Relationship Between Primary Molars Caries Or Permanent Teeth Eruption And Body Mass Index Among 7-8 Year-old School Children In Guangzhou Baiyun District Suburban Areas

ObjectivesTo investigate and discuss the correlation between the primary molars caries or permanent teeth eruption and body mass index(BMI)by surveying the prevalence of primary molars caries and status of the permanent teeth eruption and measuring and screening the rate of underweight,overweight,obesity of primary school kids aged 7-8 in baiyun district suburban areas,Guangzhou.Research on the related factors of primary molars caries and overweight or obesity via questionnaire.Materials and Methods1.Research subject:Adopting the methods of cluster sampling and systematic sampling,2032 students(male:1136;female:896)aged 7-8 from 19 primary schools in Baiyun district suburban areas,Guangzhou were recruited for further analysis after excluding invalid samples based on basic information and survey results.2.QuestionnaireThe content of the questionnaire is well-designed on the basis of the objective of this research,which includes the possible relative factors of children dental caries and their growth&development.The main references include the third and the forth national epidemiology survey of oral heath.This questionnaire can be divided into five categories:1)Basic information:name,gender,date of birth,classes and grades.2)Tooth brushing habits:frequency,method and time.3)Diet:Frequency of snacks intake during class breaks;frequency of carbohydrate and beverage intake,breakfast eating and bedtime dessert habits;4)Physical activity:frequency of aerobic and strenuous exercise;preference for PE classes.5)Others:Allowance;self-evaluation of body shape;history of tooth injury,truancy.etc.3.Oral examinationThe assessment of primary molar tooth decay was conducted rigorously under the criterion of International Caries detection and Assessment System ?,ICDAS-?.That is with a light source,visual and probing examinations were both involved.This results were compared and analyzed according to the different cut points:D1(Level o:healthy,Level 1-6:dental caries);D3(Level o-2:healthy,Level 3-6:dental caries);D4(Level o-3:healthy,Level 4-6:dental caries);D5(severe dental caries).The eruption of permanent tooth is marked by the broken of gingiva.4.Measurement of height and weightThe height and weight was measured by lever-type weighing machine and vertical height indicator respectively.The figures were taken for twice and the mean value is recorded with the accuracy of 0.1cm and 0.1kg respectively.The subjects were grouped as emaciation,normal,overweight and obesity in accordance with the diagnostic criteria of International Obesity Task,IOTF for children aged 2-18.ResultsThe condition of dental caries among 2032 children aged 7-8:the prevalence of D1:88.6%;dmft:4.42;D3:79.6%;dmft:3.46;D4:71.0%;dmft:2.78;D5:63.0%;dmft:2.36.Gender difference had no statistical significance(P>0.05).Eruption rate of permanent tooth:66.81%,mean value:10.72.The rates of underweight,overweight and obesity were 14.4%.12.1%and 5.1%respectively according to IOTF standard.With the rise of BMI index,the number of primary molar tooth caries declines,in contrast,the eruption rate increases.Correlation can be found between overweight/obesity and primary molar tooth decay and permanent tooth eruption rate by Logistic regression analysis.Through questionnaire,correlation can be found between primary molar tooth caries,tooth brushing habits and eating and appetite affected by oral diseases.More physical activity was needed in the overweight and obesity categories.ConclusionsThe prevalence of dental caries of children aged 7-8 in baiyun district suburban areas is higher than the average rate in Guangzhou.Therefore,further effective measures are required for dental caries prevention.Even though the rates of overweight and obesity are on the rising trajectory,they are slightly lower than the corresponding figures in some developed cities nationwide.Inversely,the thinness rate shows a downward trend.Primary molar tooth caries and permanent tooth eruption are highly relevant to children growth and development.Dental caries also exert negative effects on kids' eating and appetite.Additionally,kids with overweight or obesity demonstrate better sport performance,which may indicate healthier lifestyles.