The World Health Organization reported that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission is caused by respiratory droplets and aerosols from the oral cavity of infected patients. The angiotensin-converting enzyme 2 (ACE2) is considered the host functional protein for SARS-CoV-2 infection. In this article, we first revealed that the positive proportion of ACE2 expression in gingival cells collected from the gingival sulcus was increased to the same level as the tongue. Our data demonstrate that cells in the gingival sulcus may be a new entry point for the SARS-CoV-2 virus via a high expression of ACE2. In addition, we first evaluated the expression of ACE2 in various sites of the oral cavity with noninvasive, convenient liquid-based cytology. The liquid-based cytology evaluation of oral tissue may provide a novel preventive medical avenue against COVID-19.

This single-center retrospective observational study aimed to identify risk factors for developing denosumab-related osteonecrosis of the jaw (DRONJ) in stage IV solid cancer patients with bone metastases. In total, 123 consecutive patients who had received 120 mg of denosumab every 4 weeks at least twice between July 2014 and October 2018 were included. We surveyed their demographics, medical history, blood test, underlying disease, and intraoral findings. Fourteen patients (11.4%) developed DRONJ within a mean denosumab administration period of 4 months (range: 2–52 months). Univariate analyses showed a statistically significant correlation between DRONJ and hormone therapy, chemotherapy/molecular target drug, apical periodontitis, periodontal disease, sex and body mass index. Multivariate analysis showed a statistically significant correlation between DRONJ and hormone therapy (odds ratio [OR], 22.07; 95% confidence interval [CI], 2.86–170.24), chemotherapy and/or molecular targeted therapy (OR, 18.61; 95% CI, 2.54–136.27), and apical periodontitis (OR, 22.75; 95% CI, 3.20–161.73). These findings imply that collaborative oral examinations by oral specialists may reduce the risk of development of DRONJ in patients treated with denosumab for bone metastases from solid cancers.

Two second-generation PLLA/PGA bioresorbable osteosynthetic plate systems for oral and maxillofacial surgery are available in Japan. The two systems have different PLLA-PGA component ratios (RapidSorb^®, 85:15; Lactosorb^®, 82:18) and plate and screw shapes. We conducted a retrospective study to compare our clinical evaluation and examine the incidence of postoperative complications between the two plate systems. A retrospective survey was conducted in 148 patients (midfacial fracture/trauma (68.2%) and dentofacial deformity patients (31.8%); males (54.7%); median age, 37.5 years) treated using maxillofacial osteosynthetic plate systems. The complications included plate exposure (7.4%), infection, (2.7%), and plate breakage (0.7%). Multivariate logistic regression analysis showed a significant correlation between sex (female), plate system (Lactosorb^®), number of plates, and pyriform aperture and periorbital sites of plate placement (p < 0.05). Additionally, the propensity score-adjusted model showed a significant correlation between Lactosorb^® and postoperative complications (odds ratio 1.007 (95% confidence interval, 1.001–1.055), p < 0.01). However, the two plate systems showed a low incidence rate of complications, and the plate integration and survivability were similar using 2.0-mm or 1.5-mm resorbable plate regardless of the plate system. Our findings suggest that female sex and a greater number of plates are risk factors for postoperative complications, whereas pyriform aperture and periorbital plate placements reduce the risk.

A few studies have provided detailed reports suggesting that subjective swallowing disorders may be related to dysphagia. Therefore, we verified the relationship between oral health-related self-efficacy and dysphagia severity in cancer treatment using a cross-sectional study. Participants included patients undergoing treatment for cancer at Shimane University Hospital in Shimane, Japan, and those receiving outpatient treatment at the hospital’s Oral Care Center between August 2018 and April 2019. In all, 203 participants enrolled in the study and completed the Functional Oral Intake Scale (FOIS), the Self-efficacy Scale for Advanced Cancer (SEAC), and the Oral Health-related Self-Efficacy Scale for Patients with Cancer (OSEC). Multivariate analysis showed a statistically significant correlation between the low FOIS score and the SEAC subscales of Activities of Daily Living Self-efficacy (ADE) (odds ratio 1.04, 95% [CI] 1.00–1.07) and Symptom Coping Self-efficacy (SCE) (odds ratio 0.61, 95% [CI] 0.42–0.88). Based on the Jonckheere-Terpstra test, the SEAC and the OSEC tended to increase as the category of the FOIS progressed. To conclude, self-efficacy played an important role in dysphagia and may affect the severity of dysphagia in cancer patients.

Currently, there is no scale to subjectively assess postoperative oral dysfunction in patients with oral cancer. The purpose of this study was to evaluate the reliability and validity of the Postoperative Oral Dysfunction Scale (POD-10) that we developed. Between September 2019 and August 2021, 62 eligible oral cancer patients (median age, 72 years; 42 men and 20 women) were enrolled in the study. The Cronbach’s alpha coefficient, which indicates the internal consistency of the scale, was 0.94, and the intraclass correlation coefficient, which indicates reproducibility, was 0.85 (95% confidential interval: 0.40–0.96, p < 0.05). Concurrent validity testing showed a statistically significant correlation between POD-10 and Eating Assessment Tool (EAT-10) (r = 0.89, p < 0.05). To test discriminant validity, statistically significant differences were found between early-stage cancer (stage I and II) and advanced-stage cancer (stage III and IV) (p < 0.05). Twenty-four points were calculated as the cutoff value for POD-10 using receiver operating characteristic analysis to calculate the cutoff value. The POD-10 was shown to be a clinically reliable and valid scale that can be used to subjectively assess postoperative oral dysfunction in patients with oral cancer and is expected to be used as a simple diagnostic tool.