Decomposing Socioeconomic Inequality in Early Childhood Caries Among 3 to 5-Year-Old Children in China.

INTRODUCTION AND AIMS: Early childhood caries (ECC) is a widespread oral disease that harms children's health in China. Although previous studies have linked ECC prevalence to socioeconomic status, few have measured the degree of socioeconomic inequality. This study aimed to evaluate the socioeconomic inequality of ECC in children aged 3 to 5 years in China and identify the contributor to the inequality. METHODS: We extracted data on 3 to 5-year-old children from the fourth National Oral Health Survey. We measured the inequality of ECC by the average household income per capita. We used the average household income per capita to measure the inequality of ECC. To describe inequality both qualitatively and quantitatively, we used the following methods: concentration curve, Erreygers-corrected concentration index, relative index of inequality and slope index of inequality. We also applied a decomposition based on the probit model to identify the factors that contributed to inequality. RESULTS: The prevalence of ECC in Chinese preschool children was 63.11% (95% CIs: 60.54%, 65.61%). The negative value of the Erreygers-corrected concentration index (-0.0459; 95% CIs: -0.0594, -0.0324), slope index of inequality (-0.0674; 95% CIs: -0.0876, -0.0471) and the positive value of relative index of inequality (0.7484; 95% CIs: 0.6856, 0.8169) all indicated that ECC prevalence was higher among children from low-income families. The main factors contributing to inequality were average household income, parents' educational level and living areas. CONCLUSION: There is a pro-poor inequality in ECC among 3 to 5-year-old children in China. CLINICAL RELEVANCE: To improve oral health equality, policymakers should focus more on children from low-income families, with less educated parents and living in rural areas.

Long-term exposure to ambient fine particulate matter and periodontitis: An observational study using nationally representative survey data.

AIM: The rising prevalence of periodontitis imposes substantial burdens on individuals and society. Identifying environmental risk factors for periodontitis may contribute to tackling the global public health burden of it. This study aimed to assess the association between long-term exposure to PM2.5 and periodontitis in a nationally representative population from China. MATERIALS AND METHODS: In this multi-centre cross-sectional study of 372 communities in 31 provinces of Mainland China, we used data from the Fourth National Oral Health Survey of China in 2015-2016, in combination with high-resolution gridded concentrations of fine particulate matter (PM2.5). Logistic regression was applied to assess the relationship between long-term PM2.5 exposure and the risk of periodontitis. In addition, we examined whether the association varied by individual characteristics, and estimated the exposure-response relationship and the risk of damaged tooth in each tooth quadrant. RESULTS: A total of 8391 participants from 96 cities were diagnosed with periodontitis, accounting for 60.04% (8391/13,459) of the participants. For each 10 µg/m3 increment in 1-, 3- and 5-year average concentrations of PM2.5, the risk of total periodontitis increased by 9.0% (95% confidence interval: 6.0%, 12.0%), 8.0% (6.0, 11·0) and 7.0% (5.0, 10.0), respectively. Mild periodontitis was more strongly associated with PM2.5 exposure than moderate and severe periodontitis. The teeth in the lower anterior, lower posterior or upper anterior are more susceptible to the effect of PM2.5 on the periodontal pocket, calculus and bleeding gums. CONCLUSIONS: Long-term exposure to PM2.5 is significantly associated with an increased risk of periodontitis in the nationally representative Chinese population. Considering the rising prevalence of periodontitis, considerable costs of treatment, and substantially adverse effects on individuals and society, these findings suggest that stricter air quality regulations may help ease the burden of periodontal disease.

Epidemiology of plaque-induced gingivitis among 12-15-year-old Chinese schoolchildren: A study based on the 2018 case definition.

