Detection of pit and fissure sealant microleakage using quantitative light-induced fluorescence technology: an in vitro study.

This in vitro study aimed to evaluate the feasibility of quantitative light-induced fluorescence (QLF) technology for detecting the presence and severity of microleakage of pit and fissure sealants. The areas of interest (AOIs) were 160 pits and fissures of 40 extracted permanent teeth. Fluorescent images were acquired using a QLF device, and the maximum fluorescence loss ΔFmax of each AOI was analyzed. After staining and cross-sectioning of the teeth, histological dye penetration was scored on a scale of 0 to 3. The relationship between ΔFmax and microleakage depth was analyzed, and the areas under the curve (AUCs) were calculated. The │ΔFmax│ increased as microleakage depth increased. The ΔFmax values of microleakage areas showed a strong significant correlation with the histological scores of dye penetration (r = - 0.72, P = 0.001). AUC analysis showed a high diagnostic accuracy for microleakage depth (AUC = 0.83-0.91). The highest AUC of 0.91 was found when differentiating the outer half microleakage of the sealant (histological score 0 vs. 1-3). QLF technology is effective in assessing the presence and severity of microleakage, suggesting its potential for noninvasive detection and monitoring of sealant microleakage in clinical settings.

Cost-consequence analysis of continuous denosumab therapy for osteoporosis treatment in South Korea.

BACKGROUND: Insurance reimbursement provisions in South Korea limit osteoporosis medication availability for patients with T-scores exceeding - 2.5. This study aimed to evaluate the financial impact and fracture prevention of continuous denosumab therapy until a T-score>-2.0 (Dmab-C strategy), versus discontinuation of denosumab after reaching T-score>-2.5 (Dmab-D strategy) in osteoporosis patients. METHODS: A cost-consequence analysis from a Korean healthcare system perspective was performed using a newly developed Markov model. The incidence of vertebral and non-vertebral fracture, fracture-related deaths, drug costs, and fracture-treatment costs were estimated and compared between Dmab-C and Dmab-D strategy over a lifetime in eligible patients aged 55 years. RESULTS: Base-case analysis revealed that Dmab-C prevented 32.21 vertebral fracture (VF) and 12.43 non-VF events per 100 patients over a lifetime, while reducing 1.29 fracture-related deaths. Lifetime direct healthcare cost saving per patient was KRW 1,354,655 if Dmab-C replaces Dmab-D. When productivity losses were considered, Dmab-C saved KRW 29,025,949 per patient compared to Dmab-D. The additional treatment costs of Dmab-C could be offset by the higher subsequent treatment costs and fracture treatment costs of Dmab-D. The sensitivity analysis showed consistent patterns with results of the base-case analysis. CONCLUSION: Continuous treatment using denosumab until osteoporosis patients achieve and maintain a T-score of -2.0 would provide greater clinical and economic benefits in terms of fracture prevention and reduced mortality risks compared to outcomes from discontinuing treatment at a T-score of -2.5 or above. This new treatment strategy would effectively lower the risk of fractures and fracture-related mortality, ultimately leading to lower medical expenses.

Knowledge Evaluation of Oral Diseases and Perception of Cooperation with Dental Experts for Oral Care of Nurses in Intensive Care Units in Korea: A Preliminary Study.

The aim of this study was to identify the status of education and knowledge concerning oral diseases for oral care as they relate to intensive care unit (ICU) nurses, as well as to investigate the perception of oral care education and practice, as led by dental experts. This study conducted a self-report survey consisting of 33 questions on education and knowledge about oral diseases, as well as perception of dental expert-led education and practice, targeting 240 nurses in the ICU. Finally, 227 questionnaires were analyzed, and 75.3% of the participants were staff nurses, and 41.4% were in the medical ICU. In the area of education and knowledge of major oral diseases, more than 50% of the respondents treating gingivitis, periodontitis, and dental caries did not complete dental education, and it was found that more than half of the respondents were unable to distinguish diseases of the mouth. It was recognized that more than half of nurses required dental expert-led education and practice. In this study, the education and knowledge of oral diseases of ICU nurses were found to be insufficient, and the need for the cooperation of dental experts was high. Therefore, collaboration to improve oral care practical guidelines for realistically applicable ICU patients will be needed.

