Expression of JCAD and EGFR in Perineurial Cell-Cell Junctions of Human Inferior Alveolar Nerve.

Although perineurium has an important role in maintenance of the blood-nerve barrier, understanding of perineurial cell-cell junctions is insufficient. The aim of this study was to analyze the expression of junctional cadherin 5 associated (JCAD) and epidermal growth factor receptor (EGFR) in the perineurium of the human inferior alveolar nerve (IAN) and investigate their roles in perineurial cell-cell junctions using cultured human perineurial cells (HPNCs). In human IAN, JCAD was strongly expressed in endoneurial microvessels. JCAD and EGFR were expressed at various intensities in the perineurium. In HPNCs, JCAD was clearly expressed at cell-cell junctions. EGFR inhibitor AG1478 treatment changed cell morphology and the ratio of JCAD-positive cell-cell contacts of HPNCs. Therefore, JCAD and EGFR may have a role in the regulation of perineurial cell-cell junctions.

Referral to Pain Specialists for Treatment of Intractable Mandibular Pain Caused by Osteonecrosis of the Jaw: A Case Series Report.

Pain is a problematic symptom in patients with osteonecrosis of the jaws (ONJ). Effective pain management in patients with advanced ONJ still remains an unresolved issue. This case series report presents three patients who were referred to the pain clinic for treatment of intractable pain caused by ONJ. Two patients received mandibular nerve blocks and achieved pain relief. After referral to the pain clinic, these two patients underwent segmental mandibulectomy for ONJ. In the third patient, the effect of pain control was limited. Appropriate cooperation between the oral and maxillofacial surgeon and the pain specialist is essential for pain management in patients with advanced ONJ who experience intense pain.

Risk factors for osteoradionecrosis of the jaw in patients with head and neck squamous cell carcinoma.

BACKGROUND: To evaluate factors associated with osteoradionecrosis of the jaw (ORNJ) in patients with head and neck squamous cell carcinoma (HNSCC), focusing on jaw-related dose-volume histogram (DVH) parameters. METHODS: We retrospectively reviewed the medical records of 616 patients with HNSCC treated with curative-intent or postoperative radiation therapy (RT) during 2008-2018. Patient-related (age, sex, history of smoking or alcohol use, diabetes mellitus, performance status, pre-RT dental evaluation, pre- or post-RT tooth extraction), tumor-related (primary tumor site, T-stage, nodal status), and treatment-related (pre-RT surgery, pre-RT mandible surgery, induction or concurrent chemotherapy, RT technique) variables and DVH parameters (relative volumes of the jaw exposed to doses of 10 Gy-70 Gy [V10-70]) were investigated and compared between patients with and without ORNJ. The Mann-Whitney U test was used to compare RT dose parameters. Univariate and multivariate Cox regression analyses were used to assess factors associated with ORNJ development. Kaplan-Meier analyses were performed for cumulative ORNJ incidence estimation. RESULTS: Forty-six patients (7.5%) developed ORNJ. The median follow-up duration was 40 (range 3-145) months. The median time to ORNJ development was 27 (range 2-127) months. DVH analysis revealed that V30-V70 values were significantly higher in patients with than in those without ORNJ. In univariate analyses, primary tumor site, pre-RT mandible surgery, post-RT tooth extraction, and V60 > 14% were identified as important factors. In multivariate analyses, V60 > 14% (p = 0.0065) and primary tumor site (p = 0.0059) remained significant. The 3-year cumulative ORNJ incidence rates were 2.5% and 8.6% in patients with V60 ≤ 14% and > 14%, respectively (p < 0.0001), and 9.3% and 1.4% in patients with oropharyngeal or oral cancer and other cancers, respectively (p < 0.0001). CONCLUSIONS: V60 > 14% and oropharyngeal or oral cancer were found to be independent risk factors for ORNJ. These findings might be useful to minimize ORNJ incidence in HNSCC treated with curative RT.

Effect of educational intervention on the appropriate use of oral antimicrobials in oral and maxillofacial surgery: a retrospective secondary data analysis.

BACKGROUND: In Japan, oral third-generation cephalosporins with broad-spectrum activity are commonly prescribed in the practices of dentistry and oral surgery. However, there are few reports on the appropriate use of antibiotics in the field of oral surgery. This study aimed to evaluate the appropriateness of antibiotic use before and after an educational intervention in the Department of Oral and Maxillofacial Surgery, Kobe University Hospital. METHODS: The use of oral antibiotics was investigated among inpatients and outpatients before and after an educational intervention conducted by the antimicrobial stewardship team. Additionally, the frequency of surgical site infection after the surgical removal of an impacted third mandibular molar under general anesthesia and the prevalence of adverse effects of the prescribed antibiotics were comparatively evaluated between 2013 and 2018. RESULTS: After the educational intervention, a remarkable reduction was noted in the prescription of oral third-generation cephalosporins, but increased use of penicillins was noted among outpatients. There was reduced use of macrolides and quinolones in outpatients. Although a similar trend was seen for inpatients, the use of quinolones increased in this population. Despite the change in the pattern of antibiotic prescription, inpatients who underwent mandibular third molar extraction between 2013 and 2018 did not show a significant increase in the prevalence of surgical site infections (6.2% vs. 1.8%, p = .336) and adverse effects of drugs (2.1% vs. 0%, p = .466). CONCLUSIONS: This study suggests that the judicious use of oral antibiotics is possible through conscious and habitual practice of appropriate antibiotic use. However, further investigation is required to develop measures for appropriate use of oral antibiotics.