Neural cell adhesion molecule 1 is a cellular target engaged plasma biomarker in demyelinating Charcot-Marie-Tooth disease.

BACKGROUND AND PURPOSE: Elevated plasma concentrations of neural cell adhesion molecule 1 (NCAM1) and p75 neurotrophin receptor (p75) in patients with peripheral neuropathy have been reported. This study aimed to determine the specificity of plasma concentration elevation of either NCAM1 or p75 in a subtype of Charcot-Marie-Tooth disease (CMT) and its correlation with pathologic nerve status and disease severity. METHODS: Blood samples were collected from 138 patients with inherited peripheral neuropathy and 51 healthy controls. Disease severity was measured using Charcot-Marie-Tooth Neuropathy Score version 2 (CMTNSv2), and plasma concentrations of NCAM1 and p75 were analyzed by enzyme-linked immunosorbent assay. Eight sural nerves from CMT patients were examined to determine the relation of histopathology and plasma NCAM1 levels. RESULTS: Plasma concentration of NCAM1, but not p75, was specifically increased in demyelinating subtypes of CMT (median = 7100 pg/mL, p < 0.001), including CMT1A, but not in axonal subtype (5964 pg/mL, p > 0.05), compared to the control (3859 pg/mL). CMT1A patients with mild or moderate severity (CMTNSv2 < 20) showed higher levels of plasma NCAM1 than healthy controls. Immunofluorescent NCAM1 staining for the sural nerves of CMT patients showed that NCAM1-positive onion bulb cells and possible demyelinating Schwann cells might be associated with the specific increase of plasma NCAM1 in demyelinating CMT. CONCLUSIONS: The plasma NCAM1 levels in demyelinating CMT might be a surrogate biomarker reflecting pathological Schwann cell status and disease progression.

Did Dental Insurance Expansion Improve Dental Care Needs Among Korean Adults? Difference in Difference Analysis.

BACKGROUND: In 2012, the Korean government expanded dental insurance for the elderly to promote improved access to dental care. We examined the causal effect of this policy on dental care needs, focusing on low-income older adults. METHODS: We compared data before and after policy implementation using double difference (DD) and triple difference (DDD) analyses. We used the nationally representative data from the Korea National Health and Nutrition Examination Survey from 2010 and 2016-2018. Individuals aged ≥65 years were included in the treatment group, and individuals aged <65 years were included in the control group. RESULTS: Dental insurance expansion was associated with a paradoxical increase in perceived unmet dental needs among elderly individuals (8.8 percentage points increase, 95% CI: 4.7 to 13.0). However, there were improvements in dental prosthetics outcomes (denture wearing [4.0 percentage points, 95% CI: 0.2 to 7.9] and dental implants [5.0 percentage points, 95% CI: 2.1 to 7.9]; P < 0.01). Upon analyzing low-income elderly individuals using DDD analysis, we found that the insurance expansion led to a 21.6% smaller increase in unmet dental needs among low-income adults, compared to high-income adults (95% CI, -35.0 to -8.5; P < 0.01). CONCLUSION: Dental insurance expansion in South Korea resulted in improvements in access to dental prosthetic services overall. It also led to a smaller increase in unmet dental needs among low-income older adults, compared to high-income adults.

Factors predicting different times for brushing teeth during the day: multilevel analyses.

BACKGROUND: The most effective and simple intervention for preventing oral disease is toothbrushing. However, there is substantial variation in the timing of brushing teeth during the day. We aimed to identify a comprehensive set of predictors of toothbrushing after lunch and after dinner and estimated contextual (i.e., geographic) variation in brushing behavior at different times of the day. METHODS: We constructed a conceptual framework for toothbrushing by reviewing health behavior models. The main data source was the 2017 Community Health Survey. We performed a four-level random intercept logistic regression to predict toothbrushing behavior. (individual, household, Gi/Gun/Gu, and Si/Do). RESULTS: Individuals under 30 years of age had higher likelihood of brushing after lunch, while brushing after dinner was higher among those aged 40-79 years. People engaged in service/sales, agriculture/fishing/labor/mechanics, as well as student/housewife/unemployed were 0.60, 0.41, and 0.49 times less likely to brush their teeth after lunch, respectively, compared to those working in the office, but the gap narrowed to 0.97, 0.96, 0.94 for brushing after dinner. We also found significant area-level variations in the timing of brushing. CONCLUSIONS: Different patterns in association with various factors at individual-, household- and Si/Gun/Gu-levels with toothbrushing after lunch versus toothbrushing after dinner suggests a need for tailored interventions to improve toothbrushing behavior depending on the time of day.

