Fixation of zygomatic fractures with a biodegradable copolymer osteosynthesis system: short- and long-term results.

Biodegradable osteosynthesis devices can be viewed as addition to, not yet replacement for conventional metal osteosynthesis materials. In a series of 65 patients with zygomatic fractures, a short-term complication/sequelae rate of 22.8% and a long-term complication rate of 9.4% were recorded. Lactosorb plates, panels and screws were the only devices used for osteosynthesis. All complications associated with the biodegradable material could be considered minor and were resolved by the use of minor surgical procedures or conservative measures. The results of this study indicate that treatment of zygomatic fractures with biodegradable osteosynthesis material has no major long-term adverse effects beyond the total material resorption time.

Radiation therapy in hyperbaric oxygen for head and neck cancer at Royal Adelaide Hospital--1964 to 1980.

This report describes experience with radiation therapy in hyperbaric oxygen in 201 patients with squamous carcinoma arising in the mobile portion of tongue (anterior 2/3), oropharynx, hypopharynx, and supraglottic larynx, treated between the years 1964 and 1980. Although not statistically different, the overall 5-year determinate survival figures of 35% for all patients with tumors arising in the hypopharynx, 87.5% for Stage I and II, 55% for Stage III, and 27.1% for Stage IV supraglottic carcinoma were perceptibly better than those obtained in a contemporary but not randomly controlled series of patients treated in air at Royal Adelaide Hospital from 1970 to 1980. The results obtained for tumors arising in the oropharynx and mobile portion of tongue however were found to be very similar to those achieved in air. The results achieved in this series are discussed in the context of experience at other centers and the role of randomly controlled clinical studies in evaluating new treatment modalities is emphasized.

Evaluation of risk of injury to the inferior alveolar nerve with classical sagittal split osteotomy technique and proposed alternative surgical techniques using computer-assisted surgery.

Neurosensory disturbance after sagittal split osteotomy is a common complication. This study evaluated the course of the mandibular canal at three positions using computed tomography (CT), assessed the risk of injury to the inferior alveolar nerve in classical sagittal split osteotomy, based on the proximity of the mandibular canal to the external cortical bone, and proposed alternative surgical techniques using computer-assisted surgery. CT data from 102 mandibular rami were evaluated. At each position, the distance between the mandibular canal and the inner surface of the cortical bone was measured; if less than 1mm or if the canal contacted the external cortical bone it was registered as a possible neurosensory compromising proximity. The course of each mandibular canal was allocated to a neurosensory risk or a non-neurosensory risk group. The mandibular canal was in contact with, or within 1mm of, the lingual cortex in most positions along its course. Neurosensory compromising proximity of the mandibular canal was observed in about 60% of sagittal split ramus osteotomy sites examined. For this group, modified classic osteotomy or complete individualized osteotomy is proposed, depending on the position at which the mandibular canal was at risk; they may be accomplished with computer-assisted navigation.