Prevalence and influencing factors of malocclusion in adolescents in Shanghai, China.

BACKGROUND: The main purpose of the study was to investigate the prevalence and related risk factors of malocclusion in permanent dentition among adolescents in Shanghai, and provide basic data for government's preventive strategies and intervention plans. METHODS: 1799 adolescents aged 11-15 years old from 18 middle schools in 6 districts of Shanghai were recruited to investigate oral health status and related risk factors using cluster random sampling method in 2021. Malocclusion and caries were examined by on-site inspection. The investigation criteria referred to Bjoerk and the recommendation of the WHO. The malocclusion inspection items included molars relationship, canine relationship, overbite, overjet, midline displacement, anterior crossbite, posterior crossbite, scissors bite, crowding and spacing. The subjects were asked to fill in a questionnaire including parents' education level, oral health behaviors and dietary habits. The chi-square test and logistic regression analysis were used to analyze the relationship between malocclusion and risk factors. RESULTS: 1799 adolescents were included in the study and the prevalence of malocclusion in adolescents in Shanghai was 83.5%, and the proportion of molar relationship class I, class II, and class III was 48.9%, 14.7%, and 19.0%, respectively. The most common occlusal characteristic of malocclusion was anterior crowding, followed by midline irregularities and deep overbite, with prevalence rates of 44.8%, 39.0% and 38.6%, respectively. The prevalence rate of adolescents with caries was 34.3%. Those who had dental caries and preferred soft food were more likely to have abnormal occlusal characteristics (p < 0.05). CONCLUSION: The prevalence of malocclusion in adolescents in Shanghai is high, so it is of great significance to strengthen oral health education, allocate proper preventive strategies and carry out the early correction if necessary.

Association between occlusal support and cognitive impairment in older Chinese adults: a community-based study.

Introduction: The loss of occlusal support due to tooth loss is associated with systemic diseases. However, there was little about the association between occlusal support and cognitive impairment. The cross-sectional study aimed to investigate their association. Methods: Cognitive function was assessed and diagnosed in 1,225 community-dwelling adults aged 60 years or older in Jing'an District, Shanghai. Participants were diagnosed with mild cognitive impairment (MCI) by Peterson's criteria, or dementia, according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition. We determined the number of functional occlusal supporting areas according to Eichner classifications. We used multivariate logistic regression models to analyze the relationship between occlusal support and cognitive impairment and mediation effect models to analyze the mediation effect of age. Results: Six hundred sixty participants were diagnosed with cognitive impairment, averaging 79.92 years old. After adjusting age, sex, education level, cigarette smoking, alcohol drinking, cardiovascular disease, and diabetes, individuals with poor occlusal support had an OR of 3.674 (95%CI 1.141-11.829) for cognitive impairment compared to those with good occlusal support. Age mediated 66.53% of the association between the number of functional occlusal supporting areas and cognitive impairment. Discussion: In this study, cognitive impairment was significantly associated with the number of missing teeth, functional occlusal areas, and Eichner classifications with older community residents. Occlusal support should be a significant concern for people with cognitive impairment.

Oral microbiome in older adults with mild cognitive impairment.

The association between the oral microbiome and mild cognitive impairment (MCI) remains unclear. This study aimed to investigate such an association among Chinese older adults. Participants without dementia were recruited from the community. A battery of neuropsychological tests was administered to evaluate the cognitive function. The diagnosis of MCI was based on Peterson's criteria. The non-stimulated saliva was collected to extract sequences of the oral microbiome. Forty-seven MCI and 47 cognitively normal participants were included. There was significant difference in alpha diversity and insignificant difference in beta diversity between the two groups of participants. Compared with the cognitively normal group, Gemella haemolysans and Streptococcus gordonii were two significantly decreased species while Veillonella unclassified_Veillonella and Fusobacterium sp._HMT_203 were two significantly increased species in the MCI group. The richness of Gemella haemolysans presented the best discriminate value for MCI with the AUC (Area Under Curve) of 0.707, a cut-off value of 0.008 for relative abundance, the sensitivity of 63.8% and specificity of 70.2%. The dysbiosis of oral microbiome and relative abundance of Gemella haemolysans was significantly associated with MCI. Further studies were needed to develop new treatment strategies targeting the oral microbiome for cognitive impairment.

Excessive fluoride impairs autophagy flux in ameloblasts which is prevented by the autophagy activator rapamycin.

