Treatment of mandibular osteoradionecrosis by cancellous bone grafting.

PURPOSE: This study was undertaken to evaluate a new method in the treatment of mandibular osteoradionecrosis. PATIENTS AND METHODS: Eight patients, seven male and one female, with a mean age of 64 years (range, 43 to 67 years), suffering from osteoradionecrosis of the mandible, two bilaterally and six unilaterally, were treated. Five initially had hyperbaric oxygen (HBO) followed by sequestrectomy, and three had sequestrectomy alone. Because healing failed to occur, all patients were treated by removal of the necrotic bone in the affected part of the mandible and filling the defect with compressed particulated cancellous bone and marrow from the tibia. The patients were observed for an average period of 39 months (range, 20 to 93 months). RESULTS: Primary healing was achieved in two patients with unilateral osteoradionecrosis and HBO treatment. In another patient treated with HBO primary healing occurred on one side while the other healed secondarily. In the remaining five patients, complete secondary healing took place, but it was complicated in three patients by fistulas, two of which were associated with fractures of the mandibular body. The fistulas were excised, and complete healing of the soft tissues occurred, but the fractures resulted in pseudarthrosis. CONCLUSIONS: The technique presented in this study can be useful in the treatment of osteoradionecrosis as an alternative to continuity resection and reconstruction with free osteocutaneous flaps, but, whenever possible, it should be proceeded by HBO treatment.

Dental implant survival in the irradiated jaw: a preliminary report.

Seventeen oral cancer patients (47 to 78 years, mean 67) were treated with external radiation in areas that included future implant sites. Implants were placed in the irradiated jaws after a period of 18 to 228 months (mean 88 months). The patients received 103 implants and were followed for 1 to 62 months (mean 21 months) after implant loading. The cumulative survival rate of the implants after 1 year was 97% in the mandible and 92% in the maxilla. While the irradiation dose used did not affect implant survival, this result may possible be influenced by the addition of hyperbaric oxygen treatment for patients receiving more than 50 Gy. Irradiation for treatment of oral cancer does not seem to reduce the survival rate of implants as compared to those placed in the nonirradiated jaw.

Clonal chromosome aberrations accumulate with age in upper aerodigestive tract mucosa.

Short-term cultured non-neoplastic upper aerodigestive tract (UAT) mucosa samples from 36 patients with squamous cell carcinoma of the head and neck (SCC) and 53 patients with benign UAT disorders were cytogenetically analyzed. The cell cultures were divided into two series: in series A, cells were cultured in a medium stimulating outgrowth of mesenchymal cells; whereas the cultured cells in series B were of epithelial morphology. Series A was further subdivided into three different age groups (< or = 15 years, 16-59 years, and > or = 60 years) of non-SCC patients and one SCC group. Series B was composed of two groups; one with and one without SCC. Among the non-SCC patients in series A, there was an increase with age in the frequency of cells/sample with numerical and structural chromosomal changes as well as in the incidence of clonal chromosomal aberrations. No differences could, however, be detected between cancer patients and age-matched controls. In series B, the frequency of cells/sample with numerical changes and the incidence of clonal numerical aberrations were significantly higher among SCC patients. Three main conclusions could be drawn. First, the frequencies of clonal and non-clonal chromosome aberrations in UAT mucosa were age dependent. Second, the cytogenetic support for the validity of the field cancerization hypothesis was restricted to increased levels of numerical chromosome changes in epithelial cell cultures from cancer patients. Third, clonal chromosome aberrations, including autosomal and sex chromosome aneuploidies as well as structural rearrangements, are not restricted to neoplastic mucosal cells.

Immediate placement of implants into extraction sockets: implant survival.

In 51 patients (21 males and 30 females) aged 16 to 72 years, a total of 109 Nobelpharma implants were placed into extraction sockets immediately following extraction. The follow-up period varied between 1 and 67 months with a mean of 30.5 months. Osseointegration was determined by clinical stability, lack of symptoms, and lack of peri-implant pathology based on radiographic examination. The implant survival rate was 93.6%. Six implants were mobile at the abutment connection stage, and one was lost when function commenced. The success rate was 92.0% for implants replacing teeth extracted because of periodontitis and 95.8% for implants replacing teeth extracted for other reasons. Two other complications occurred: 12 cover screws perforated the gingiva during healing; and infection developed in five cases. The incidence of infection was higher in the periodontitis group. It was found that immediate placement of implants into extraction sockets is a safe and predictable procedure if certain guidelines are followed.