The growth status of North Korean refugee adolescents in South Korea: comparison with South Korean adolescents.

AIM: To assess the growth status of North Korean refugee adolescents (NKRA) living in South Korea (SK) and compare their growth status with that of SK adolescents (SKA). SUBJECTS AND METHODS: NKRA were interviewed from 2017 to 2020, whereas the data for SKA were from the 2016 to 2018 Korea National Health and Nutrition Examination Surveys. SKA and NKRA were matched by age and gender in a 3:1 ratio and 534 SKA and 185 NKRA were enrolled. RESULTS: After adjusting for the covariates, NKRA had greater prevalences of thinness (odds ratio [OR], 11.5; 95% confidence interval [CI], 2.9-45.6) and obesity (OR, 12.0; 95% CI, 3.1-46.1) than SKA, but were not of short stature. In comparison with SKA in low-income families, NKRA had similarly greater prevalences of thinness and obesity, but not of short stature. As the length of stay of NKRA in SK increased, the prevalence of short stature and thinness did not decrease, while the prevalence of obesity increased significantly. CONCLUSION: Although they had lived in SK for several years, NKRA had greater prevalences of thinness and obesity than SKA and the prevalence of obesity increased significantly with the length of stay in SK.

Red fluorescence for assessing longitudinal tooth fractures.

BACKGROUND: This study was designed to determine whether autofluorescence emitted from longitudinal tooth fractures (LTFs) differs between fracture types, with the aim of determining which clinical factors are related to red fluorescence at the fracture line. METHODS: Thirty-three extracted teeth were classified into cracked teeth, split teeth, and root fractures using LTF types according to the American Association of Endodontists classification. The types of LTFs were identified using an operating microscope. LTF autofluorescence was captured using a fluorescence technique. Clinical examinations were performed using the preoperative factors from clinical and radiographic findings. RESULTS: Red fluorescence was identified in 82% and 83% of cracked and split teeth, respectively. None of the vertical root fractures exhibited red fluorescence (p<0.001). When red fluorescence was identified on the outer tooth surface, it penetrated into the crack line, but fluorescence that was not red at the tooth surface did not penetrate the fracture line. Among the examined preoperative clinical factors, differences between the presence and absence of red fluorescence were identified for sinus tract formation (p = 0.021), and radiographic features (p = 0.027). Regression analysis revealed a significant factor related to the red fluorescence, with sinus tract formation having a negative effect on red fluorescence (odds ratio [OR]=0.09). The presence of comprehensive periradicular lesions in radiography had a positive effect on red fluorescence (OR=5.04). CONCLUSIONS: Cracks originating from tooth crowns in certain types of LTFs were associated with red fluorescence, and cracks with red fluorescence were associated with extensive periodontal bone resorption around the teeth roots.

Prevalence and socioeconomic burden of diabetes mellitus in South Korean adults: a population-based study using administrative data.