AIM: To explore the epidemiology of plaque-induced gingivitis and related factors among Chinese adolescents. MATERIALS AND METHODS: This cross-sectional survey comprised 118,601 schoolchildren in the 12-15-year age group. Data came from the National Oral Health Survey in mainland China. The field investigation was conducted according to the World Health Organization guidelines. The new 2018 case definition for plaque-induced gingivitis was used. Participants underwent clinical examinations and completed a structured questionnaire. Bleeding on probing (BOP) was performed on all teeth. Multinomial logistic regression was used to explore the factors related to the extent of gingivitis. RESULTS: Nearly half of the study population (47.3%) had plaque-induced gingivitis; 23.9% and 23.3% presented with localised and generalised gingivitis, respectively. The first molars were the most affected by BOP. Well-established factors, such as demographic characteristics, socioeconomic status, local factors and smoking habits, were significantly associated with the extent of gingivitis. Odds ratios for localised and generalised gingivitis increased with the decrease in frequency of toothbrushing with a fluoride dentifrice. CONCLUSIONS: The study population had high plaque-induced gingivitis prevalence. The extent of gingivitis appeared to have a dose-response relationship with the frequency of toothbrushing with a fluoride dentifrice.

Tooth brushing with fluoridated toothpaste and associated factors among Chinese adolescents: a nationwide cross-sectional study.

BACKGROUND: Tooth brushing with fluoridated toothpaste has become the most important way to provide the anti-caries effect of fluoride around the world. China has promoted the use of fluoridated toothpaste since 1989. However, there are few studies on the national profile of use of fluoridated toothpaste and related factors in Chinese adolescents. We carried out this study to investigate oral hygiene behaviours, especially the status of tooth brushing with fluoridated toothpaste and its correlates among adolescents, based on data from the latest Nation Oral Health Survey in mainland China. METHODS: This cross-sectional study recruited 118,601 participants aged 12-15 years using multistage stratified sampling. Questionnaires were completed by students at school. Data employed in analyses were extracted from the questionnaire, including information on tooth brushing, fluoridated toothpaste, dental floss, sociodemographic factors, fluoride knowledge and attitude towards regular dental check-ups. A binary logistic regression was performed to compute the odds ratios (OR). Tooth brushing twice daily with fluoridated toothpaste was the dependent variable. Sociodemographic factors, fluoride knowledge, attitude towards regular dental check-ups, dental visit experience and perceived oral health were the independent variables. P < 0.05 was considered statistically significant. RESULTS: A total of 32.6% of participants brushed their teeth twice daily, 7.4% used fluoridated toothpaste, and 3.9% cleaned their teeth twice daily with fluoridated toothpaste. The logistic regression showed the probability of twice-a-day tooth brushing with fluoridated toothpaste was higher among these groups: females (OR: 1.141; 95%CI: 1.072-1.214), 15-year-olds (OR: 1.786; 95%CI: 1.634-1.952), from urban areas (OR: 1.389; 95%CI: 1.288-1.497), without siblings (OR: 1.351; 95%CI: 1.259-1.450), with an educated father (OR: 1. 605; 95%CI: 1.442-1.788) and mother (OR: 1.706; 95%CI: 1.530-1.903), having dental visit experiences (OR: 1.702; 95%CI: 1.589-1.823), rating one's oral health as good (OR: 2.341; 95%CI: 2.083-2.631), having fluoride knowledge (OR: 4.345; 95%CI: 4.034-4.678) and having a positive attitude towards regular dental check-ups (OR: 1.589; 95%CI: 1.460-1.729). CONCLUSIONS: The oral hygiene behaviours of Chinese adolescents were undesirable. Twice daily tooth brushing with fluoridated toothpaste was significantly associated with sociodemographic factors, fluoride knowledge, and attitudes towards regular dental check-ups.

Association between oral health and cognitive function among Chinese older adults: the Taizhou imaging study.

BACKGROUND: We aimed to investigate the association between oral health and cognitive function in a sample of older adults from a Chinese rural community. METHODS: The cross-sectional cognitive function of 677 individuals were assessed by Mini-Mental State Examination (MMSE) and Montreal Cognitive Assessment (MoCA). A comprehensive profile of the oral health status was evaluated by questionnaire and clinical examination. RESULTS: Multiple covariates-adjusted regression models demonstrated decayed teeth (DT) and decayed/missing/filled teeth (DMFT) were negatively associated with MoCA score (all p < 0.05). Calculus index (CI) and clinical attachment loss (CAL) were significantly associated with the lower MoCA, short-term memory and executive function score, respectively (all p < 0.05). Additionally, participants with missing teeth unrestored tend to get lower MMSE and MoCA scores (p < 0.05). The results also showed that increased DT and CI were modestly associated with higher odds of cognitive impairment (p < 0.05). CONCLUSIONS: There is an association between oral health and global cognition. Poor periodontal status was strongly associated with worse global cognition performance, especially in the short-term memory and executive domain for the aging population.

