Background Adverse events are increasingly being reported with the growing COVID-19 vaccination rate. However, the current literature on orofacial adverse effects following COVID-19 vaccination are severely limited. With the continuation of the global vaccination campaign the incidence of oral adverse effects will inevitably increase. Case presentation Clinical characteristics and treatment results of nine patients who complained of pain and discomfort of the oral cavity following SARS-CoV-2 vaccination were analyzed. Swelling and pain of the posterior palatal area, pain on palatal area of the central incisor, pain on the mucosa of the lip and lower gingiva, right preauricular region and right posterior lower gingiva, the buccal mucosa, tongue, and the right lower second molar area were the reported symptoms. Ulceration and swelling of the oral mucosa were found in certain cases. The symptoms were generally mild and responded well to medication within a relatively short period of time. Conclusion Oral adverse reactions following COVID-19 vaccination were manageable with treatment. Clinicians should understand the true nature of orofacial adverse reactions following COVID-19 vaccines and guide patients in decision-making.

The aim of this study is to investigate the differences in polysomnographic and cephalometric features according to positional and rapid eye movement (REM) sleep dependencies in obstructive sleep apnea patients. Standard polysomnography and cephalometric analyses were performed on 133 OSA patients. The subjects were categorized into positional and non-positional, and REM-related and not-REM-related OSA groups according to positional and REM sleep dependency on severity of sleep apnea. Polysomnographic and cephalometric parameters were compared between groups. Positional and REM-related OSA patients showed significantly lower non-supine apnea–hypopnea index (AHI), non-REM (NREM) AHI and overall AHI and higher NREM oxygen saturation (SpO2) and mean SpO2 compared to non-positional and not-REM-related OSA patients, respectively. Cephalometric features between positional and non-positional OSA patients did not show any significant differences. However, REM-related OSA patients showed significantly larger inferior oral airway space and shorter perpendicular distance between mandibular plane and anterior hyoid bone and the distance between uvula and posterior nasal spine, and narrower maximum width of soft palate than not-REM-related OSA patients. Positional and REM-related OSA patients have lower severity of sleep apnea, suggesting the possibility of lower collapsibility of the upper airway. REM sleep dependency was associated with anatomical factors, while positional dependency did not show such a tendency.

The purpose of this study was to compare the differences in clinical signs and symptoms, and psychological profiles of temporomandibular joint osteoarthritis (TMJ OA) between juvenile and adult patients.Methods: Two-hundred eighty-three TMJ OA patients who visited the Orofacial Pain Clinic of Seoul National University Dental Hospital were classified by juvenile (153 patients; mean age 14.2±1.7 years, range 9-16 years) and adult (130 patients; mean age 34.0±2.8 years, range 30-40 years) groups, and compared the clinical symptoms based on the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) axis I guidelines including Graded Chronic Pain (GCP) scale, mandibular range of motion, and the associated symptoms. Psychological profiles were also evaluated using the Symptom Checklist 90-Revision (SCL-90-R).Results: Juvenile patients reported lower pain intensity and a lower prevalence of headache and clenching than adult patients. Their mandibular range of motion was also higher than adult patients. Juvenile patients showed a lower percentage of patients with T-score above 50 in somatization (SOM), obsessive-compulsive (O-C), interpersonal sensitivity (I-S), and paranoid ideation (PAR) than adults. Based on the GCP scale, the percentage of the high disability group was lower in juveniles. Conclusions:Juvenile TMJ OA patients generally showed milder clinical symptoms than adults. Adult patients showed higher prevalence of psychological problems and higher disability than juvenile patients. Age should be considered in evaluation and treatment of TMJ OA patients to achieve better treatment results and understanding its pathophysiology.

Mandibular advancement devices (MAD) are used effectively and widely for the treatment of obstructive sleep apnea (OSA) and rapid-eye-movement (REM) dependency of the patients can affect the treatment outcome of OSA. The aim of this study was to compare treatment outcomes of MAD between REM-related and not-REM-related OSA patients.Methods: Fifty-six consecutive patients with OSA who received MAD therapy were evaluated using full night polysomnography before and after insertion of the MADs. The patients were divided into REM-related (REM apnea-hypopnea index [AHI] at least two times higher than their non-REM AHI) and not-REM-related (REM AHI less than two times higher than their non-REM AHI) OSA groups.Results: MAD is used for the treatment of OSA effectively. In respect of AHI, MAD therapy were effective both in REM-related OSA and not-REM-related OSA, but MAD therapy was more effective in not-REM-related OSA than REM-related OSA in overall sleep and non-REM sleep. SpO 2 saturations were improved after MAD therapy, but were not different between two groups. Epworth sleepiness scale scores were not improved after MAD therapy. Percentage of REM sleep was increased after MAD therapy but was not different between two groups.Conclusions: MAD therapy was more effective in not-REM-related OSA than REM-related OSA and REM dependency can be a predictive factor of treatment outcome of oral appliance for OSA patients.