Osteoradionecrosis (ORN) is an aseptic necrosis which occurs due to the post-irradiation decrease in vascularization and cellularity of the bone tissue, in patients who had undergone radiotherapy for tumors in the head-neck area, without persistence of neoplasia.
The physiopathology of ORN is determined by the concurrent presence of hypovascularization, hypocellularity and tissue hypoxia, which compromise the vitality of the bone tissue.
The mandible presents a higher risk compared to the jaw bone, owing to its lower vascularization; the risk increases in edentulous patients and in subjects who faced dental extraction during and after radiotherapy.
The surgical therapy includes radical sequestrectomy or radical hemimandibulectomy and, if possible, a reconstruction with bone grafts; there is some evidence that the hyperbaric oxygen treatment is more beneficial than the conventional antibiotic prophylaxis: HBO stimulates neoangiogenesis, optimizes the tissue perfusion through the oxygen and stimulates the formation of collagen.
HBO should be used before and after Radiotherapy, even though it should always considered that its use is limited to patients who does not have active tumor cells.
The aim of the present study is to clinically assess the regenerative capacity of the epithelial and connective tissues, in response to the pathogenic noxa; in addition, the Authors verified the importance of the surgical-pharmacological treatment, without HBO therapy, as an effective technique in eliminating the bone sequestration or the teeth damaged by Radiotherapy, as the epithelium regeneration can take place only on healthy and vital tissues.
KEY WORDS
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Osteoradionecrosis
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Radiotherapy
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Neoplasia
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Hyperbaric oxygen treatment
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Sequestrectomy
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Epithelium regeneration