Heavy metals in drinking water and periodontitis: evidence from the national oral health survey from China.

BACKGROUND: Periodontitis has become an increasingly important public health issue, coupled with a high economic burden for prevention and treatment. Exposure to essential trace heavy metals has been associated with various diseases; however, the relationships between essential trace heavy metals and periodontitis remain inconclusive. OBJECTIVES: To investigate the association between essential trace heavy metals in tap water and periodontitis in a nationally representative sample in China. METHODS: We conducted a nationwide study including 1348 participants from the Fourth National Oral Health Survey in the 2015-2016 period. The trace heavy metals concentration was measured in the local pipeline terminal tap water. Periodontitis was diagnosed according to the classification scheme proposed at the 2018 world workshop on the classification of periodontal and peri-implant diseases and conditions. We used weighted multivariable logistic regression to estimate the association between essential trace heavy metals and the risk of periodontitis. We additionally used spline analysis to explore the possible nonlinear dose-response associations. RESULTS: Periodontitis patients were exposed to higher concentrations of essential trace heavy metals. In adjusted models, for 1 SD increase in the concentration of iron, manganese, and copper in tap water, the risk of periodontitis increased by 30% (OR: 1.30, 95%CI: 1.12-1.50), 20% (OR: 1.20, 95%CI: 1.03-1.41), and 20% (OR: 1.20, 95%CI: 1.04-1.39), respectively. Stratified analyses demonstrated that the associations between essential trace heavy metals and periodontitis were higher in females, elders, and rural residents. Spline analysis revealed nonlinear exposure-response relationships between periodontitis and exposure to iron, manganese, and copper in tap water. CONCLUSIONS: Exposures to essential trace heavy metals in drinking water were associated with greater odds of periodontitis. Given the growing burden of periodontitis, our study sheds light on tailored public health policies for improving drinking water standards to alleviate periodontitis impairment.

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.

Association between periodontitis and hypertension: cross-sectional survey from the Fourth National Oral Health Survey of China (2015-2016).

OBJECTIVES: To evaluate the association between periodontitis severity and hypertension based on Chinese epidemiological data. DESIGN: This cross-sectional survey enrolled adults from the Fourth National Oral Health Survey of China (2015-2016). SETTING: The data were obtained from the Fourth National Oral Health Survey of China (2015-2016). PARTICIPANTS: The study included individuals aged 35-44 years (n=4409), 55-64 years (n=4568) and 65-74 years (n=4218). PRIMARY AND SECONDARY OUTCOME MEASURES: Periodontal status, defined on the basis of the 2017 classification scheme, and periodontal parameters (eg, bleeding on probing (BOP)) were compared between individuals with hypertension and individuals with normotension. Smoothed scatterplots were constructed to demonstrate the associations of periodontal parameters and periodontal status with hypertension. RESULTS: Severe periodontitis (stages III and IV) was present in 41.4% of individuals with hypertension and 28.0% of individuals with normotension, respectively (p<0.001). The prevalence of severe periodontitis was higher in individuals with hypertension than that in individuals with normotension among participants aged 35-44 years (18.0% vs 10.1%, p<0.001) and 55-64 years (40.2% vs 36.7%, p=0.035), but not in participants aged 65-74 years (46.4% vs 45.1%, p=0.429). Therefore, the difference in periodontal status between individuals with hypertension and individuals with normotension decreased with age. There were higher prevalences of BOP, probing depth (PD) ≥4 mm and PD ≥6 mm in individuals with hypertension than in individuals with normotension (52.1% vs 49.2%, 19.6% vs 14.7% and 1.8% vs 1.1%, respectively). Periodontitis severity and the proportion of teeth with PD ≥4 or ≥6 mm were positively associated with hypertension. CONCLUSION: Periodontitis is associated with hypertension in Chinese adults. Hypertension prevalence increased with periodontitis severity, particularly among young participants. Accordingly, it is necessary to improve the education, awareness of periodontal treatment and preventive management among individuals at risk of hypertension, particularly in the younger population.