BACKGROUND: Diabetes leads to severe complications and imposes health and financial burdens on the society. However, currently existing domestic public health studies of diabetes in South Korea mainly focus on prevalence, and data on the nationwide burden of diabetes in South Korea are lacking. The study aimed to estimate the prevalence and economic burden of diabetes imposed on the South Korean society. METHODS: A prevalence-based cost-of-illness study was conducted using the Korean national claims database. Adult diabetic patients were defined as those aged ≥20 years with claim records containing diagnostic codes for diabetes (E10-E14) during at least two outpatient visits or one hospitalization. Direct costs included medical costs for the diagnosis and treatment of diabetes and transportation costs. Indirect costs included productivity loss costs due to morbidity and premature death and caregivers' costs. Subgroup analyses were conducted according to the type of diabetes, age (< 65 vs. ≥65), diabetes medication, experience of hospitalization, and presence of diabetic complications or related comorbidities. RESULTS: A total of 4,472,133 patients were diagnosed with diabetes in Korea in 2017. The average annual prevalence of diabetes was estimated at 10.7%. The diabetes-related economic burden was USD 18,293 million, with an average per capita cost of USD 4090 in 2019. Medical costs accounted for the biggest portion of the total cost (69.5%), followed by productivity loss costs (17.9%), caregivers' costs (10.2%), and transportation costs (2.4%). According to subgroup analyses, type 2 diabetes, presence of diabetic complications or related comorbidities, diabetes medication, and hospitalization represented the biggest portion of the economic burden for diabetes. As the number of complications increased from one to three or more, the per capita cost increased from USD 3991 to USD 11,965. In inpatient settings, the per capita cost was ~ 10.8 times higher than that of outpatient settings. CONCLUSIONS: South Korea has a slightly high prevalence and economic burden of diabetes. These findings highlight the need for effective strategies to manage diabetic patients and suggest that policy makers allocate more health care resources to diabetes. This is the first study on this topic, conducted using a nationally representative claims database in South Korea.

Efficacy of a Nickel-Titanium Ultrasonic Instrument for Biofilm Removal in a Simulated Complex Root Canal.

This study evaluated the effectiveness of NiTi ultrasonic tips for Enterococcus faecalis (E. faecalis) biofilm removal in simulated complex root canals. Sixty root canal models consisting of a 30-degree curved main canal and two lateral canals were constructed from polydimethylsiloxane and incubated with E. faecalis. Irrigants in root canals were activated using a manual syringe (SI), a stainless steel (SS) instrument, a nickel-titanium (Ni-Ti) ultrasonic instrument, or a sonic instrument (EA). Instruments of SI, SS, and NiTi-9 groups were placed 9 mm from the apex, whereas those in NiTi-2 and EA groups were placed 2 mm from the apex. The efficacy of each method was determined as the ratio of fluorescence concentration before and after activation. In the apical curved canal, the highest efficacy was found in the NiTi-2 group (99.40%), followed by SI (84.25%), EA (80.38%), SS (76.93%), and NiTi-9 (67.29%) groups. In lateral canals 1 and 2, the efficacy was the highest in the NiTi-2 group and the lowest in the SI group. The NiTi ultrasonic instrument could effectively remove biofilms in the curved canal and lateral canals. This instrument should be introduced close to the working length. An up-and-down motion of the activation instrument is recommended.

Using autofluorescence to detect bacterial contamination in root fractures.

OBJECTIVES: Conventional methods for detecting root fractures cannot assess their depth or bacterial contamination. This study was designed to measure the autofluorescence emitted from a root fracture, with the aim of determining whether this is a suitable method for quantifying the depth and bacterial invasion of a fracture. METHODS: This in vitro study investigated 33 mandibular second molars with periapical lesions that had been extracted after finding root fractures in endodontically treated teeth during intentional replantation or diagnostic surgery. The root fractures were scanned using a fluorescence technique, and the association between fluorescence parameters and fracture depth was analyzed. The significance of the association between the red fluorescence among autofluorescence parameters and bacterial contamination within the fracture was examined. RESULTS: When the depth of the root fractures was evaluated by micro computed tomography, the scattering of light in the fractures increased with depth, and there was a gradual increase in the quantitative fluorescence parameter indicating the deepest point (ΔFmax) in the fractures. In addition, we observed red fluorescence on the outer surface of deeper fractures. The tooth fractures exhibiting red fluorescence were evaluated for bacterial contamination associated with red-fluorescent porphyrin, which revealed bacterial invasion into these fractures. On the other hand, non-red-fluorescing fractures contained necrotic tissue, debris, and irritants. CONCLUSIONS: This viable fluorescent technique can potentially quantify the depth of root fractures and be used as a risk indicator for root fractures with periodontal inflammation. CLINICAL SIGNIFICANCE: The auto-fluorescence technique can be used to detect depth and bacterial contamination of root fractures. It is postulated that the auto-fluorescence can be used as a risk indicator of deep fractures and can replace conventional fracture detection methods.