Influence of job autonomy on job crafting of dental hygienists.

OBJECTIVES: Job autonomy focuses on the job performance and tasks of health providers with a national licence in South Korea, which affects job crafting, to develop job competency. This study was conducted to identify the influence of job autonomy on job crafting of dental hygienists. METHODS: This cross-sectional study included 411 dental hygienists extracted through convenience sampling from a pool of 35,000 clinical dental hygienists in South Korea. Measuring tool are Korean version of the Job Crafting Questionnaire (JCQ-K) and job autonomy questionnaire (JAQ). To investigate the level of job autonomy and crafting of dental hygienists based on their general characteristics, t-tests and one-way ANOVAs were performed. Pearson correlation was performed to determine the linear correlation between autonomy and crafting. To determine whether job autonomy affects job crafting, an adjusted regression analysis was conducted using general characteristics as control variables. RESULTS: High job autonomy and job crafting were associated with increases in participant age with job experience as a senior staff, education level, and work environment, such as dental office or hospital. A significant positive correlation was observed (r = 0.64) between job autonomy and job crafting. Job autonomy (ß = 0.58) and dental/medical hospital in university (ß = 0.13) had a significant relationship with dental hygienists' job crafting. CONCLUSIONS: Job autonomy could positively influence the job crafting of dental hygienists in South Korea. Our findings suggest that job latitude should be redesigned to promote task competency and social responsibility with a health outcome perspective for the population as well as the dental hygiene profession.

Did Expanded Dental Insurance Improve Chewing Ability in the Older Korean Population? Results of an Interrupted Time-series Analysis.

BACKGROUND: In 2012, the Korean National Health Insurance extended its coverage to include denture services for older adults. We examined whether the new policy resulted in improved chewing ability in the eligible population. METHODS: We used interrupted time-series (ITS) analysis, a quasi-experimental design, to analyze the effect of the policy. We used data from the Korea National Health and Nutrition Examination Survey conducted from 2007 to 2016-2018. The study population consisted of two groups: the treatment group, aged 65 years or older and eligible for the dental insurance benefit; and the control group, those younger than 65 years and ineligible. The main evaluated outcome was self-reported chewing difficulty. RESULTS: The ITS analysis showed that chewing difficulty decreased annually by 0.93% (95% CI, -1.30 to -0.55%) and 0.38% (95% CI, -0.59 to -0.16%) after the policy extension in the older than 65 and younger than 65 groups, respectively. However, we could not conclude that the insurance extension affected chewing difficulty because there was a decrease in the control group as well. CONCLUSION: Chewing ability improved in both older and younger adults regardless of dental insurance coverage for older adults. Other exogenous factors probably led to the improvements in chewing ability as well as dental insurance benefits.

Did the Expansion of Insurance Coverage for Oral Health Reduce Self-reported Oral Health Inequalities in Korea? Results of Repeated Cross-Sectional Analysis, 2007-2015.

BACKGROUND: In 2009, the South Korean government expanded universal health insurance to include oral health services. In the present study, we sought to examine whether improved access resulted in a reduction in income-based self-reported oral health inequalities. METHODS: We analyzed repeated cross-sectional data from the Korea National Health and Nutrition Examination Survey (KNHANES) waves IV through VI (2007-2015). We analyzed self-reported oral health status among 68,431 subjects. Changes in oral health inequalities across four income levels (low, middle-low, middle-high, and high) were assessed with the Slope Index of Inequality (SII) and the Relative Index of Inequality (RII). RESULTS: The average oral health status of children and adolescents improved the most over the observation period. The absolute magnitude of oral health inequalities (measured by the SII) improved for most groups, with the notable exception of young male adults. By contrast, the ratio of poor oral health between high- and low-income groups (measured by the RII) changed little over time, indicating that relative inequalities remained resistant to change. CONCLUSIONS: The expansion of dental health insurance may not be sufficient to move the needle on self-reported oral health inequalities among adults.