Excessive fluoride intake can cause dental fluorosis during teeth development and growth. However, the mechanisms underlying fluoride-induced enamel damage are still not fully elucidated. Previously, we observed fluoride-induced autophagy in ameloblasts, but the effects of fluoride on autophagy flux in ameloblasts remain unclear. Hence, this study aimed to clarify the effects of fluoride and rapamycin, an autophagy activator, on autophagy flux in ameloblasts. This in vitro study used the murine ameloblast-derived cell line LS8. Cells were treated with different concentrations of sodium fluoride (NaF) to evaluate NaF-induced cytotoxicity. Using transmission electron microscopy, we observed an increase in the number of autophagosomes with increasing fluoride concentrations. Western blot analyses showed increases in microtubule-associated protein 1 light chain 3 (LC3) and SQSTM1 (p62) expression after NaF treatment and an increase in LC3II expression after bafilomycin A1 administration. Together with changes in RFP-GFP-LC3 lentivirus expression, this demonstrated that fluoride impaired autophagy flux. Furthermore, we evaluated whether rapamycin can alleviate fluoride-induced cytotoxicity by restoring autophagy flux. Compared to the NaF-treated group, LS8 cells cotreated with NaF and rapamycin grew considerably better and had significantly decreased p62 expression. Taken together, these data suggest that fluoride-induced impaired autophagosome degradation may damage ameloblasts. This provides experimental in vitro evidence and an explanation for the observed NaF-induced toxicity of ameloblasts. Rapamycin probably alleviates this impairment by decreasing the expression of p62, thereby preventing autophagy defects.

The Association of Tonsil Hypertrophy with Pediatric Dentofacial Development: Evidence from a Cross-Sectional Study of Young Children in Shanghai, China.

Purpose: The prevalence of dentofacial deformity was reportedly higher than decades ago, to which upper airway (UA) obstruction-induced sleep-disordered breathing (SDB) might contribute a lot. Tonsil hypertrophy appears relatively common in the population of young children. Given that the association between tonsil hypertrophy and pediatric dentofacial deformity remained controversial, this cross-sectional research was designed to explore the internal relationship of those among young children in Shanghai, China. Patients and Methods: A stratified cluster sampling procedure was adopted, and a representative sample of 715 young children (8-10 years old) was recruited. The OSA-18 quality-of-life questionnaires (OSA-18) were finished by their guardians, and well-trained orthodontists performed the oral examinations. After collecting the valuable information, the descriptions and analyses were run by statistical software (SPSS, version 26.0). Results: 715 participants (334 boys and 381 girls) were involved in the analyses. As calculated, the current prevalence of malocclusion identified by Angle's classification was 45.6% in this sample. No evident relation between OSA-18 scores and dentofacial abnormalities (P > 0.05) was found. With the enlargement of tonsil size, the proportion of children with triangular dental arch form (P < 0.05) and high vault palate (P < 0.001) was increasingly higher. More children with protruding profiles and fewer upright profiles were observed as the tonsil size increased, although it did not show a statistical difference (P = 0.103). Conclusion: Dental and craniofacial growth deficiency has become more prevalent among children, demanding more concerns from health authorities. Tonsil hypertrophy plays an essential role in the direction of dentofacial development. More efforts from local health authorities should be made to enhance public propaganda and education on the prevention and interruption of tonsil hypertrophy and related dentofacial abnormalities.

Association of occlusal support with type 2 diabetes: A community-based study.

Occlusal support was proved to be associated with type 2 diabetes. Our aim was to investigate the association between the Eichner index and the prevalence of type 2 diabetes. We included 715 participants with oral health examinations in the Shanghai Aging Study. The occlusal support status was determined by the number of functional occlusal support areas and Eichner index classifications. Those with fasting plasma glucose ≥126 mg/dL and/or hemoglobin A1c ≥6.5% and/or current medications for type 2 diabetes with relevant medical history were diagnosed with type 2 diabetes. Multiple logistic regression models were used to analyze the relationship between occlusal support status and type 2 diabetes. The average age of 715 participants was 73.74 ± 6.49 years old. There were 84 diabetics with 1.71 occlusal supporting areas on average. Seven hundred and fifteen participants were divided into 3 groups according to Eichner classifications: Eichner group A with 4 occlusal functional areas, Eichner group B with 1-3 occlusal functional areas or 0 area with anterior occlusal contact, and Eichner group C with no functional occlusal contact. Blood glucose level was significantly lower in participants of Eichner group A compared to those in group B or C. The ordinal logistic regression showed more occlusal supporting areas were significantly associated with less type 2 diabetes cases with an Odds Ratio(OR) of 0.253(95%CI 0.108-0.594) after adjusting covariates. Participants in Eichner group A had a significantly much lower OR of 0.078 for type 2 diabetes (95%CI 0.009-0.694) compared to those in Eichner group C after adjustment. The number of functional occlusal support areas might be inversely related to the blood glucose level and the prevalence of type 2 diabetes.