Relationship between chronic periodontitis and inflammatory cytokines in patients undergoing maintenance hemodialysis.

OBJECTIVES: To investigate the correlation between serum and gingival crevicular fluid (GCF) levels of inflammatory cytokines and the association with periodontal parameters in patients with maintenance hemodialysis (MHD) and healthy control. MATERIALS AND METHODS: Patients who were undergoing MHD were enrolled as the MHD group. Healthy individuals who underwent oral examination were selected as the control group after matching for the MHD group. All participants underwent a full-mouth periodontal evaluation, and the levels of eight inflammatory cytokines, including IL-1ß, IL-17, IL-6, IL-8, and tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase-8 (MMP-8), and C-reactive protein (CRP), in the GCF and serum were measured. RESULTS: A total of 63 MHD patients and 75 healthy persons were included. The prevalence of moderate/severe periodontitis was significantly higher in the MHD group than in the control group (88.9 vs. 66.7%, P < 0.05). The GCF levels of CRP, TNF-α, MCP-1, and MMP-8 were higher in patients in the MHD group with moderate/severe periodontitis than in the control group (P < 0.05). Serum CRP, MCP-1, TNF-α, and MMP-8 levels were positively correlated with the GCF CRP levels (P < 0.05). The GCF and serum CRP levels were positively correlated with the periodontal clinical parameters (P < 0.05). CONCLUSIONS: Serum CRP, MCP-1, TNF-α, and MMP-8 may relate with the GCF CRP levels. The GCF and serum CRP levels correlated positively with the periodontal clinical parameters, including the VPI, PPD, and CAL, indicating that CRP may play an important role between periodontitis and ESRD. CLINICAL RELEVANCE: The present study indicated that GCF and serum CRP levels correlated positively with the periodontal clinical parameters, and the CRP levels may be selected as an indicator to evaluate the severity of inflammation and the effectiveness, prognosis of periodontal treatment in ESRD patients.

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.

Epidemiological and Microbiome Characterization of Black Tooth Stain in Preschool Children.

OBJECTIVE: To assess the epidemiologic attributes and microbial variations associated with extrinsic black tooth stain (BTS) among Chinese preschool children. METHODS: This cross-sectional study included 250 preschool children (3-4 years) from three kindergartens in Shanghai, China. Following clinical examination, and using a case-control design, saliva and dental plaque specimens were collected from caries-free participants with (n = 21, BTS group) and without (n = 48, control group) BTS. The chi-square test and logistic regression model were used to evaluate factors associated with BTS. 16S rRNA sequencing were used to characterize the associated microbial communities. RESULTS: BTS was detected in 12.4% of participants, with a mean of 13.7 black-stained teeth. Participants with BTS had a lower caries burden and better oral hygiene (P = 0.003). Children with less frequent intake of marmalade or honey (P = 0.033) and regular application of fluoride (P = 0.007) had a lower likelihood of having BTS. Microbiota analysis revealed 14 phyla, 35 classes, 63 orders, 113 families, 221 genera, 452 species, and 1,771 operational taxonomic units (OTUs). In terms of microbial diversity, no significant differences were observed in the saliva of the two groups (P > 0.05). Dental plaque from the BTS group exhibited higher OTU richness but lower evenness than that from the control group (Chao P = 0.006, Shannon P = 0.007, respectively) and showed a significant difference in ß diversity (P = 0.002). The microbiome in the two groups was characterized by various microbial biomarkers, such as Pseudomonas fluorescens, Leptotrichia sp._HMT_212, Actinomyces sp._HMT_169, and Aggregatibacter sp._HMT_898 in plaques from the BTS group. Functional analysis of the microbial species suggested the existence of a hyperactive metabolic state on teeth surfaces with BTS plaques and revealed that ferric iron, the iron complex transport system, and the iron (III) transport system were more abundant in BTS plaque samples. CONCLUSIONS: This study provides insights into the epidemiologic and microbial features of BTS in preschool children. The microbiome in BTS is characterized by various microbial biomarkers, which can serve as indicators for BTS diagnosis and prognosis.