Development of an Oral and Maxillofacial Frailty Index: A preliminary study.

OBJECTIVE: The purpose of this study is to develop an index to measure oral and maxillofacial frailty in older adults as an acceptable screening tool. METHODS: Three hundred adults (aged ≥ 50 years) participated in this study by telephone interview. Ten candidate items for the Oral and Maxillofacial Frailty Index (OMFI) and 20 matched detailed items for oral and maxillofacial functions were asked. Information about sociodemographic and oral health-related variables was also obtained. The test-retest reliability of the 10 candidate items was determined. Correlations of the 10 candidate items with the 20 detailed items or sociodemographic and oral health-related variables were analysed to test the validity of the candidate items. To suggest optimal items for the OMFI, five different models with different numbers of items were constructed and evaluated based on their associations with main variables. RESULTS: The overall internal consistency of the 10 candidate items was .704, and the Cronbach's alpha value of each item was .23-.55. The test-retest reliability was excellent. There were significant correlations between the 10 candidate and 20 matched detailed items. The score of the 10 candidate items was significantly different according to gender, education level and oral health-related variables. The final five items for the OMFI were difficulties in chewing, the necessity of water when eating dry food, difficulties in jaw or tongue movements, difficulties in speaking or pronunciation and difficulties in facial expression. CONCLUSIONS: The five items could be used as a screening tool for evaluating oral and maxillofacial frailty in older adults.

Did expansion of insurance coverage for major diseases in Korea induce a positive spillover effect on dental service utilization?

Although people with serious major diseases are disproportionately likely to have poor oral health, they are also more likely to defer treatment for oral health conditions due to financial constraints. The South Korean government introduced a comprehensive benefit expansion policy covering four major disease categories in 2013: cancer, cardiac diseases, cerebrovascular diseases, and rare diseases. Meanwhile, a policy expanding benefits for dental prosthetic services for the elderly was also introduced during the same period. Using nationally representative Korean Health Panel data from 2012 to 2017, we performed a difference-in-difference (DID) analysis to examine the positive spillover effect of insurance expansion for the four major disease categories on encouraging dental service utilization (frequency of dental visits and dental out-of-pocket payments) or decreasing unmet dental needs. Additionally, a triple-difference (TD) analysis was performed to examine whether the effect of coverage expansion of dental prosthetic services on dental service utilization was larger among the beneficiaries of the expansion for the four major disease categories. Benefit expansion for the four major disease categories did not significantly affect dental service utilization among the beneficiaries (DID model) during all study years and slightly increased unmet dental needs in 2014 and 2015. However, the effect of expanded coverage for dental prosthetic services on encouraging dental service utilization was larger (TD model) among the beneficiaries of the policy for the four major disease categories than among non-beneficiaries when we defined the beneficiaries as individuals with two or more household members who had one of the four major diseases. Our results suggest a need to provide more intense coverage for those with comorbidities by embracing the concept of proportionate universalism in the coverage of dental services.

Insurance coverage expansion and inequalities in unmet oral healthcare needs in Korea: Repeated cross-sectional analysis, 2007-2015.

OBJECTIVES: This study aimed to evaluate whether Korea's 2012 health insurance expansion of adult dental care coverage reduced income-based oral health inequalities. METHODS: This study analysed nationally representative repeated cross-sectional data from waves IV to VI (2007-2015) of the Korean National Health and Nutrition Examination Survey. The main outcome variable is unmet dental needs due to cost, and the independent variable is household income. Further, the slope index of inequality (SII) and the relative index of inequality (RII) were calculated. Calculations were adjusted for income and stratified by age group, gender and survey period. Data from the three waves were pooled to estimate the SII and RII trend coefficients between survey years. These were tested using two-way interaction terms for each age group and gender. RESULTS: Some changes in income-based inequality trends were identified. Relative and absolute inequalities in unmet needs (indicated by the RII and SII) decreased over time for most age groups. However, this trend was not observed for older women. CONCLUSIONS: Income-based inequalities in unmet dental needs persisted among older women in Korea despite the insurance expansion. By contrast, after the 2012 insurance expansion, the absolute and relative inequality in unmet dental needs decreased for young and middle-aged as well as older adults.