miR-296-5p promotes autophagy in mouse LS8 cells under excessive fluoride via AMPK/ULK1 pathways.

Numerous microRNAs participate in regulating the pathological process of autophagy. We have found miR-296-5p is one of the most significantly down-regulated microRNAs in a high concentration of sodium fluoride. However, it is not clear whether miR-296-5p augments autophagy in dental fluorosis. Our purpose is to explore the function of miR-296-5p in regulating autophagy of excessive fluoride development. Thus, the cell line of ameloblasts LS8 was exposed to a 1.5 mM dose of NaF and miR-296-5p-mimics, Real-time qPCR, CCK-8 assays, Fluorescence imaging and Western blot analysis were performed. Autophagy was observed. As our results indicated, miR-296-5p overexpression in mouse LS8 cells significantly accelerated autophagy. The autophagy inhibition effect of miR-296-5p underexpression was consistent with the effect of the AMPK inhibitor. And we found that the expression of LC3II was decreased via down-regulation of AMPK. The change of ULK1 by miR-296-5p may be accomplished through AMPK. Thus, miR-296-5p may improve the secretion of autophagic mediators by activating AMPK/ULK1 expression in fluorosis, suggesting that miR-296-5p, AMPK/ULK1 may be potential therapeutic targets under the higher fluoride stimulation.

Association between tooth loss and hypertension among older Chinese adults: a community-based study.

BACKGROUND: The purpose of the study is to examine the association between tooth loss and hypertension among older community residents in urban China. METHODS: This study included 3677 participants aged ≥50 years from the Shanghai Aging Study. We determined the number of teeth missing from questionnaires. Hypertension was defined as the mean of two measurements of systolic blood pressure (SBP) (140 mmHg or higher), diastolic blood pressure (DBP) (90 mmHg or higher) or physician-diagnosed hypertension confirmed from medical records. A multivariable logistic regression model was used to investigate the association between tooth loss and hypertension. RESULTS: The average number of missing teeth among study participants was 9.67. Among them, participants with hypertension had lost an average of 10.88 teeth, significantly higher than those without hypertension (8.95) (p < 0.0001). After adjusting for covariates (socio-demographic characteristics, health behaviors and other chronic conditions), teeth lost (15 or more) was significantly associated with grade III hypertension, with OR = 1.55(95% CI 1.09-2.20). CONCLUSIONS: Significant tooth loss maybe associated with severe hypertension among older Chinese adults. Prevention of tooth loss is important to the overall health of this population.

[Clustering analysis in the pattern of KAP model on the application of oral health among students aged 12-15 in Shanghai].

PURPOSE: To assess the relation of oral health knowledge, attitude and practice(KAP) of the students aged 12-15 in Shanghai, and provide data support for intervention strategies of oral health. METHODS: A total of 2927 subjects aged 12-15 years old were selected according to the method of the Fourth National Oral Health Epidemiological Survey and the questionnaire was filled. SAS 9.4 software package was used for statistical analysis. RESULTS: The subjects were divided into 2 categories according to their knowledge and attitude of oral prevention and oral health. TypeⅠgroup, with high cognitive attitude, had more teeth brushing times than those of typeⅡgroup with poor cognitive attitudes(P<0.01). TypeⅠgroup had more people knowing and using toothpaste with fluoride. (P<0.01). The frequency of type I group using dental floss was significantly higher than typeⅡgroup(P<0.01), while the frequency of having deserts was relatively lower than typeⅡgroup (P<0.01), and the frequency of having drinks was lower than type Ⅱ(P<0.01). The two groups had no significant difference in the frequency of consumption of other drinks with sugar ( P=0.11). CONCLUSIONS: Oral related risk behaviors are quite common among 12-15 years students in Shanghai, which are closely related to the knowledge and attitude.