Decomposing socioeconomic inequalities in dental caries among Chinese adults: findings from the 4th national oral health survey.

OBJECTIVE: This cross-sectional study aimed to investigate socioeconomic inequalities in dental caries among adults (35 years and older) in China and explore the contributions of various factors to these inequalities. METHODS: This study included 10,983 adults (3,674 aged 35-44 years, 3,769 aged 55-64 years and 3,540 aged 65-74 years) who participated in the 4th National Oral Health Survey (2015-2016) in China. Dental caries status was evaluated by the decayed, missing and filled teeth (DMFT) index. Concentration indices (CIs) were applied to quantify the different degrees of socioeconomic-related inequality in DMFT, decayed teeth with crown or root caries (DT), missing teeth due to caries or other reasons (MT), and filled teeth without any primary or secondary caries (FT) among adults of different age groups. Decomposition analyses were conducted to identify the determinants and their associations with inequalities in DMFT. RESULTS: The significant negative CI indicated that DMFT for the total sample were concentrated among socioeconomically disadvantaged adults (CI = - 0.06; 95% confidence interval [CI], - 0.073 to - 0.047). The CIs for DMFT for adults aged 55-64 and 65-74 years were - 0.038 (95% CI, - 0.057 to - 0.018) and - 0.039 (95% CI, - 0.056 to - 0.023), respectively, while the CI for DMFT for adults aged 35-44 years was not statistically significant (CI = - 0.002; 95% CI, - 0.022 to 0.018). The concentration indices of DT were negative and concentrated in disadvantaged populations, while FT showed pro-rich inequalities in all age groups. Decomposition analyses showed that age, education level, toothbrushing frequency, income and type of insurance contributed substantially to socioeconomic inequalities, accounting for 47.9%, 29.9%, 24.5%,19.1%, and 15.3%, respectively. CONCLUSION: Dental caries was disproportionately concentrated among socioeconomically disadvantaged adults in China. The results of these decomposition analyses are informative for policy-makers attempting to develop targeted health policy recommendations to reduce dental caries inequalities in China.

Income-related inequality and decomposition of edentulism among aged people in China.

BACKGROUND: The aim of this study was to assess the income-related inequality of edentulism among the aged in China and identify the contributing factors. METHODS: A secondary analysis of data from the 4th National Oral Health Epidemiology Survey in China was conducted, and 65-74 years old were selected for the analysis of income-related inequality of edentulism. The concentration curve, Concentration index (CI) and Erreygers-corrected concentration index (EI) were used to represent inequality and its degree qualitatively and quantitatively, respectively. A decomposition method based on probit model was employed to determine the contributors of inequality, including demographic factors, income status, oral health-related knowledge, attitude and practices and self-perceived general health status. RESULTS: In China, aged people with edentulism were concentrated in the poor. The CI was - 0.2337 (95% CIs: - 0.3503, - 0.1170). The EI was - 0.0413 (95% CIs: - 0.0619, - 0.0207). The decomposition results showed that income (75.02%) and oral health-related knowledge, attitude and practices (15.52%) were the main contributors to the inequality. CONCLUSION: This study showed that pro-poor inequality among the elderly with edentulism existed in China. Corresponding policies against the contributors could be considered to promote the health equality of the elders.

Socioeconomic-related inequality in dental care utilization among preschool children in China.