Did Expanded Dental Insurance Reduce Out-of-Pocket Expenditures on Dental Care among Older Adults in Korea? Interrupted Time-Series Analysis.

The Korean National Health Insurance extended its coverage to reduce the economic burden of receiving dentures and implants for older adults in 2012 and 2014, respectively. We examined whether the new policy resulted in reduced out-of-pocket dental care expenditure in the eligible population, specifically focusing on low-income adults. We used interrupted time-series analysis (ITSA), a quasi-experimental design, to identify the effects of the policy among persons aged 65 or older. Data were extracted from the Korea Health Panel Survey (KHP; 2008-2017). The main outcome was out-of-pocket expenditures on dental care. The ITSA showed that expenditures decreased annually by 4.5% (RR: 0.96, 95% CI: 0.95-0.96) between 2012 and 2014. However, expenditure increased by 7.8% (RR: 1.08, 95% CI: 1.07-1.08) after 2014. Dental insurance coverage did not contribute to reducing the out-of-pocket expenses for dentures among low-income adults, while coverage of dental implants led to an increase in dental expenditure.

Trends in Self-Rated Poor Oral Health Among all Age Populations in Korea from 2007 to 2015: Monitoring Expansion of Dental Insurance.

OBJECTIVES: This study explored trends in self-rated poor oral health (SRPOH) from 2007 to 2015 among all age groups to monitor changes after the expansion of dental insurance. METHODS: Repeated cross-sectional data from 2007 to 2015 Korea National Health and Nutrition Examination Surveys were collected and analysed. The respondents (n = 20,199) were categorised into four age groups: 0-19, 20-44, 45-64, and ≥65 years. The outcome variable was SRPOH, with independent variables being socioeconomic factors, sex, household income, and education. The age-sex standardised prevalence rate was calculated to determine trends, and complex samples logistic regression analysis was performed to confirm the factors affecting SRPOH. RESULTS: Self-rated poor oral health prevalence decreased significantly from 2007 to 2009 (25%) to 2013 to 2015 (14%) in the age groups of 0-19 and 20-44 years (P < 0.05), whereas the SRPOH prevalence in the age groups of 45-64 and ≥65 years did not undergo any significant changes. Although the prevalence decreased by 6% among older adults, over 40% older women still experienced SRPOH. A sex gap increased with age but did not change over time. SRPOH was strongly associated with sex, income, and education across all age groups; the association did not notably change from 2007 to 2015. CONCLUSIONS: Self-rated poor oral health improved among younger people in Korea. The gender gap in the prevalence increased with age and persisted over time. However, income was the strongest determinant of SRPOH among all age groups, regardless of dental insurance expansion. Further studies should aim to draw causal inferences to explore the policy impact of dental insurance benefits.

Impact of Long Working Hours and Shift Work on Perceived Unmet Dental Need: A Panel Study.

This study investigates whether workers with long working hours as well as shift workers perceive higher unmet dental care needs, and whether there is a gender difference in the associations. We used the Korea Health Panel (2009, 2011-2014) involving 20,451 person-wave observations from 5567 individuals. Perceived unmet dental care needs was defined when the participants reported that they perceived a need for dental treatment or check-up but had failed to receive dental care services during the past year. Fixed effects logit models were applied to examine how changes in weekly working hours or shift work status were linked to changes in perceived unmet dental needs within each individual. Among participants, 15.9-24.7% reported perceived unmet dental needs and the most common reason was time scarcity. We found that long working hours (>52 h/week) was significantly associated with perceived unmet dental needs due to time scarcity in both men (OR = 1.42, 95% CI 1.13-1.78) and women (OR = 1.35, 95% CI 1.03-1.79) compared workers working 40-52 h per week. Shift work was also a significant risk factor, but only in women (OR = 1.57, 95% CI 1.06-2.32). These findings provide evidence for labor policies to reduce working hours in order to improve access to dental care services.

Did expanded access to denture services improve chewing ability in the Korean older population? Results of a regression discontinuity analysis.

