This is the first article in a two-part series dealing with the effects and manifestations in the oral cavity of radiation therapy of head and neck tumors. In this section, oral mucous membranes, taste buds, edema and trismus, diet, salivary glands, bone, periodontium, teeth, and composition of oral flora are discussed. Dental management of the dentulous patient is then approached; criteria for preradiation extraction are delineated. In the next issue of Head & Neck Surgery, the final article in this series will discuss preradiation and postradiation extractions and will elaborate on the dental management (fluoride treatments, follow-up, and restorative care) of the dentulous patient. Dental management of the edentulous patient will also be presented.

Bacteria↗

PubMedDate not supplied

Radiation therapy of the oral cavity: sequelae and management, part 2.

This is the concluding portion of a two-part series dealing with the effects and manifestations in the oral cavity of radiation therapy of head and neck tumors. Preradiation and postradiation extractions in dentulous patients, as well as dental maintenance of such patients (including fluoride treatments follow-up, and restorative care), are discussed. Guidelines for the dental management of edentulous patients are also presented at length (this section covers risk of bone necrosis, soft liners, timing of denture placement, dentures and preexisting bone necrosis, soft-tissue necrosis and dentures, morbidity, and prosthodontic procedures). The article concludes with a brief discussion of osteoradionecrosis and soft-tissue necrosis.

Dental Care for Persons with Disabilities↗

PubMedDate not supplied

Preradiation dental extractions and the incidence of bone necrosis.

Studies were done with 120 patients submitting to preradiation dental extraction within the radiation treatment volume. Bone necroses developed at the extraction sites in 17 patients (14.1%). The risk of bone necrosis in these patients is primarily dependent upon the size of the radiation treatment volume, radiation dose to mandibular bone, and healing time for the extraction wounds. Of the 13 mandibular bone necroses occurring at preradiation extraction sites, only two have not responded favorably to conservative management. Our data indicates that a policy of selected tooth removal, before radiation treatment, will minimize the risk of osteoradionecrosis. Mandibular molars with advanced chronic periodontal bone loss, residing within the proposed radiation field should be considered for removal before commencement of radiation treatment.

Animals↗

PubMedDate not supplied

Postradiation dental extractions: a review of the literature and a report of 72 episodes.

This report outlines our experiences involving 72 episodes of postradiation dental extraction over an 11-year period. Bone exposures of 3 months or longer developed following 16 of the 72 postradiation extraction episodes (22%). The necrosis rate in the mandible was 29% (13 of 45) and in the maxilla was 11% (3 of 27). The risk of bone necrosis increased when the dose to bone exceeded 6,500 rad, and when 75% or more of the body of the mandible was within the radiation treatment volume. Five of the 13 mandibular bone necroses precipitated by postradiation extractions eventually required radical resection of the affected portion of the mandible. The remaining eight mandibular episodes healed with conservative measures. When possible, given the two above conditions, root canal therapy rather than dental extraction should be employed to resolve mandibular dental infection within the radiation field after radiotherapy.

Dose-Response Relationship, Radiation↗

PubMedDate not supplied

Osteoradionecrosis: predisposing factors and outcomes of therapy.

Eighty-three episodes of osteoradionecrosis are reported. Of those episodes affecting the mandible (78), 23 (29.5%) required radical resection. The most common precipitating factors were postradiation extractions (22/83), periodontal disease (19/83), and preradiation extractions (17/83). Those episodes initially located within the zone of attached mucosa fared well with conservative measures while those initially located beyond the zone of attached mucosa fared poorly. In bone necroses where the external radiation dose to the affected bone exceeded 7,000 rad, the mandibular resection rate was high (44%). The most effective way of resolving advanced bone necroses was achieved with a course of hyperbaric oxygen therapy combined with a surgical sequestrectomy.

Combined Modality Therapy↗

PubMedDate not supplied

Advances in osseointegrated implants for dental and facial rehabilitation following major head and neck surgery.

Osseointegrated implants can be used to facilitate retention stability and support for facial and intraoral prostheses used to restore head and neck defects. Preliminary studies indicate that in nonirradiated maxillectomy patients the success rates are about 75%. In the reconstructed mandible the results appear to be more favorable--over 90% for implants placed in free nonvascularized bone grafts and over 90% for free revascularized bone grafts. Similar high success rates have been observed for most sites used to support facial prostheses. Success rates for auricular sites exceed 95% and for floor of nose sites success rates exceed 90%. Success rates have been lower (77%) for implants placed in the frontal bone for retention of orbital prostheses. Success rates for irradiated bone sites have been lower and range from 60.4% in the maxilla to 68.6% in facial bone sites. Of greater concern is that most implants placed in irradiated sites are beginning to show signs of impending failure.

Combined Modality Therapy↗