Redondoviridae infection regulates circRNAome in periodontitis.

Redondoviridae is a recently identified family of DNA viruses associated with periodontitis. Circular RNAs (circRNAs) are novel endogenous, conserved noncoding RNAs contributing to the virus-related immune-inflammatory response. This study aimed to analyze the expression profiles of circRNAs in the gingival tissues of periodontitis patients with and without Redondoviridae-infection and healthy controls using high-throughput RNA sequencing combined with experimental validation. Out of 17 819 circRNAs, 175 were dysregulated. Functional annotation and enrichment analysis of the differential circRNA host genes demonstrated potential alterations in the molecular and cellular components and metabolism in individuals suffering from periodontitis with Redondoviridae infection. Moreover, "axon guidance," "lysine biosynthesis," and "vascular endothelial growth factor signaling pathways" were significantly enriched in Redondoviridae-infected gingivitis tissues. Furthermore, the key circRNAs (circCOL1A1, circAASS, circPTK2, circATP2B4, circDOCK1, circTTBK2, and circMCTP2) associated with the pathobiology of Redondoviridae-related periodontitis were identified by constructing circRNA-micro RNA (miRNA)-messenger RNA (mRNA) networks. Bioinformatics analyses demonstrated that abnormally expressed circRNAs might contribute to the etiopathogenesis and development of Redondoviridae-related periodontitis. This study's findings have enhanced the current understanding of the Redondoviridae-related periodontitis mechanism and provide insights into further applications for diagnostic markers and therapeutic uses.

Microbiota of preterm infant develops over time along with the first teeth eruption.

Objective: The temporal growth of the infant microbiome in the early years of life influences short- and long-term infant health. The aim of this longitudinal study was to investigate bacterial dynamics in the microbiome of preterm infants during tooth eruption. Methods: Saliva samples from normally delivered (n = 24) and preterm infants (n = 31) were collected 30 days after birth and after the eruption of two primary mandibular incisors. Based on Illumina MiSeq Sequencing of the 16S rRNA gene, the dynamic microbial changes of newborns at two-time points were investigated. Meanwhile, the Human Oral Microbiome Database was adopted for assigning taxonomy. Results: Using alpha and beta diversity analyses, different shift patterns of microbiome structures in preterm and healthy participants and bacterial diversity over time were observed. The relative abundance and shifts trend, along with the two lower primary central incisors eruption, of core oral flora varies in full-term and preterm groups, including Gemella spp., Rothia mucilaginosa, Veillonella atypica, etc. Several microorganisms colonize later in the oral microbiome development of premature babies, such as Gemella spp. In addition to teeth eruption, the growth of the saliva microbiome in preterm infants could be influenced by breastfeeding durations and birth weight. Conclusion: This study provided insights into how the oral microbiota changes during tooth eruption in preterm infants and how the colonization of the oral cavity with bacteria in preterm infants differs significantly from that in full-term infants.

[Prevalence of torque teno mini virus (TTMV) and epstein-barr virus (EBV) in gingival tissues in 80 patients with periodontitis].

PURPOSE: To study the prevalence of torque teno mini virus (TTMV) and epstein-barr virus(EBV) in patients with periodontitis. METHODS: Gingival tissue samples were collected from 80 patients with periodontitis and 40 periodontal healthy volunteers. The presence of EBV and TTMV-222 were detected by nested PCR, and the virus loads were detected by real-time PCR. Statistical analysis was performed by SPSS 16.0 software package. RESULTS: The detection rates and virus loads of EBV and TTMV-222 in periodontitis group were significantly higher than those in periodontal health group (P＜0.05), and the detection rate of TTMV-222 in EBV positive group was significantly higher than that in EBV negative group (P＜0.01). There was a positive correlation between EBV and TTMV-222 in gingival tissues(P＜0.01). CONCLUSIONS: TTMV infection and co-infection of EBV and TTMV may be related to periodontal disease, but the pathogenic mechanism of the interaction between the two viruses needs further studies.

Trend on dental caries status and its risk indicators in children aged 12 years in China: a multilevel analysis based on the repeated national cross-sectional surveys in 2005 and 2015.