The Korean National Health Insurance expanded the dental insurance in 2012 to cover denture services for older adults. We analyzed whether the new policy improved of chewing ability in the eligible population. We used regression discontinuity (RD), a quasi-experimental design, to analyze the effects of the expanded dental insurance. We analyzed data from the Korea National Health and Nutrition Examination Survey conducted in 2010 and 2015. The study population consisted of two groups: the treatment group, aged 65 and above who were eligible; and the control group, under 65 years of age who were not eligible for the dental insurance benefit. The main outcome evaluated was self-reported chewing difficulty. The RD analysis showed that in 2015, the chewing difficulty in aged above 65 was 2.2% lower than in those aged under 65. However, the difference was not statistically significant (P = 0.76). The results from the falsification testing of predetermined covariates, placebo cut-offs, and bandwidths validated our main conclusion. The expansion of dental insurance benefits to include dentures for the older adults did not improve the chewing ability in the eligible population. Future studies should evaluate long-term outcomes of oral health as well as the social impacts on the elderly.

Dental hygienist job autonomy depends on the period of dental hygiene education.

CONTEXT: Independent dental hygiene practice is critical in regions with low accessibility to dental services, as well as for preventing and managing oral diseases among children and the elderly from low-income families, as these individuals are highly vulnerable to oral diseases. AIMS: We investigated whether the job autonomy of dental hygienists has been maintained, in accordance with the guidelines of the International Federation of Dental Hygienists (IFDH). SETTINGS AND DESIGN: This study comprised a cross-sectional literature review. SUBJECTS AND METHODS: We reviewed national reports and articles published in 23 countries selected for analysis to determine the degree of dental hygienist job autonomy, based on the extent of dental hygiene education. We divided the countries into two groups, based on the historical length of dental hygienist education. STATISTICAL ANALYSIS USED: We classified education as direct access, indirect supervision, and direct supervision. Two researchers reviewed and revised the classification results to ensure reliability. The Kappa value was 0.96 points. Statistical analysis was performed by PASW statistics 23.0 program (SPSS Inc., Chicago, IL, USA.). RESULTS: Countries with >40 years of educating dental hygienists exhibited more independent dental hygienist practices than those with less than 40 years of educating dental hygienists. CONCLUSIONS: Countries with >40 years of experience in educating dental hygienists largely guarantee independent dental hygiene practice for dental hygienists, in accordance with IFDH guidelines. The society's need for dental hygienists is fulfilled and professional competency is maintained in these contexts; thus, it should be required for dental hygienists to maintain independent dental hygiene practices.

Influence of dental insurance coverage on access to preventive periodontal care in middle-aged and elderly populations: analysis of representative Korean Community Health Survey Data (2011-2015).

OBJECTIVES: This study aimed to explore the influence of dental insurance coverage on access to preventive periodontal care. Data were extracted from the 2011, 2013 and 2015 Korean Community Health Surveys conducted by the Korea Centers for Disease Control and Prevention. MATERIALS AND METHODS: This study was designed as a 5-year time series analysis using secondary data. Trends in the utilisation rate of dental scaling services before and after the introduction of insurance coverage for dental scaling were evaluated, and the influence of dental insurance coverage on access to preventive periodontal care was assessed. RESULTS: In the 4 years after 2011, the utilisation rate of scaling services increased by 12.3%. The increase in the utilisation rate from 2011 to 2015 was greater for participants ≥ 65 years old and 45-64 years old compared with those who were 19-34 or 35-44 years old. The odds ratios (ORs) for using scaling in 2011, 2013 and 2015 were 0.9, 1.1 and 1.5, respectively, for participants with healthy gingiva. For elderly participants with gingival bleeding, the utilisation rate of scaling services increased after 2015 with ORs of 0.8, 0.9 and 1.2 for 2011, 2013 and 2015, respectively. CONCLUSIONS: Insurance coverage for dental scaling positively influenced access to preventive care for periodontal disease in middle-aged and elderly individuals. In the future, the long-term contributions of dental insurance coverage to the prevalence of periodontal disease and oral health disparities should be evaluated.

Regular dental scaling associated with decreased tooth loss in the middle-aged and elderly in Korea: A 3-year prospective longitudinal study.