OBJECTIVES: This study aimed to investigate socioeconomic-related inequality in dental care service utilization in the past 12 months among Chinese preschool children and to explore the contribution of various factors to this inequality. METHOD: A total of 40 305 children aged 3-5 years from 372 kindergartens who participated in the Fourth National Oral Health Survey in China were included in the final analysis. The method of data weighting in complex sampling was adopted to make the samples more representative. Erreygers-corrected concentration index (EI) was used to measure socioeconomic-related inequality in dental care service utilization. The horizontal inequality index (HI) was employed to analyse horizontal inequality. Decomposition analyses were conducted to explore the contributions of income level, need variables (dmft, caregiver-evaluated oral health status and toothache experience) and nonneed variables (caregiver education level, residential location, age, and sex) to the inequality of health service utilization. RESULT: The utilization of oral health services within the past 12 months among the high-, middle- and low-income groups was 17.4% (95% CI: 15.6-19.3), 13.6% (95% CI: 12.2-15.1) and 9.4% (95% CI: 8.1-11.0) respectively. The concentration curve was below the line of equality, and the EI and HI were 0.072 and 0.078, respectively, indicating that dental care utilization in children aged 3-5 years was concentrated in those who were better off. The contribution of the need variables to socioeconomic-related inequality in dental services was minimal, and most dental care utilization inequality could be explained by household income, caregiver education attainment and urban-rural disparities, accounting for 32.0%, 49.4% and 20.4% respectively. CONCLUSION: This study reveals the existence of pro-rich inequality in dental care utilization among preschool children in China. The decomposition analysis suggests that income, caregiver education background and urban-rural disparities are the main factors contributing to this outcome. Equity-oriented policies and programmes are needed to achieve equitable dental care utilization.

Measuring and decomposing socioeconomic-related inequality in the use of oral health services among Chinese adults.

OBJECTIVES: This study aimed to measure socioeconomic-related inequality and horizontal inequity in the use of oral health services and decompose this inequality among adults of different age groups in China. METHODS: In total, 10 973 adults (3669 aged 35-44 years, 3767 aged 55-64 years and 3537 aged 65-74 years) who participated in the 4th National Oral Health Survey (2015-2016) in China were included. Concentration curves and the Erreygers-corrected concentration index (EI) were employed to measure socioeconomic-related inequality in the use of oral health services. Then, inequity in this utilization was measured by the horizontal inequity index (HI). Furthermore, decomposition analyses were conducted for the three groups to explain the contributions of income level, need factors (ie self-assessed oral health and evaluated oral health status), other factors (ie sex, residential location, educational attainment level and type of basic insurance) and a residual term to overall inequality in oral health service utilization. RESULTS: The significant positive EI and HI values indicated that pro-rich inequality and inequity in oral health service utilization exist among Chinese adults. Income and type of basic medical insurance contributed the most to socioeconomic-related inequality in the use of oral health services among adults aged 55-64 and 65-74 years. However, the main driving factors of socioeconomic inequality among adults aged 35-44 years in dental care use included income, educational achievement, type of basic medical insurance and residential location. The need variables accounted for a very small proportion of overall socioeconomic-related inequality in oral health service use in all three groups. CONCLUSIONS: Oral healthcare service utilization was disproportionately concentrated among better-off Chinese adults. The primary determinants of inequality in dental care use in different age groups provide information for policymakers to create more targeted policies to achieve equity in the oral healthcare system in China.

Utilization of dental services and associated factors among preschool children in China.

BACKGROUND: This study sought to evaluate dental utilization among 3-,4-, and 5-year-old children in China and to use Andersen's behavioural model to explore influencing factors, thereby providing a reference for future policy making. METHODS: This study is a cross-sectional study. Data of 40,305 children aged 3-5 years were extracted from the Fourth National Oral Health Survey, which was performed from August 2015 to December 2016. Patient data were collected using a questionnaire, which was answered by the child's parents, and clinical data were collected during a clinical examination. Stratification and survey weighting were incorporated into the complex survey design. Descriptive statistics, bivariate correlations and hierarchical logistic regression results were then analysed to find the factors associated with oral health service utilization. RESULTS: The oral health service utilization prevalence during the prior 12 months were 9.5% (95%CI: 8.1-11.1%) among 3-year-old children, 12.1% (95%CI: 10.8-13.5%) among 4-year-old children, and 17.5% (95%CI: 15.6-19.4%) among 5-year-old children. "No dental diseases" (71.3%) and "dental disease was not severe" (12.4%) were the principal reasons why children had not attended a dental visit in the past 12 months. The children whose parents had a bachelor's degree or higher (OR: 2.29, 95%CI: 1.97-2.67, p < 0.001), a better oral health attitude ranging from 5 to 8(OR: 1.64, 95%CI: 1.43-1.89, p < 0.001), annual per capital income more than 25,000 CNY (OR: 1.40, 95%CI: 1.18-1.65, p < 0.001),think their child have worse or bad oral health (OR: 3.54, 95%CI: 2.84-4.40, p < 0.001), and children who often have toothaches (OR: 9.72, 95%CI: 7.81-12.09, p < 0.001) were more likely to go to the dentist in the past year. CONCLUSION: The prevalence of dental service utilization was relatively low among preschool children. It is necessary to strengthen oral health education for parents and children, thereby improving oral health knowledge as well as attitude, and promoting dental utilization.