BACKGROUND: This study aimed to explore the trend and risk indicators for dental caries of children aged 12 years in China based on national oral health survey data in 2005 and 2015. METHODS: Research data were from the two latest national oral health surveys conducted in mainland China, including 30 and 31 provinces, autonomous regions, and municipalities in 2005 and 2015, respectively. Children aged 12 years were clinically examined for dental caries and dental fluorosis according to the World Health Organization criteria. Sociodemographic characteristics and oral health-related behaviours were collected using questionnaires. Multilevel zero-inflated negative binomial regression model was used to investigate the association between dental caries severity and dental fluorosis, sociodemographic characteristics, and oral health-related behaviours. RESULTS: The final analyses included 12,350 and 27,818 children surveyed in 2005 and 2015, respectively. The standardized prevalence of dental caries increased from 27.05% (95% confidence interval [CI], 24.25-28.85) in 2005 to 37.92% (95% CI, 34.94-40.90) in 2015, and the respective standardized mean decayed, missing, filled teeth (DMFT) index scores increased from 0.50 (standard deviation [SD], 1.04) to 0.83 (SD, 1.45) (P < 0.001). Fujian province had the highest increase in dental caries, followed by Liaoning, Heilongjiang, Hainan, and Yunnan. Results revealed that children who were girls, more frequently experienced dental pain, and had more recent dental visits, had significantly higher DMFT scores after adjusting for the survey year and other variables (all P < 0.05). CONCLUSIONS: Dental caries of 12-year-old children in China deteriorated from 2005 to 2015, particularly in the northeast and southwest regions. Dental caries was associated with sex, dental pain, and dental service utilization.

Related factors of periodontal health among Chinese middle school students, findings from a national cross-sectional survey.

BACKGROUND: To investigate the related risk factors of periodontal health status among Chinese middle school students. METHODS: This study is a part of the Fourth National Oral Health Epidemiological Survey, which is by far the largest oral epidemiological survey in China, including all provinces, municipalities and autonomous regions in mainland China. A multi-stage stratified sampling method was used to select middle school students aged 12-15 from the sampled middle school for investigation. The survey consisted of two parts: oral examination and questionnaire survey. The oral examination included gingival bleeding and calculus. The questionnaire included sociodemographic information, oral health knowledge, attitudes and behaviors. Logistic regression and generalized linear mixed model were used to investigate the risk factors of gingival bleeding and calculus. RESULTS: A total of 118,514 middle-school students has been examined. Less gingival bleeding (OR = 0.746, CI 0.718-0.774) and calculus (OR = 0.550, CI 0.529-0.527) were found in 12-year-old group compared to 15-year-old group. The periodontal health status of males was worse than that of females (gingival bleeding OR = 1.102, CI 1.074-1.132, calculus OR = 1.258, CI 1.223-1.295). Besides age and gender, region, living place, ethnic groups, family structure, parent's education level, oral health knowledge and behavior were also related to gingival bleeding and calculus. CONCLUSIONS: Gingival bleeding and calculus occurred most of 12-15 years old adolescents in China. Several related factors, such as gender, age, ethnicity, father's education level, oral health knowledge and behavior, were found in multi-factorial models. The impact of province should arouse people's attention.

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.

Dynamic Observation of the Effect of Maternal Caries on the Oral Microbiota of Infants Aged 12-24 Months.

Aim: To provide a dynamic description of the oral microbial composition in mothers with and without dental caries and their children aging 12-24 months. Methodology: A total of 20 pairs of mothers and their children aged 12 months were included and followed up at 18 and 24 months of age. Ten mothers with dental caries(MEG) and their children(CEG) were in the exposure group, and ten caries-free mothers(MCG) and their children(CCG)in control group. Supragingival plaque biofilm samples were collected and DNA was extracted for bacterial 16S rRNA gene sequencing. Results: A total of 18 pairs completed follow-ups. At a 3% divergence level, the number of common operational taxonomic units found between the mothers and children increased as the children aged. Proteobacteria, Bacteroidetes, Firmicutes, Fusobacteria, and Actinobacteria accounted for more than 80% phyla of each group. A microbial community structure analysis showed that the differences between mothers and children were significant in all groups except for the MEG24 and CEG24 groups. Conclusions: Oral microbiota of children was more like their mothers' with increasing age, regardless of whether the mothers had dental caries. Mothers with dental caries may have a greater influence on the oral microbiota of children's than those without dental caries as children age.

