Oral risk factors associated with medication-related osteonecrosis of the jaw in patients with cancer.

INTRODUCTION: Bone-modifying agents (BMAs) are indispensable to cancer therapy. However, the number of patients with medication-related osteonecrosis of the jaw (MRONJ) is increasing according to the BMA administration. Oral factors predisposing to development of MRONJ are receiving attention, and oral management is recommended for prevention of MRONJ; however, the strategy and criteria have not yet been established. Therefore, we investigated the oral risk factors associated with MRONJ development in this study. MATERIALS AND METHODS: A retrospective study was carried out on 398 cancer patients who had received oncological-dose BMAs between 2007 and 2018; general health factors, demographic, and dental factors were examined along with MRONJ development in all the patients. The cumulative occurrence rate of MRONJ was calculated using a Kaplan-Meier analysis. Clinical factors were analyzed using the Cox regression analysis. RESULTS: MRONJ occurred in 42 of the 398 patients. The cumulative MRONJ incidence rates were 4.5, 12.9, 17.7, and 21.6% at 1, 2, 3, and 4 years, respectively. Age (p = 0.038), male sex (p = 0.002), initiation of dental interventions before BMA administration (p = 0.020), alveolar bone loss involving more than half the root (p < 0.001), and torus mandibularis (p < 0.001) were significantly associated with MRONJ. CONCLUSIONS: Our findings suggest that patients with alveolar bone loss involving more than half the root on panoramic radiographs and torus mandibularis carry a high risk of MRONJ development. Early dental intervention before BMA administration and oral management during the treatment are important for preventing MRONJ.

Does inflammatory dental disease affect the development of medication-related osteonecrosis of the jaw in patients using high-dose bone-modifying agents?

OBJECTIVES: High-dose bone-modifying agents (BMAs), such as bisphosphonates and denosumab, are essential for the treatment of cancer patients with bone metastases. The incidence of medication-related osteonecrosis of the jaw (MRONJ) is increasing. Inflammatory dental diseases could lead to MRONJ, and hence, they should be managed appropriately. Tooth extractions are commonly advised to prevent dental inflammation; however, the accurate indications for tooth extractions before starting BMA therapy have not been established. Hence, we assessed teeth with inflammatory dental diseases to identify indicators for prophylactic extraction before starting BMA therapy. MATERIALS AND METHODS: We included 745 teeth with inflammatory dental diseases of 212 cancer patients on high-dose BMA therapy. We assessed the relationship between inflammatory dental disease and risk of MRONJ development. Multivariate Cox regression analysis was used for statistical analysis. The cumulative occurrence rate of MRONJ was calculated using the Kaplan-Meier method. RESULTS: MRONJ occurred in 43 of 745 teeth. Teeth characteristics significantly correlated with MRONJ occurrence were mandible (p = 0.009), molar region (p = 0.005), radiopaque changes in bone surrounding the root on orthopantograms obtained at patients' first visits (p < 0.001), and tooth extractions after starting BMA therapy (p < 0.001). CONCLUSIONS: Radiopaque changes in bone surrounding the root are an important radiographic finding that indicates the need for prophylactic tooth extractions before starting BMA therapy. CLINICAL RELEVANCE: Our results suggest that the prophylactic extraction of teeth with radiopaque changes in bone surrounding the root before starting BMA therapy could prevent the onset of MRONJ.

Bite injuries caused by transcranial electrical stimulation motor-evoked potentials' monitoring: incidence, associated factors, and clinical course.

PURPOSE: The incidence of bite injuries associated with transcranial electrical stimulation motor-evoked potentials monitoring reportedly ranges from 0.13 to 0.19%. However, in clinical practice, bite injuries appear to occur more frequently than previously reported. Our aim was to identify the incidence of and perioperative risk factors associated with bite injuries caused by transcranial electrical stimulation motor-evoked potential monitoring. METHODS: Patients who underwent elective surgery with transcranial electrical stimulation motor-evoked potential monitoring at a single tertiary hospital in Japan between June 2017 and December 2017 were included in this study. All patients were assessed by oral surgeons preoperatively and postoperatively. The associated factors with bite injuries were explored by the univariate analysis. RESULTS: 12 of 186 patients experienced 13 bite injuries, including three lip, six oral mucosa, and four tongue injuries. No patient required suture repair. 11 of 12 patients had uneventful postoperative courses and were cured within 12 postoperative days. One patient with a tongue ulcer and a hematoma had difficulty in oral intake and persistent dysgeusia. Patient severe movement during transcranial electrical stimulation motor-evoked potential monitoring was associated with bite injuries (p = 0.03). CONCLUSIONS: The incidence of bite injuries assessed by oral surgeons was 6.5% in patients with transcranial electrical stimulation motor-evoked potential monitoring, and the patients with severe movement during the monitoring tended to incur bite injuries. In rare cases, transcranial electrical stimulation motor-evoked potential monitoring may cause difficulty in oral intake and dysgeusia.