Estimation of Health Utilities Based on the Response to Treatment in Atopic Dermatitis: a Population-based Study.

PURPOSE: This study estimated utility weights based on the response to treatment for atopic dermatitis in the general population. METHODS: The Korean general population aged 20-60 years was stratified by using a random sampling method based on age and sex. Two hypothetical health states of atopic dermatitis were developed: response to treatment and no response to treatment. Health utility values were estimated by using time trade-off (TTO) based on a period of 10 years, TTO based on life expectancy, and EuroQol 5-Dimension (EQ-5D) including a visual analog scale (VAS). The mean utility value and 95% CI were derived, and comparisons of subgroups using the t test and ANOVA were performed. We conducted a multilevel analysis after controlling the sociodemographic variables to consider repeated measures. FINDINGS: A total of 155 participants were included in the survey. Their mean age was 39.7 years; 58.7% of participants were women. The mean health utility values for response and no response using TTO based on 10 years were 0.847 and 0.380, respectively. The estimated health utility values of response and no response were 0.865 and 0.476 using TTO based on life expectancy, and 0.814 and 0.279 using EQ-5D. For VAS, the response and no response were 0.744 and 0.322. After controlling the covariates, the important factors that affected utility values were response and no response to treatment (P < 0.001). IMPLICATIONS: This study showed that the utility weights of people with no response to atopic dermatitis treatment were lower compared with response from the general population. Health care providers should therefore consider symptom control as an important factor affecting the quality of life of those with atopic dermatitis.

Healthcare Costs for Acute Hospitalized and Chronic Heart Failure in South Korea: A Multi-Center Retrospective Cohort Study.

PURPOSE: Although heart failure (HF) is recognized as a leading contributor to healthcare costs and a significant economic burden worldwide, studies of HF-related costs in South Korea are limited. This study aimed to estimate HF-related costs per Korean patient per year and per visit. MATERIALS AND METHODS: This retrospective cohort study analyzed data obtained from six hospitals in South Korea. Patients with HF who experienced ≥one hospitalization or ≥two outpatient visits between January 1, 2013 and December 31, 2013 were included. Patients were followed up for 1 year [in Korean won (KRW)]. RESULTS: Among a total of 500 patients (mean age, 66.1 years; male sex, 54.4%), the mean 1-year HF-related cost per patient was KRW 2,607,173, which included both, outpatient care (KRW 952,863) and inpatient care (KRW 1,654,309). During the post-index period, 22.2% of patients had at least one hospitalization, and their 1-year costs per patient (KRW 8,530,290) were higher than those of patients who had only visited a hospital over a 12-month period (77.8%; KRW 917,029). Among 111 hospitalized patients, the 1-year costs were 1.7-fold greater in patients (n=52) who were admitted to the hospital via the emergency department (ED) than in those (n=59) who were not (KRW 11,040,453 vs. KRW 6,317,942; p<0.001). CONCLUSION: The majority of healthcare costs for HF patients in South Korea was related to hospitalization, especially admissions via the ED. Appropriate treatment strategies including modification of risk factors to prevent or decrease hospitalization are needed to reduce the economic burden on HF patients.

Explaining the Red Fluorescence Evident on the Surface of Failed Dental Implants: Case Reports.

INTRODUCTION: It is important to identify the reasons for implant failure when planning future dental treatment. No studies have distinguished the factors that affect implant failure by evaluating the appearance of failed fixtures. PURPOSE: This study investigated these factors by evaluating the surface of implant fixtures using quantitative light-induced fluorescence-digital (QLF-D), which involves detecting the red fluorescence emitted by porphyrin metabolized by oral bacteria in a mature biofilm. MATERIALS AND METHODS: The areas of red fluorescence in QLF-D images obtained from all aspects of the fixture surface were then analyzed using quantitative analysis software. RESULTS: Red fluorescence was evident on the surface of implants that failed after at least 2 years of occlusal loading and exhibited severe bone loss. Implants with no fluorescence exhibited a clean surface in blue-light images, and the bone loss could not be observed radiographically. CONCLUSIONS: The cases presented that failed dental implant surfaces caused by periimplantitis can be detected by the red fluorescence evident as QLF-D.