Characteristics of biofilm-induced degradation at resin-dentin interfaces using multiple combinations of adhesives and resins.

OBJECTIVE: We aimed to evaluate morphological, mechanical and chemical characteristics at resin-dentin interfaces using multiple combinations of adhesives and resins after a short-term biofilm-induced degradation. METHODS: Cervical cavities were prepared in bovine incisors, treated by Clearfil SE Bond 2 (SE) or FL-Bond II (FL), restored by Clearfil Majesty ES Flow (ES) or Beautifil Flow Plus (BFP) and grouped into SE-ES, SE-BFP, FL-ES and FL-BFP. After biofilm challenge, interfacial gaps and dentin wall lesions were examined by optical coherence tomography (OCT). Gap depth (GD), gap pattern scale (GPS) and dentin wall lesion depth (WLD) were evaluated from confocal laser scanning microscope. Microhardness of dentin lesions was measured with a Vickers microhardness tester. Chemical elements in resins and dentin wall lesions were analyzed by scanning electron microscopy and energy dispersive X-ray spectrometry (SEM/EDS). Morphological structures of interfacial gaps were observed by SEM. RESULTS: OCT could detect adhesive-dentin-bonded and adhesive-dentin-debonded gaps. SE-containing groups showed significantly lower GPS than FL-containing groups. FL-BFP showed significantly lower WLD than FL-ES. Microhardness of dentin wall lesions was higher than that of outer lesions and they showed significant differences in FL-BFP. SE-BFP showed a lower GPS curve and higher intensities of Ca and P in the upper half of dentin wall lesions than other groups. From SEM, microgaps between filler and matrix, break and loss of matrix, separation of adhesive matrix with hybrid layer occurred at interfacial gaps. SIGNIFICANCE: The morphological, mechanical and chemical characteristics of resin-dentin interfacial degradation depend on the component and chemistry of restorative materials.

Periodontal health related-inflammatory and metabolic profiles of patients with end-stage renal disease: potential strategy for predictive, preventive, and personalized medicine.

OBJECTIVES: To compare the periodontal health related-inflammatory and metabolic differences between patients with end-stage renal disease (ESRD) and healthy controls (HC), and to identify potential biomarkers in gingival crevicular fluid (GCF) and serum of ESRD patients for predictive, preventive, and personalized medicine (PPPM). METHODS: Patients with ESRD (ESRD group; n = 52) and healthy controls (HC group; n = 44) were recruited. Clinical periodontal parameters were recorded. The differential metabolites in the GCF and serum were identified by liquid chromatography/mass spectrometry (LC/MS). Inflammatory markers including interleukin-1ß (IL-1ß), interleukin-6 (IL-6), interleukin-8 (IL-8), and C-reactive protein (CRP) were also assessed. RESULTS: In the ESRD group, IL-8 and CRP were significantly higher in GCF, whereas IL-6 and CRP were significantly higher in serum, compared with HC group (all P < 0.05). In the case of GCF, taurine levels were positively correlated with IL-8 levels in both groups (all P < 0.05). In the case of serum, l-phenylalanine and p-hydroxyphenylacetic acid levels were positively correlated with CRP levels in both groups (all P < 0.05). Significant positive correlations were observed between metabolites (including pseudouridine, l-phenylalanine, and p-hydroxyphenylacetic acid) and IL-6 levels only in ESRD group. CONCLUSIONS: IL-8 and CRP are potential inflammatory makers that reflect the periodontal health of ESRD individual, which may be considered the valuable predictive diagnostics in the agreement with PPPM philosophy. Besides, metabolites of taurine in GCF as well as l-phenylalanine and p-hydroxyphenylacetic acid in serum are possible biomarkers correlated with inflammatory markers. All these biomarkers may also be highly recommended as a novel predictive/diagnostic tool for the assessment of inflammatory status from the perspectives of PPPM in view of susceptible population and individual screening.