[Osteoradionecrosis. I. Etiology, pathogenesis, clinical aspects and risk factors].

摘要: In curative therapy of mouth-cavity and oropharyngeal carcinomas the osteoradionecrosis has to be accepted as a calculated risk with an incidence 4-35%. It is question radio-caused bone death that comes about by progressive irreversible morphological alterations at bones vessels: Loss osteocytes, active osteoblasts osteoclasts (hypocellularity), injury normal metabolism, slackening regeneration process, extreme susceptibility infections devitalized bone, radio-induced obliterating endarteritis hyalinization, thrombosis fibrosing vessels, obliteration lumen gradual reduction blood-supply level tissue (hypovascularity hypoxemia: Aseptic osteoradionecrosis, radio-osteonecrosis). If there secondary infection dental, periodontal or traumatic origin additionally, condition explodes septic symptoms findings radio-osteomyelitis. The begins more frequently in mandibula than maxilla. cumulative 30% after 6, 60% 12, 80% 24 months. duration follows exponential curve constant probability necrosis termination any moment event which monthly healing nearly 0.06. Risk factors for formation are tumor neighbourhood teeth, dosis, stage, irradiation technique, status teeth well carrying out tooth extractions. Tumors have fivefold higher risk, 80 Gy irradiated patients 2.9-fold toothed 2.6-fold, altogether high-risk 17.7-fold low-risk patients. Promoting caries, parodontosis, periapical pathology, trauma, irritation artificial elective extraction before irradiation, jaw operations because remains recurrence tumor.