Higher prevalence of dementia in patients with schizophrenia: A nationwide population-based study.

INTRODUCTION: This study investigates the prevalence of dementia in patients with and without schizophrenia, with a particular focus on age-specific and sex-specific differences. METHODS: We conducted a population-based study using the National Health Insurance claims database from 2010 to 2013. Using a 10:1 matching ratio, 248,919 patients without schizophrenia and 26,591 patients with schizophrenia were identified based on the ICD-10 code. Patients with dementia were extracted by diagnosis or use of anti-dementia drugs. Conditional logistic regression analyses were performed to evaluate the association between schizophrenia and dementia. RESULTS: The prevalence of dementia was significantly higher in schizophrenia patients compared with that in matched non-schizophrenia patients (9.9% versus 2.2%, P < 0.0001). After adjusting for Charlson comorbidity index and underlying comorbidities, conditional logistic regression showed that schizophrenia was associated with dementia (adjusted odds ratio [AOR], 4.7; 95% confidence interval [CI], 4.4-5.1). When stratified by sex, the AOR was 5.6 (95% CI, 5.0-6.2) among women and 4.0 (95% CI, 3.6-4.5) among men. Moreover, the association between dementia and schizophrenia was strong in elderly patients. The AOR of dementia prevalence was 6.6 (95% CI, 6.1-7.2) in patients aged ≥65 years and 3.4 (95% CI, 3.0-3.8) in patients aged <65 years. DISCUSSION: Schizophrenia patients were more likely to have dementia compared with non-schizophrenia patients. This association seems greater in higher prevalence groups such as women and patients aged ≥65 years. Further investigation on the mechanism is required.

Cost-effectiveness of Bedaquiline for the Treatment of Multidrug-resistant Tuberculosis in the Republic of Korea.

PURPOSE: Bedaquiline is a new drug used for the treatment of multidrug-resistant tuberculosis (MDR-TB). This study aimed to evaluate the cost-effectiveness of adding bedaquiline to a standard regimen (SR) for treating patients with MDR-TB, including extensively drug-resistant (XDR)-TB, in the Republic of Korea. METHODS: A cohort-based decision-analytic model developed in a previously published study from the United Kingdom was used, with a 20-year time horizon and a 5% discount rate for cost and effectiveness, to evaluate the incremental cost-effectiveness ratios of bedaquiline + SR and SR only. The key parameters regarding the clinical data were available via the published Phase II trial of bedaquiline. Additional parameters for recurrence, cure status, loss to follow-up, surgery, death, cost, and health utility were based on Korean data if available; otherwise the international literature data were applied. Univariate and probabilistic sensitivity analyses were conducted. FINDINGS: Based on the analysis, a patient on bedaquiline + SR would gain 1.20 quality-adjusted life-years (QALYs) at 13,961,659 Korean won (KRW) (1100 KRW = US $1) of additional cost compared with a patient administered SR only, with an incremental cost/utility ratio of 11,638,656 KRW/QALY. Bedaquiline + SR had an 80% probability of being cost-effective, at a willingness-to-pay threshold of 26 million KRW, compared with SR only. IMPLICATIONS: The results of this study suggest that, in the Republic of Korea, bedaquiline, as a part of combination therapy with SR, is a cost-effective option for the treatment of MDR-TB (including XDR-TB) compared with SR only.

Detection and Analysis of Enamel Cracks by Quantitative Light-induced Fluorescence Technology.

