious clinical problem even in this antibiotic era; it has been observed to develop in 5% to 25% of patients after acute hematogenous osteomyelitis.…”

“…Bras et al 4 reported a study in which resection and sequestrectomy samples of patients with ORN of the mandible were compared with samples from irradiated nonosteoradionecrotic mandibles and nonirradiated mandibles. The histopathologic findings suggested that the radiation-induced obliteration of the inferior alveolar artery is the dominant factor in the onset of ORN leading to an ischemic necrosis of bone.…”

Osteoradionecrosis after Radiation Therapy for Head and Neck Cancer: Differentiation from Recurrent Disease with CT and PET/CT Imaging

“…The mandible is the most common site of ORN due to its tenuous blood supply, [1][2][3] though ORN can be seen in almost any bone within a radiated field. The primary factor implicated in the pathogenesis of ORN is the amount of radiation given to the affected bone, with both early (Ͻ2 years from radiation) and late onset ORN (Ͼ2 years from radiation) seen.…”