Factors associated with oral health service utilization among adults and older adults in China, 2015-2016.

OBJECTIVES: To explore the factors associated with utilization of oral health services among Chinese adults and older adults according to the Andersen Behavior Model. METHODS: Data from the 4th National Oral Health Survey (2015-2016) in China were used. A total of 7206 people (3669 adults aged 35-44 years and 3537 older adults aged 65-74 years) were included in our analysis. Oral health service utilization in the past 12 months was the outcome variable. Explanatory variables were selected according to the Andersen Behavior Model. Descriptive statistics and bivariate associations (chi-square tests) were analysed, followed by hierarchical Poisson regression models, which were conducted to determine the factors associated with oral health service utilization. RESULTS: In total, 21.4% (95% CI: 19.4%-23.7%) of adults (35-44 years old) and 20.7% (95% CI: 18.6%-22.9%) of older adults (65-74 years old) utilized oral health services in the past 12 months. Nearly 80% of adults (78.7%, 95% CI: 74.0%-82.7%) and more than 90% of older adults (93.7%, 95% CI: 91.0%-95.6%) visited a dentist for treatment. Adults aged 35-44 years old who were female (IRR: 1.15, 95% CI: 1.00-1.33, P = .047), had good oral health knowledge and attitudes (IRR: 1.30, 95% CI: 1.06-1.59, P = .011), perceived their oral health status as fair (IRR:1.51, 95% CI:1.24-1.85, P < .001) or poor/very poor (IRR:2.52, 95% CI:2.01-3.18, P < .001) and had a decayed, missing and filled teeth (DMFT) index >0 (IRR: 1.52, 95% CI: 1.11-2.09, P = .009) were more likely to report dental visits in the past 12 months. Older adults who utilized oral health services tended to be female (IRR: 1.32, 95% CI: 1.09-1.59, P = .004); to be covered by Urban Resident Basic Medical Insurance (URBMI) (IRR: 1.56, 95% CI: 1.18-2.05, P = .002), Urban Employee Basic Medical Insurance (UEBMI) (IRR: 1.69, 95% CI: 1.32-2.16, P < .001) or government medical insurance (GMI) (IRR: 1.03, 95% CI:1.01-2.16, P = .044); to have a high education level (IRR: 1.37, 95% CI: 1.08-1.74, P = .010); to have an income level in the 2nd tertile (IRR: 1.44, 95% CI: 1.13-1.84, P = .003) or 3rd tertile (IRR:1.52, 95% CI:1.18-1.95, P = .001); and to perceive their oral health status as poor or very poor (IRR: 1.53, 95% CI: 1.21-1.95, P = .001). CONCLUSIONS: Sex and self-perceived oral health status were associated with oral health utilization among Chinese population. Additionally, for older adults, education level, household income and insurance coverage were determinants of dental service use. These findings can aid in creating more targeted policies to increase the use of dental services by Chinese adults.

Prevalence and Indicators of Tooth Wear among Chinese Adults.