INTRODUCTION: The ability to accurately detect tooth cracks and quantify their depth would allow the prediction of crack progression and treatment success. The aim of this in vitro study was to determine the capabilities of quantitative light-induced fluorescence (QLF) technology in the detection of enamel cracks. METHODS: Ninety-six extracted human teeth were selected for examining naturally existing or suspected cracked teeth surfaces using a photocuring unit. QLF performed with a digital camera (QLF-D) images were used to assess the ability to detect enamel cracks based on the maximum fluorescence loss value (ΔFmax, %), which was then analyzed using the QLF-D software. A histologic evaluation was then performed in which the samples were sectioned and observed with the aid of a polarized light microscope. The relationship between ΔFmax and the histology findings was assessed based on the Spearman rank correlation. The sensitivity and specificity were calculated to evaluate the validity of using QLF-D to analyze enamel inner-half cracks and cracks extending to the dentin-enamel junction. RESULTS: There was a strong correlation between the results of histologic evaluations of enamel cracks and the ΔFmax value, with a correlation coefficient of 0.84. The diagnostic accuracy of QLF-D had a sensitivity of 0.87 and a specificity of 0.98 for enamel inner-half cracks and a sensitivity of 0.90 and a specificity of 1.0 for cracks extending to the dentin-enamel junction. CONCLUSIONS: These results indicate that QLF technology would be a useful clinical tool for diagnosing enamel cracks, especially given that this is a nondestructive method.

Use of injectable drugs with oral-formulation alternatives for outpatients in South Korea.

This study analyzed the use of injectable drugs with oral-formulation alternatives in the outpatient setting in South Korea. We conducted a retrospective cross-sectional data analysis using 2008 National Health Insurance claims data. All active ingredients were categorized into dual-formulation ingredients (DFIs) and single formulation ingredients (SFIs), and were identified by the type of healthcare service provider (HSP) and anatomical therapeutic chemical (ATC) group. 14.6 % (102/701) of total drugs were extracted as DFIs at about the same rate as that for drugs in the World Health Organization database (14.45 %), showing similar patterns by ATC group. The rate of injectable drug use varied more substantially for DFIs (range 0.94-4.54 %) than for SFIs (range 0.27-1.12 %) by the type of HSP. For DFIs, the highest proportion of injectable drug use was observed in group H (all hormonal preparations, 22.74 %) and group M (anti-inflammatory and anti-rheumatic preparations, 10.23 %) among ATC groups. The proportion of injectable drug use was higher in clinics and small hospitals than in tertiary hospitals and general hospitals where patients with more severe cases tend to visit. The results imply the potentially inappropriate or excessive use of injectable drugs and suggest the need to develop standard guidelines for injectable drug use and strategies to promote high-quality healthcare including education on rational prescribing.

Socioeconomic and employment status of patients with rheumatoid arthritis in Korea.

OBJECTIVES: This study investigates the prevalence of rheumatoid arthritis (RA) by gender and socio-economic characteristics. It also explores the differences in the employment status between RA patients and the general population without RA in Korea. METHODS: We analyzed data from the Fourth Korea National Health and Nutrition Examination Survey (KNHANES IV) conducted from 2007 to 2009. Prevalence rates were estimated for female and male patients with RA in terms of age, residence, education, income level, and occupation type. The female respondents aged 45 to 64 were divided into the RA population and the non-RA population in order to compare the employment status between the two groups. RESULTS: The annual physician-diagnosed RA prevalence rate was 1.45%. The prevalence rate was 2.27% for women and 0.62% for men. Individuals with RA had a significantly lower employment rate than individuals without RA (41.7 vs. 68.1%). The main reason for non-employment among RA patients was health-related problems (47.1%). There was statistically significant difference in employment type among the two groups. The experience rates for sick leave and sick-in-bed due to RA were 1.7 and 3.9%, respectively. CONCLUSION: Middle- and old-aged women accounted for the majority of the Korean RA population, which had a significant lower employment rate compared to the population without RA for both sexes. RA resulted in considerable productivity loss in Korea.