CONTEXT: Tooth loss exacerbates the deterioration of physical function and induces illness. Numerous studies have identified the risk factors for tooth loss, and several have identified an association of tooth loss with sociodemographic factors, general health status, and lifestyle. AIMS: The objective of the present cohort study was to elucidate the relationship between regular dental scaling and tooth loss in middle-aged and elderly individuals in Korea. SETTINGS AND DESIGN: The study was 3-year prospective longitudinal study and conducted in Wonju-si of South Korea. METHODS: In total, 557 subjects (219 men, 338 women; 40-75 years) were included in our 3-year follow-up survey (2010-2014). Data from the Korean Genome and Epidemiology Study on Atherosclerosis Risk of Rural Areas in the Korean General Population (KOGES-ARIRANG) were used. All subjects underwent an oral examination and face-to-face interview for taking oral health behavior, sociodemographic status, and the utilization of dental service. STATISTICAL ANALYSIS USED: Logistic regression analysis was used to determine the effects of regular dental scaling on tooth loss after adjusting for history of oral examinations and dental visits, oral health behavior, and sociodemographic status. RESULTS: In total, 263 subjects (47.2%) experienced a loss of one or more teeth during the 3-year period, and lost a mean of 1.54 ± 2.53 teeth. The incidence of tooth loss was 1.87 (1.03-3.38) times higher in participants who did not undergo dental scaling during the 3-year period than in those who regularly received dental scaling. CONCLUSIONS: This study showed the potential causal relationship between tooth loss and regular dental scaling for preventing oral disease. Further study is needed to consolidate the evidence that regular dental scaling is effective in preventing tooth loss.

Estimating tooth retention by the number of present teeth in a middle-old-aged population: 3-year follow-up study in Korea.

BACKGROUND: The number of individual teeth decreases with age, resulting in a decrease in masticatory capacity, and is an important indicator of oral health. However, it is difficult to estimate the number of present teeth on the basis of age alone. OBJECTIVES: We aimed to determine whether tooth retention could be estimated by the number of present teeth in middle-old-aged individuals. MATERIAL AND METHODS: We used data from the Korean Genome and Epidemiology Study on Atherosclerosis Risk of Rural Areas in the Korean General Population (KoGES-ARIRANG). Subjects (40-75 years old) were invited to participate in a 3-year prospective follow-up survey conducted from 2010 to 2014. A total of 557 individuals (219 men and 338 women) took part in the study. Tooth retention was estimated from the number of present teeth by multivariate logistic regression analysis using SPSS v. 20.0. RESULTS: In total, 294 (52.8%) subjects retained teeth during a 3-year follow-up period. The number of present teeth and the proportion of subjects with complete tooth retention after 3 years decreased with increasing age. A greater number of present teeth in the baseline year was associated with complete tooth retention after 3 years in a greater proportion of subjects (p < 0.001). Logistic regression analysis revealed that the proportion of subjects with tooth retention in the Q4 quartile (28 teeth) was 9.17 times that in the Q1 quartile (less than 26 present teeth), even after adjusting for sociodemographic factors and oral health behavior in middle-aged individuals. In elderly individuals, tooth retention in the Q4 quartile (28 teeth) was 4.50 times that in the Q1 quartile (less than 17 teeth). CONCLUSIONS: The number of present teeth could be used to estimate tooth retention over a 3-year period. This highlights the importance of promoting oral health care in middle-aged individuals before tooth loss occurs.

Socioeconomic status and self-reported periodontal symptoms in community-dwelling individuals: data from the Korea Community Health Surveys of 2011 and 2013.

