A case of medication-related osteonecrosis of the jaw successfully treated with hyperbaric oxygen therapy and sequestrectomy

Abstract

We report a case of medication-related osteonecrosis of the jaw successfully treated with hyperbaric oxygen therapy（ HBO） and sequestrectomy. The patient was a 60-year-old male who was referred to our department for an examination of bone exposure of the left mandible. The patient's medical history revealed prostate cancer with multiple bone metastases, and the skeletalrelated events were treated by subcutaneous injection of 120 mg of denosumab per month for two years and eight months. Intraoral findings revealed alveolar bone exposure on the lingual side of the left mandible. The gingiva surrounding the exposed bone was erythematous with pus discharge. Conservative therapy with local irrigation was commenced; however, the area of exposed bone gradually increased. Eventually, the necrotic bone separated from the mandible began to mobilize, and sequestrectomy was then performed under local anesthesia. However, the gradual increase in the size of the exposed bone could not be controlled. Furthermore, phlegmon of the left cheek developed. Therefore, HBO was commenced, and 10 HBO sessions improved the left cheek swelling with an increase in the maximum mouth opening from 25 to 30 mm. Panoramic radiograph findings revealed that the necrotic bone separated from the mandible. After eight additional HBO sessions, sequestrectomy was performed under general anesthesia. As a result, the wound in the mandible healed completely with epithelialization in two months. Two years and 6 months after the operation, no relapse of mandibular osteomyelitis was observed. In addition, further bone metastasis from the prostate cancer had been controlled by oral administration of an anti-androgenic hormone.