Purpose: Placing dental implants in areas with low bone density or in conditions where bone healing is suppressed is challenging for clinicians. An experiment using a rodent model was performed with the aim of determining the efficacy of host modulation by increasing the systemic level of cholesterol sulfate (CS) using Irosustat in the context of the bone healing process around dental implants. Methods: In 16 ovariectomised female Sprague-Dawley rats, 2 implant fixtures were placed in the tibial bones (1 fixture on each side). At 1 week after surgery, the high-CS group (n=8) received Irosustat-mixed feed, while the control group (n=8) was fed conventionally. Block specimens were obtained at 5 weeks post-surgery for histologic analysis and the data were evaluated statistically (P<0.05). Results: Unlike the high-CS group, half of the specimens in the control group demonstrated severe bone resorption along with a periosteal reaction in the cortex. The mean percentages of bone-to-implant contact (21.5%) and bone density (28.1%) near the implant surface were significantly higher in the high-CS group than in the control group (P<0.05), as was the number of Haversian canals (by 5.3). Conclusions Host modulation by increasing the CS level may enhance the osseointegration of dental implants placed under conditions of impaired bone healing.

Background and Objectives: Various materials are used to perform post-mastoidectomy mastoid obliteration (MO) to reduce the risk of recurrent infections, stasis of secretions, or caloric dizziness. Autologous materials used as fillers for MO tend to be insufficient owing to shrinkage over time or inadequate volume of these substances. Synthetic materials are unsatisfactory for MO because of the risk of rejection and extrusion. We investigated the safety and effectiveness of bone allografts for post-mastoidectomy MO. Subjects and Methods: We reviewed the medical records of patients who underwent mastoidectomy with MO between January 2013 and January 2021. In the MO group, bone allografts were additionally used to fill the residual mastoid cavity. In the canal wall down (CWD) group, all patients underwent CWD mastoidectomy with use of additional inferiorly based mucoperiosteal flaps. Results: The study included the MO group (23 ears) and the CWD group (53 ears). In the MO group, compared with the preoperative status, we observed a decrease in the tendency of the air-bone gap postoperatively. Compared with the CWD group, the total complication rate showed a decreasing tendency in the MO group. Conclusions No patient showed post-MO shrinkage of the grafted bone allograft or otorrhea. Further large-scale studies are warranted to confirm the advantages of bone allografts for MO, including maintenance with time and sufficient amount.

Purpose: This study aims to report the efficacy and safety of one-snip punctoplasty and 18-gauge irrigation technique in patients with primary canaliculitis. Methods: All patients diagnosed with primary canaliculitis between January 2020 and August 2021 at Inje University Busan Paik Hospital are included. All patients underwent one-snip punctoplasty and 18-gauge irrigation technique. After the procedure, patients had topical antibiotics. The resolution of symptoms and inflammatory signs and complications were evaluated 3 weeks after the procedure. Results: A total of 11 patients (eight female patients and three male patients, 14 canaliculi) aged 34 to 82 years with a mean age of 63.8 ± 15.7 years were participated. Common symptoms were epiphora, mucopurulent discharge, and injection, and common signs were discharge from punctum, pouting punctum, punctal erythema, and swellling. Among 14 canaliculi, 12 (85.7%) had complete resolution and two underwent second treatment which showed completed resolution after the treatment. Conclusions One-snip punctoplasty and 18-gauge irrigation technique are minimally invasive to punctum and canaliculi and are a highly effective surgical procedure for patients with primary canaliculitis.

Purpose: This study aimed to compare the characteristics of venous thromboembolic disease (VTE) in Korean to Caucasian population. Materials and Methods: XALIA-LEA and XALIA were phase IV non-interventional prospective studies with identical designs that investigated the effect of rivaroxaban versus standard anticoagulation for VTE. Koreans accounted for the largest proportion of the overall enrolled population of XALIA-LEA. However, in the XALIA study, most patients were Caucasian. Therefore, Korean data from XALIA-LEA and Caucasian data from XALIA were used in this study. This study compared the clinical characteristics and primary outcomes of the XALIA program, including major bleeding, recurrent VTE, and all-cause mortality. Results: The Korean population was older, was less obese, and had more active cancer at baseline than the Caucasian population. Provoked VTE was more common in the Korean population. Interestingly, Koreans showed less accompanying thrombophilia than Caucasians, and factor V Leiden mutations were not detected. Korean analyses comparing the effects of rivaroxaban and standard anticoagulation with primary outcomes showed a lower incidence of major bleeding, recurrent VTE, and all-cause mortality with rivaroxaban. Similar results were obtained in the propensity score matching analysis. Conclusion Characteristic differences were found between Korean and Caucasian VTE patients. Despite these ethnic differences, the effectiveness and safety of rivaroxaban therapy in these patients were consistent.