OBJECTIVES: This study aimed to evaluate the association between socioeconomic status and self-reported periodontal symptoms. MATERIALS AND METHODS: In this cross-sectional study, data were used from the 2011 and 2013 Community Health Surveys. The 210,432 (weighted n = 36,294,413) and 220,396 (weighted n = 39,067,134) subjects, respectively, were aged 19 years or older. Proportional and systematic sampling was performed. Surveys were conducted by trained interviewers using computer-assisted personal interviewing. The proportions of subjects with tooth mobility, gingival swelling, calculus and gingival bleeding were calculated. Independent variables included sex, age and socioeconomic status measures (education, occupation and income). Differences in the self-reported periodontal symptoms rates according to socioeconomic status were determined using independent t-tests and one-way analysis of variance. Logistic regression analysis was used to identify the association of periodontal symptoms with socioeconomic status. RESULTS: Approximately 30% of the subjects reported at least one symptom of periodontal disease; 11.3% and 9.6% reported gingival bleeding and gingival swelling, respectively, while 5.6% and 3.5% reported dental calculus and tooth mobility, respectively. There were significant associations with self-reported periodontal symptoms according to occupation, education and income (P < 0.01). CONCLUSIONS: The severity of self-reported periodontal symptoms differed according to socioeconomic status. Subjects with lower socioeconomic status reported more advanced periodontal disease symptoms, such as gingival swelling, while those with higher socioeconomic status reported more incipient periodontal symptoms, such as gingival bleeding. Socioeconomic status remains a factor affecting self-reported periodontal symptoms in community-dwelling individuals in Korea.

Provision of oral hygiene services as a potential method for preventing periodontal disease and control hypertension and diabetes in a community health centre in Korea.

This study aimed to evaluate the effects of a community-based oral hygiene service on general and periodontal health indicators of patients with hypertension and type 2 diabetes mellitus visiting a community health centre in Korea. The study used a one-group pretest-posttest and interrupted time-series design. A total of 151 participants (45% male), with a mean age of 63 ± 8.4 years, were included in the study; these included patients with hypertension (62%), diabetes (12%) and both hypertension and diabetes (26%). Two dental hygienists dedicated 2 days per week to this project, providing oral hygiene services to 10-13 participants per day. Four oral hygiene service sessions were provided per patient. The objective oral hygiene status and subjective self-reported periodontal status were compared before and after the service. The changes in blood pressure and glycosylated haemoglobin levels were also assessed. A lower frequency of subjective swelling was reported at the fourth session (37.9%) compared to the first (55.6%) session. Further, significantly fewer cases of calculus and bleeding were observed (p < .05), and significantly more patients reported having no gum problems at the fourth session (43.1% vs. 27.2%; p < .05) than at the first session. Finally, the participants maintained stable blood pressures at each of the four sessions, and their glycosylated haemoglobin levels were significantly lower at the fourth session. In conclusion, the findings of this study suggest that community oral hygiene services provided by dental hygienists can promote objective oral hygiene and subjective periodontal status in the local community, and may help in the control of hypertension and diabetes.

A liquid chromatographic method for the determination of histamine in immunoglobulin preparation using solid phase extraction and pre-column derivatization.

An immunoglobulin (IgG) preparation with micro-amount of histamine fixed on the active protein fraction has been used to increase the resistance to allergic reactions. However, excessive histamine may cause hypo- or hypertension, headache, or anaphylactic shock and so the histamine content of the drug is strictly controlled by a regulation: 0.15 microg of histamine dihydrochloride is allowed for 12 mg of immunoglobulin. In this study, a liquid chromatographic method to determine micro-amount of histamine in the pharmaceutical was developed and validated. This method include a sample cleanup by a solid phase extraction (SPE) using a polystyrene-divinyl benzene (PS-DVB) polymeric sorbent and high-performance liquid chromatography after precolumn fluorescent labeling of the histamine with o-phthaldialdehyde. The drug sample was loaded to the SPE cartridge after adjusting to pH 9.5. After successive washings of the cartridge with water and 30% aqueous methanol, histamine was then eluted with 100 mM sodium acetate (pH 9.5)-methanol (20:80, v/v). An aliquot from the eluate was labeled with o-phthaldialdehyde-mercaptoethanol (OPA-ME) for fluorescence detection at the excitation maximum of 340 nm and emission maximum of 450 nm. HPLC analysis was performed on a phenyl-hexyl column with an acetonitrile-phosphate buffer (pH 6.8; 50 microM) (35:65, v/v) as the mobile phase. The retention times of histamine and 3-methylhistamine (IS) were approximately 7.2 and 9.5 min, respectively. The quantitation range was between 0.01-0.2 mg/mL of histamine showing good linearity (r=0.9996). This analytical method would provide a potential mean for the strict control of histamine content in the pharmaceutical product.