Medication-Related Osteonecrosis of the Jaw

Osteonecrosis of the jaw (ONJ) is a common side effect of antiresorptive drugs that are administered to cancer patients for bone metastasis, multiple myeloma, and osteoporosis. Since both bisphosphonate (BP) and denosumab show anti-bone resorption effects with ONJ, antiresorptive agent-related ONJ (ARONJ) has been suggested as a comprehensive term encompassing both BP-related osteonecrosis of the jaw (BRONJ) and denosumab-related osteonecrosis of the jaw (DRONJ). The term medication-related osteonecrosis of the jaw (MRONJ) is proposed as ARONJ with the antiangiogenic inhibitors or molecularly targeted drugs-related ONJ. Suppression of bone remodeling may contribute to the development of osteonecrosis and results in inadequate osteoclast activity to allow healing of the extraction socket. Infection is a major factor in the development of MRONJ. The major treatment goals for patients at risk of developing or who have MRONJ are prioritization and support of continued oncologic treatment in patients receiving antiresorptive and antiangiogenic therapy. To minimize the development of MRONJ in patients at risk, regular dental examinations are encouraged. Oral hygiene should be improved and local infection is managed as early as possible. The use of antibiotics before and after oral surgical procedures has been demonstrated to lower the risk of MRONJ

口腔がん関連microRNAの総合的機能解析と新規治療法の探索

科学研究費助成事業 研究成果報告書：基盤研究(B)2015-2017課題番号 : 15H0503

ヌードラット末梢神経損傷に対するヒト歯髄幹細胞の神経再生効果

科学研究費助成事業 研究成果報告書：挑戦的萌芽研究2016-2017課題番号 : 16K1581

Proton Beam Therapy for Ameloblastic Carcinoma of the Maxilla: Report of a Rare Case

Ameloblastic carcinoma (AC) is a rare malignant odontogenic tumor that combines the histologic features of ameloblastoma with those of cytologic atypia. The standard treatment for this lesion is wide local excision. Proton beam therapy (PBT) can deliver high irradiation doses to the target and avoid irradiation to surrounding normal tissues, but no reports of PBT for AC have been published thus far. This report describes the case of a 70-year-old woman with a pathologic diagnosis of maxillary AC who refused surgical resection and received hypofractionated PBT at a total dose of 69 Gy in 23 fractions. She has been alive for more than 5 years after PBT without any evidence of recurrence and side effects. This is the first reported case of successful treatment after curative radiation therapy for maxillary AC

Suitable Ovariectomy Age for Screening the Functional Agents by Femoral Bone Strength in Osteoporosis Model Rats

Abstract Osteoporosis is a major contributor to the high frequency of bone fracture in elderly women. The ovariectomized (OVX) rat is one of the excellent pre-clinical animal model of osteoporosis. Following ovariectomy, rapid loss of cancellous bone mass and strength occurs. Maximum breaking force of the femoral diaphysis is a major parameter to determine the severity of the osteoporosis directly. Although, the suitable age at ovariectomy remains obscure to evaluate the maximum breaking force of the femoral diaphysis. Accordingly, the suitable rat age at ovariectomy to evaluate the maximum breaking force of the femoral diaphysis for screening of therapeutic or functional agents was determined. Female Sprague-Dawley rats (6, 13 or 30 week-old) were used. Rats of each age were divided into two groups; underwent bilateral OVX and underwent bilateral laparotomy (sham). All rats were fed an AIN93G-based normal diet for further 10 weeks. Reduction of maximum bone strength in femur and increase of body weight gain were observed only in 6 week-old OVX rats after 10-week acclimatization, whereas the difference was obscure in 13 and 30 week-old OVX rats. Therefore, ovariectomy at 6 week-old was the suitable age for osteoporosis model to screen the effects of functional agents in rats

Exercise habituation is effective for improvement of periodontal disease status: a prospective intervention study

Background and purpose: Periodontal disease is closely related to lifestyle-related diseases and obesity. It is widely known that moderate exercise habits lead to improvement in lifestyle-related diseases and obesity. However, little research has been undertaken into how exercise habits affect periodontal disease. The purpose of this study was to examine the effect of exercise habits on periodontal diseases and metabolic pathology.Methods: We conducted a prospective intervention research for 12 weeks. The subjects were 71 obese men who participated in an exercise and/or dietary intervention program. Fifty subjects were assigned to exercise interventions (exercise intervention group) and 21 subjects were assigned to dietary interventions (dietary intervention group). This research was conducted before and after each intervention program.Results: In the exercise intervention group, the number of teeth with a probing pocket depth (PPD) ≥4 mm significantly decreased from 14.4% to 5.6% (P<0.001), and the number of teeth with bleeding on probing (BOP) significantly decreased from 39.8% to 14.4% (P<0.001). The copy counts of Tannerella forsythia and Treponema denticola decreased significantly (P=0.001). A positive correlation was found between the change in the copy count of T. denticola and the number of teeth with PPD ≥4 mm (P=0.003) and the number of teeth with BOP (P=0.010). A positive correlation was also found between the change in the copy count of T. denticola and body weight (P=0.008), low-density lipoprotein cholesterol (P=0.049), and fasting insulin (P=0.041). However, in the dietary intervention group the copy count of T. denticola decreased significantly (P=0.007) and there was no correlation between the number of periodontal disease-causing bacteria and PPD and BOP.Conclusion: Our results are the first to show that exercise might contribute to improvements in periodontal disease

Monitoring of circulating tumour-associated DNA as a prognostic tool for oral squamous cell carcinoma

Frequent allelic imbalances (AIs) including loss of heterozygosity and microsatellite instability on a specific chromosomal region have been identified in a variety of human malignancies. The objective of our study was to assess the possibility of prognostication and monitoring of oral squamous cell carcinoma (SCC) by microsatellite blood assay. DNA from normal and tumorous tissues and serum DNA obtained at three time points (preoperatively, postoperatively, and 4 weeks postoperatively) from 64 patients with oral SCC was examined at nine microsatellite loci. In all, 38 (59%) DNA samples from tumorous tissues and 52% from serum showed AIs in at least one locus. Patterns of AIs in the serum DNA were matched to those detected in tumour DNA. Of them, AIs were frequently detected preoperatively (44%, 28 of 64), and postoperatively (20%, 13 of 64). Moreover, among 12 cases with AIs during the postoperative period, six had no evidence of an AI 4 weeks postoperatively, and they had no recurrence and were disease free. In contrast, six patients with AI-positive DNA 4 weeks postoperatively have died with distant metastasis within 44 weeks. Thus, our results suggest that the assessment of microsatellite status in the serum DNA could be a useful predictive tool to monitor disease prognosis