Purpose: The aim of this study was to investigate the association between the changes in masticatory function and cognitive impairment by analyzing longitudinal data of older Korean patients. Materials and Methods: Patients aged over 60 years with dental records between 2005 to 2010 (baseline; T1) and 2014 to 2020 (follow-up; T2) were selected in a single medical center. Based on the dementia diagnosis after T2, the cohort was classified into two groups, the dementia group (n=122) and the control group (n=366). Changes in masticatory function were calculated using the total functional tooth unit (T-FTU) in both groups. The incidence of tooth extraction (%) and the subsequent rehabilitation during the observation period were also evaluated. Results: In the dementia group, T-FTU significantly decreased from T1 to T2 (9.81±2.78 to 9.11±3.16, respectively, p=0.008), while no significant change was observed in the control group. During the mean observation period of 9 years, significantly more teeth were extracted and neglected to be prosthetically restored in the dementia group than in the control group. Regression analysis revealed that the number of missing teeth neglected [odds ratio (OR)=1.195, 95% confidence interval (CI)=1.025–1.393, p=0.023] and previous alcohol consumption (OR=4.445, 95% CI=1.831–1.795, p=0.001) were the most significant risk factors of dementia. Conclusion There might be a causative relationship between the neglected missing dentition and the onset of dementia.

Background: Coronavirus disease 2019 (COVID-19) is generally asymptomatic or mild in otherwise healthy children, however, severe cases may occur. In this study, we report the clinical characteristics of children classified as critical COVID-19 in Korea to provide further insights into risk factors and management in children. Methods: This study was a retrospective case series of children < 18 years of age classified as critical COVID-19. Cases were identified by the Korea Disease Control and Prevention Agency surveillance system and medical records were reviewed. Critical COVID-19 was defined as cases with severe illness requiring noninvasive (high flow nasal cannula, continuous positive airway pressure, or bilevel positive airway pressure) or invasive mechanical ventilation, extracorporeal membrane oxygenation (ECMO) or continuous renal replacement therapy (CRRT), between January 20, 2020 and October 7, 2021. Results: Among 39,146 cases diagnosed with COVID-19 in subjects < 18 years of age, eight cases (0.02%) were identified as critical COVID-19. The median age was 13 years (range 10 month–17 years) and male-to-female ratio was 1:1. Three children had underlying diseases; one child has asthma and major depressive disorder, one child had LennoxGastaut syndrome and one child had mental retardation and was newly diagnosed with type 2 diabetes mellitus with the diagnosis of COVID-19. Among the eight children, seven were obese (body mass index range [BMI] median 29.3, range 25.9–38.2, weight-for-length > 97% for infant) and one was overweight (BMI 21.3). All patients had fever, six patients had dyspnea or cough and other accompanied symptoms included sore throat, headache, lethargy and myalgia. Radiologic findings showed pneumonia within 1–8 days after symptom onset. Pneumonia progressed in these children for 2–6 days and was improved within 5–32 days after diagnosis. Among the eight critical cases, remdesivir was administered in six cases.Steroids were provided for all cases. Inotropics were administered in one case. Six cases were treated with noninvasive mechanical ventilator and three required mechanical ventilator. One case required ECMO due to acute respiratory distress syndrome. All cases were admitted to the intensive care unit and admission period ranged from 9–39 days. Among all critical COVID-19 cases < 18 years of age, there were no fatal cases. Conclusion To develop appropriate policies for children in the COVID-19 pandemic, it is important to monitor and assess the clinical burden in this population.

Background: To evaluate the health status of healthcare workers (doctors and nurses) compared to those in the general population based on the National Health Insurance Service database and the cause of death data from Statistics Korea. Methods: The subjects of this study were 104,484 doctors and 220,310 nurses working in healthcare facilities from 2002 to 2017, and who had undergone at least one general medical examination. Based on the subject definition, the subject data were extracted from the National Health Insurance healthcare facility database and qualification database. We collected medical use details included in the research database, general medical examination results, medical history included in the health examination database, and additional data on the cause of death from the National Statistics database to analyze the main cause of death and mortality. Results: In terms of the major causes of death and mortality among healthcare workers, the mortality rate associated with intentional self-harm, injury, transportation accident, heart disease, addiction, and falling was significantly higher than that in the general population. Further, the prevalence of respiratory and gastrointestinal diseases was high. When analyzing the proportional mortality ratio (PMR) by cause of death for healthcare workers, the PMR values for death related to malignant neoplasm was the highest. In terms of diseases, both doctors and nurses had higher rates of infectious diseases such as maternal sepsis, rubella, and measles. Conclusion The health status of healthcare workers differs from that of the general population. Thus, it is important to consider the occupational characteristics of healthcare personnel. This study is unique in that it was conducted based on medical use indicators rather than survey data.

