We discuss the clinical manifestations of bisphosphonate-related necrosis of the jaw (BRONJ), and the benefits of surgical intervention in the patients. The subjects were 57 patients who were given a diagnosis of BRONJ in the Department of Oral and Maxillofacial Surgery, Dokkyo Medical University Hospital between January 2007 and January 2014. The patients comprised 17 males and 40 females, with a mean age of 72.2 years. BRONJ developed after tooth extraction or spontaneous tooth dropout in 25 patients, under a denture decubital ulcer in 11 patients, at the site of severe marginal periodontitis in 8 patients, at the site of apical periodontitis in 4 patients, after surgical removal of the mandibular torus in 2 patients, and at the site of peri-implantitis in 1 patient. However, in 6 patients, the specific causes of BRONJ could not be determined. The lesion site was the posterior part of the mandible in 31 patients, the posterior part of the maxilla in 16 patients, the anterior part of the mandible in 12 patients, and the anterior part of the maxilla in 9 patients. Bisphosphonates (BPs) were given to treat primary osteoporosis (17 patients), steroid-induced osteoporosis (15 patients), and malignant tumors (25 patients). Among the patients who were receiving oral BPs, the duration of BP administration was less than 3 years in 8 patients, 3 years to less than 5 years in 7 patients, 5 years or more in 12 patients, and unknown in 6 patients. Among the patients who were receiving intravenous BPs, the duration of BP administration was less than 3 years in 17 patients, 3 years to less than 5 years in 3 patients, 5 years or more in 2 patients, and unknown in 2 patients. Among the 57 patients with BRONJ, 18 (31.6%) had a good response to conservative treatment alone, but 39 (68.4%) did not respond to conservative treatment. Of these 39 patients, 27 (all stage II) underwent surgical intervention. The surgical procedure was removal of the infected bone in 24 patients, and marginal osteotomy in 3 patients. Of the 27 patients who underwent surgery, 25 (93%) improved after surgical intervention, but 2 patients (7%), who were receiving zoledronic acid for malignant tumors, did not have good results. Among patients with BRONJ who initially receive conservative treatment, but do not have good results, surgical intervention at an appropriate time may improve disease outcomes.

Odontoameloblastoma is a rare mixed odontogenic tumor, characterized by the simultaneous occurrence of an ameloblastoma and a compound or complex odontoma in the same tumor mass.

　We report a case of odontoameloblastoma arising in the maxillary molar region of a 33-year-old man. The patient presented with a chief complaint of swelling with dull pain of the left cheek. Radiographic examination showed slight sinus enlargement and a unilocular radiolucent area with calcified structures resembling mature tooth in the left maxillary sinus. The lesion progressed into the left maxillary sinus through the thin bone wall, elevating the floor of the sinus. In addition, an impacted tooth contiguous with the lesion was observed. The left second premolars and left first and second molars presented with root resorption. The tumor was enucleated in a single mass, along with the impacted teeth, with the patient under general anesthesia. The histopathological diagnosis was an odontoameloblastoma. The patient’s prognosis remains good as of 4 years 6 months after the operation.

We report a case of suspected familial white sponge nevus of the oral mucosa. A 38-year-old woman was referred to our department because of white lesions presenting bilaterally on the buccal mucosa. Biopsy of the buccal mucosa revealed epithelial hyperplasia with parakeratosis and a basket-weave-like pattern. Moreover, characteristic eosinophilic perinuclear zones were observed in the vacuolated epithelial cells. On the basis of these findings, white sponge nevus was diagnosed histologically. As similar lesions were found in the oral mucosa of the patient’s two children, these lesions were suspected to be familial white sponge nevus. Currently, these patients are being followed up carefully without any treatment.

Small cell carcinoma (SmCC) arising in salivary gland is extremely rare, and most of the primary lesions occur in the parotid glands. We report a case of SmCC arising in the palatine gland in a 64-year-old man. The patient had an ulcerated tumor, measuring 35 × 20 mm, in the left side of the palate. A number of enlarged lymph nodes were recognized in the left cervical region. No distant metastases or other tumors were detected on ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT). A biopsy was performed from the palatal lesion, and the histopathological diagnosis was SmCC. The patient received radiotherapy alone, because chemotherapy had an increased risk of severe adverse events due to the presence of chronic kidney failure. Radiotherapy was administered to the left palatal and cervical regions in a total dose of 60 Gy. The tumor and the metastatic lymph nodes markedly shrank after the radiotherapy. However, 3 months later, metastatic cervical lymph nodes appeared in the right cervical region. Bony metastases to the right ilium and the left pubis were also detected on FDG-PET/CT. Additional radiotherapy was administered (60 Gy to the right cervical lymph nodes and 40 Gy to the metastatic bone lesions), but was not effective. Regrowth of the primary tumor and bilateral metastatic cervical lymph nodes appeared, and skin, lung, and liver metastases were identified. Finally, the patient died of multiple organ failure 12 months after the initial diagnosis.

We report a case of chronic obstructive sialadenitis (COS) successfully treated using a microburr^® with parotid sialendoscopy. A 48-year-old woman was referred to our hospital with a history of multiple episodes of swelling and pain in her right parotid region for 5 years. Computed tomography revealed no pathologic findings. For diagnosis and treatment, we performed sialendoscopy of the parotid gland with the patient under general anesthesia and found a severe stricture in the region of the buccinator muscle and mucus plug formation. We diagnosed COS of the right parotid gland and dilated the stricture using a sialoballoon. However, the stricture recurred 1 month later; therefore, we performed sialendoscopy again and used a microburr^® to dilate the stricture. After the operation, a stent was placed in Stensen’s duct for 6 weeks. However, the same symptoms recurred after removing it. Currently, the stent is in Stensen’s duct. There has been no evidence of recurrence after 1 year. Our patient’s course provides two important suggestions. First, a microburr^® is useful for treating COS; second, a stent has to remain in the duct for a long time to prevent stricture recurrence.

We report two cases of a mandibular third molar enclosing the inferior alveolar neurovascular bundle between the tooth roots with apical adhesion.

　A 60-year-old woman (case 1) and a 79-year-old woman (case 2) underwent third molar extraction because of right mandibular osteomyelitis and left mandibular pericoronitis, respectively. In both patients, only the occlusal surfaces of the third molars were visible on intraoral examination. Their mandibular canals and third molar roots crossed on panoramic radiography. The white line of the mandibular canal wall was unclear only in case 1, suggesting that a neurovascular bundle passed between the roots of the tooth. We recognized this anomaly on preoperative computed tomography (CT), and the neurovascular bundle was preserved by careful root separation during the extraction. In case 2, the same operative technique was used for the extraction, without performing preoperative CT. Post-extraction paresthesia in both cases was improved by vitamin B₁₂ treatment.

　It is difficult to judge such radicular malformation and the position of the neurovascular bundle on the basis of preoperative panoramic radiography alone. Therefore, more detailed investigations by CT are recommended. We highlight the importance of adequate preoperative evaluations to preserve the neurovascular bundle by carefully identifying root separation requirements during third molar extraction.

We report a case of extramedullary plasmacytoma arising in the tongue. A 79-year-old man with a localized indurative white spot on the tongue was referred to our hospital for consultation. After making a clinical diagnosis of a tongue tumor, the lesion was completely excised. Histological and immunohistochemical examinations confirmed the diagnosis of an IgG-κ type of extramedually plasmacytoma. A general examination showed no evidence of multiple myeloma. The postoperative course was uneventful, with no signs of recurrence or progression to multiple myeloma.