Re: Implant placement after radiation in pateint with CA

[sushantpatel_doc]

Osteoradionecrosis is a real nasty complication of the radiotherapy in the treatment of head and neck cancer. Clinical manifestations of osteoradionecrosis may include continuous disturbing pain, orofacial fistula, exposed necrotic bone, pathologic jaw fracture, and purulence. It is more commonly seen in the mandible than in the maxilla due to the relatively decreased vascularity and increased bone density of the mandible. The mandible often receives a greater dose of radiation than the maxilla for the latter reason. Radiation dose is a contributing factor to the development of osteoradionecrosis as well as tumor location, dental trauma, the premorbid dentition and neglected oral health, or concomitant chemoradiotherapy if ever done. Sometimes, the question is that what happens when a patient already having implants in his/her mouth, develops a cancer, needing irradiation to the jawbone and what would the effect of these implants on the surrounding bone during radiotherapy of oral, nasal, and paranasal neoplasms be? Radiation scatter can cause both soft and hard tissue complications in the oral cavity making scattered radiation an important factor in head and neck region radiotherapy planning. It has not been even proved that a local overdose on the order of 15% to 21% will cause a significant increase in the incidence of bone necrosis around the osteo-integrated titanium implants, hence, they do not need to be removed before radiotherapy. As the primary osseous complication arising from radiation injury, osteoradionecrosis has clinically been defined in the literature as irradiated bone that has failed to heal in twelve weeks. As a matter of fact, it is a non-healing wound or a slow-healing radiation-induced ischemic necrosis of the bone with associated soft tissue necrosis even without having any sign of tumor cell seeding or metastasis. Dose enhancement factor that may contribute to osteoradionecrosis are always higher than 6000 cGy delivered by 25-MV x-ray machines. To handle these cases, a pre-surgical HBO diving protocol is mandatory, and no doubt that only a specialist oral and maxillofacial surgeon should take care of them. For those cases that the amount of received radiation is equal to 4000 cGy or less, and a time lapse(of twenty years for your patient), then go for it, and don’t be afraid of losing any litigation.