Background: Injury is a social problem that causes health and property losses, and it is important to identify the size and trend of injury for efficient prevention and management.Therefore, this study analyzed the trends in injury mortality and hospitalization rates from 2005 to 2019 in Korea. Methods: Using mortality data by Statistics Korea and Korea National Hospital Discharge In-depth injury survey by the Korea Disease Control and Prevention Agency (KDCA), age standardized rates were calculated for death and hospitalization to analyze trends and annual changes with the joinpoint regression model. In addition, annual changes in the hospitalization rate of the transport accident and fall injuries by age group were analyzed, which are the major causes of injuries. Results: From 2005 to 2019, the injury mortality rate has been on the decline, but the injury hospitalization rate has been on the rise. The annual rate of change varied depending on the injury mechanism, but the mortality rate tended to decrease or remain similar level, while the rate of hospitalization has steadily increased. In addition, by age group, injury mortality and hospitalization rates were high in the elderly. In particular, the hospitalization rate of the elderly was higher when comparing the hospitalization rate of the children in transport accidents and falls. Pedestrian transport accidents tended to decrease under the age of 15, but remained similar for those aged 65 and older, and bicycle accidents tended to increase in both groups. In addition, hospitalization rates were higher in the fall, with both groups showing a statistically significant increase in hospitalization rates caused by falls. Conclusion This study analyzed the trend of injury mortality and hospitalization and found that transport accidents and falls may vary depending on the means or age of the accident.Since injury is a big social problem that is a burden of disease, safety education and legal sanctions for injury prevention should be further improved in the future, especially by prioritizing vulnerable groups by age and detailed mechanisms of injury.

With the introduction of life-course epidemiology, researchers realized the importance of identifying risk factors in early life to prevent chronic diseases. This led to the establishment of the Ewha Birth and Growth Study in 2001; the study is a prospective birth cohort designed to provide evidence of early life risk factors for a child’s growth and health. Participants were recruited from those who visited Ewha Womans University Mokdong Hospital (a tertiary hospital in southwest Seoul, Korea) for prenatal care at 24-28 weeks of gestation. In total, 891 mothers enrolled in this study between 2001 and 2006 and their offspring (n=940) were followed-up. Regular check-up examinations of offspring were conducted at 3 years, 5 years, and 7 years of age and every year thereafter. To consider age-related health issues, extensive data were collected using questionnaires and measurements. In 2021, the study subjects will reach 19 years of age, and we are planning a check-up examination for early adulthood. About 20 years have passed since the cohort data were collected, and we have published results on childhood health outcomes associated with prenatal and birth characteristics, genetic and epigenetic characteristics related to childhood metabolism, the effects of exposure to endocrine disruptors, and dietary patterns in childhood. Recently, we started reporting on topics related to adolescent health. The findings will facilitate identification of early life risk factors for chronic diseases and the development of interventions for diseases later in life.

With the introduction of life-course epidemiology, researchers realized the importance of identifying risk factors in early life to prevent chronic diseases. This led to the establishment of the Ewha Birth and Growth Study in 2001; the study is a prospective birth cohort designed to provide evidence of early life risk factors for a child’s growth and health. Participants were recruited from those who visited Ewha Womans University Mokdong Hospital (a tertiary hospital in southwest Seoul, Korea) for prenatal care at 24-28 weeks of gestation. In total, 891 mothers enrolled in this study between 2001 and 2006 and their offspring (n=940) were followed-up. Regular check-up examinations of offspring were conducted at 3 years, 5 years, and 7 years of age and every year thereafter. To consider age-related health issues, extensive data were collected using questionnaires and measurements. In 2021, the study subjects will reach 19 years of age, and we are planning a check-up examination for early adulthood. About 20 years have passed since the cohort data were collected, and we have published results on childhood health outcomes associated with prenatal and birth characteristics, genetic and epigenetic characteristics related to childhood metabolism, the effects of exposure to endocrine disruptors, and dietary patterns in childhood. Recently, we started reporting on topics related to adolescent health. The findings will facilitate identification of early life risk factors for chronic diseases and the development of interventions for diseases later in life.