Numerous epidemiological studies have focused on the prevalence and related indicators of tooth wear. However, no sufficient studies have been conducted with Chinese adults. The purpose of this study was to assess the prevalence of tooth wear and identify related indicators among adults aged 36 to 74 years in Wuhan City, P.R. China. A cross-sectional and analytic study was conducted with 720 participants, aged 35-49 yrs and 50-74 yrs, in 2014. Each age group included 360 participants, of which 50% were males and 50% were females. All participants completed a questionnaire before examination. Tooth wear was assessed using the modified Basic Erosive Wear Examination (BEWE) index. The data were analyzed using the chi-square test and binary logistic regression analysis. The prevalence of tooth wear was 67.5% and 100% in the 35-49 and 50-74 age groups, respectively. The prevalence of dentin exposure was 64.7% and 98.3%, respectively. A significantly higher prevalence of tooth wear and dentin exposure was found in the 50-74 yr group than in the 35-49 yr group (p < 0.05). Critical indicators of tooth wear and dentin exposure included high frequency of acidic drinks and foods consumption, low socio-economic status, and unilateral chewing. The frequency of changing toothbrushes and the habit of drinking water during meals were associated with tooth wear. In addition, the usage of hard-bristle toothbrushes and consuming vitamin C and aspirin were found to be linked with dentin exposure. In conclusion, the prevalence of tooth wear and dentin exposure observed in Chinese adults was high, and the results revealed an association between tooth wear and socio-behavioral risk indicators.

Inequalities in dental caries among 12-year-old Chinese children.

OBJECTIVE: To explore whether there are socioeconomic, ethnic, and geographical inequalities in dental caries among 12-year-old Chinese children. METHODS: Data from 2,307 12-year-old children living in Guangxi, Hubei, Jilin, and Shanxi and who participated in the Third National Oral Health Survey in China were used for this study. Data were collected through structured questionnaires and clinical examinations with children. The decayed, missing, and filled permanent teeth (DMFT) index and number of decayed teeth (DT) were the outcome measures for analysis. Inequalities in DMFT and DT by socioeconomic position (parental education), ethnicity, and geography (province of residence and urbanicity) were assessed in unadjusted and adjusted negative binomial regression models. RESULTS: Ethnicity and geographical factors, but not parental education, were significantly associated with childhood dental caries in unadjusted models. However, only geographical factors remained significantly related to dental caries after mutual adjustments. The DMFT index and DT were higher among children living in Jilin and Guangxi than those of children living in Hubei and Shanxi, and also higher among children living in rural areas than in those living in urban areas. CONCLUSION: This analysis shows inequalities in dental caries among 12-year-old children in four provinces of China. There were considerable inequalities in children's DMFT and number of decayed teeth by geography but not by ethnicity or parental education.

Self-assessed dental health, oral health practices, and general health behaviors in Chinese urban adolescents.

The objectives of this study were: to describe perceived dental health status and oral health-related knowledge, attitudes, and behavior in Chinese urban adolescents; to assess the associations of oral health variables with socio-economic status and school performance; and to analyse the relative effect of socio-behavioral risk factors on perceived dental health, perceived need for dental care, and experience of dental symptoms. A cross-sectional survey of 2662 adolescents was conducted in eight capital cities in China; the response rate was 92%. The study population was chosen by multistage cluster sampling and covered three age groups: 11, 13, and 15 years. Data on dental and general health were collected by self-administered questionnaires. Self-assessment of dental health of Chinese adolescents was generally good, only 12% of the students answered that their teeth were "poor" or "very poor", and 9% claimed having "poor" or "very poor" gums. Eleven percent of participants said that other students made fun of their teeth; 24% of the respondents were dissatisfied with the appearance of their teeth, and 41% claimed that they had experienced toothache or symptoms during the previous 12 months. Positive attitudes towards dental care were found in all age groups; 67% of adolescents brushed their teeth at least twice a day and 48% of the students used fluoridated toothpaste. Only 26% of the students visited a dentist during the previous 12 months. In all, 6% of the adolescents had tried cigarette smoking at least once, while 41% reported having tasted alcohol drinks. Multivariate regression analyses showed that perceived dental health status and needs were associated with gender, age, unhealthy lifestyles, poor school performance, and socio-economic status. The establishment of school-based health promotion programs in China is urgently needed, and promotion of oral health lifestyles should be integrated with other general health actions.