Dental Disease Epidemical Study On Dongxiang,Bao-an,Yugu Nationalities Of China

To find out the status of oral epidemiology of the three special nationalities peculiarly resided in Gansu province--Dongxiang,Bao-an,and Yugu.We conducted an epidemiologic study of dental disease on dental caries and periodontal diseases and conducted an oral knowledge questionnaire to two age groups among these three nationalities.Through our investigation,we wanted to know the oral health state and influencing factors of different groups among these three nationalities in Gansu Province,P.R.China,monitoring the prevalence trendency of dental caries and periodontal diseases,to understand their basic knowledge level on dental,their attitude to and behavior of oral hygiene and their utilizing condition of oral health care,io order to provide some information to support for the evaluation and monitoring the execution of"china oral Health care planning"(2004-2010)in ethnic race regions.Find out the status quo of oral microorganism of the three special nationalities peculiar to Gansu province,carried out three national epidemiological survey of oral micro-organisms and study the relevance of the oral streptococcus mutans and microorganism of the three ethnic groups to children's dental caries.Through the molecular epidemiology research on dental caries of Dongxiang and Bao-an nationalities,study the relevance of VDRTaq1 polymorphism to prevalenc e risk of dental caries of the groups from Dongxiang and Bao-an nationalities in Gansu province.Through the test and analysis of the above-mentioned gene polymorphism,explore the relevance of the distributing frequency of various genotypes in these genes to the prevalence risk of dental caries.Look forward to finding out the genetic causes of the prevelance of dental caries of Dongxiang,Bao-an groups from the molecular biology level of genes.We can use the relative genotypes with susceptibility that have been founded as the detection indicators of dental caries susceptibility,so as to find out and identify the Vulnerable groups with dental caries.To improve with a clear aim the early warning to the corresponding groups and take positive measures against dental caries.Specific results are as follows:The representative samples were selected by cluster sampling methodology from the all 1604 persons,which were divided into four age groups,5,12,35～44,65～74 years,including 55 male and female in each group.Sampling survey proposal and technology were based on the Third National Wide Oral Health epidemiological survey.And we used the questionnaire of the Third National Wide Oral Health epidemiologieal survey questionnaire of oral health at 5,12 group.There are 301 children investigaed at the age of 5 group,299 parents and 448 children investigated for the age group of 12,for questionnaire.Conduct an investigation of oral microbial epidemiology on 5-year-old children and 12-year-old ones of Dongxiang,Bao-an and Yugu nationalities.Make a random sampling of a total of 100,5-year-old children from Dongxiang and Yugu nationalities respectively,with 50 from each.Make a random sampling of 165,12-year-old children in all from the three nationalities,with 50 from Dongxiang nationality,55 from Bao-an nationality and 60 from Yugu nationality.The streptococcus mutans will be tested by the kit produced by Orion Diagnostm company in Finland.Choose 264 patients with dental caries from Dongxiang and Bao-an nationalities in Linxia,Gansu province and a total of 219 persons without systemic disease as the control group,so as to conduct a study on gene suscepbility of dental caries.The DNA was extracted from EDTA anticoagulant peripheral blood by using standard method of proteinase K and phenol-chloroform organic extraction.1.1 The results of dental caries1.1.1 Age 5 group There was a statistical difference between the results of Dongxiang and Bao-an(x~2=9.5403,P=0.002);but there was no statistical difference between Dongxiang and Yugu(x~2=2.6799,P=0.1016),Bao-an and Yugu(x~2=2.9812,P=0.0842).The caries prevalence of Dongxiang and Bao-an is higher than that of the whole nation and the western part of China and also has statistical difference with them.The results of Yugu are higher than that of the whole nation and the western part of China,but there was no statistical difference.(Restrict at length of writing,we only describe the sex differences and comparison with the whole nation and the western part of China in results,same as below)1.1.2 Age 12 group There was no statistic difference between Dongxiang and Bao-an(x~2=2.2997,P=0.1294),Dongxing and Yugu(x~2=2.1817,P=0.1397) but there was a statistical difference between the results of Bao-an and Yugu (x~2=8.7403,P=0.0031).1.1.3 Age 35～-44 groupPrevalence of crown caries There was statistical difference among the three nationalities(x~2=32.083,P=0.000).Prevalence of root caries There was a statistical difference between Dongxing and Bao-an(x~2=28.499,P=0.004),also between Bao-an and Yugu (x~2=21.5451,P=0.000),but there was no statistical difference between Dongxing and Yugu(x~2=0.5710,P=0.4499).1.1.4 Age 65～74 groupPrevalence of crown caries There was no statistical difference among these three nationalities(x~2=5.926,P=0.052).Prevalence of root caries There was a statistical difference between the results of Dongxiang and Bao-an(x~2=10.7434,P=0.001),but there was no statistical difference between Dongxiang and Yugu(x~2=1.9428,P=0.1634),Bao-an and Yugu (x~2=3.1963,P=0.0738).1.2 The results of periodontal diseases1.2.1 Age 12 groupGingival hemorrhage There was no statistical difference beteen the results of Dongxing and Bao-an(x~2=0.4206,P=0.0516),but there was a statistical difference between Dongxiang and Yugu(x~2=94.1576,P=0.000),Bao-an and Yugu (x~2=80.4166,P=0.000).Calulus There was no statistical difference among the three nationalities.1.2.2 Age 35～44 groupGingival hemorrhage There was no statistical difference between the results of Dongxiang and Bao-an(x~2=0.7309,P=0.3902),but there was a statistical difference between Dongxiang and Yugu(x~2= 18.0775,P=0.000).Bao-an and Yugu(x~2=25.7951,P=0.000).Calculus There was no statistical difference among the three nationalities (x~2=1.032,P=0.597).Periodontal pocket There was no statistical difference between the results of Dongxiang and Bao-an(x~2=0.0684,P=0.7936),but there was a statistical difference between Dongxiang and Yugu(x~2=19.1641,P=0.000),Bao-an and Yugu (x~2=17.3956,P=0.000).1.2.3 Age 65～74 groupGingival hemorrhage There was a statistical difference between the results of Dongxiang and Bao-an(x~2=5.1868,P=0.0228),Dongxiang and Yugu(x~2=20.7198,P=0.000),Bao-an and Yugu(x~2=8.8395,P=0.0029).Calculus There are no statistical difference among the three nationalities(x~2=1.656,P=0.437).Periodontal pocket There was a statistical difference between the results of Dongxiang and Bao-an(x~2=7.272,P=0.007),Dongxiang and Yugu(x~2=12.066,P=0.001), but there was no statistical difference between the results of Bao-an and Yugu(x~2=1.303,P=0.253).2.The differences of the levels of streptococcus mutans in saliva of children at 5 and 12 between the nationalities are of statistical significance.The differences of the levels of streptococcus mutans in dental plaque at different tooth positions of the age 12 group among the three nationalities are of statistical significance.Among the 5-year-old children of the two nationalities,the proportion of cocci in dental caries are significantly higher than those in the normal teeth,while the proportion of bacilli are all significantly lower than those in the normal teeth.Among the 12-year-old children of the hree nationalities,proportion of cocci are significantly higher than those in the normal teeth,while the proportion of bacilli are all significantly lower than those in the normal teeth.With the increase of the level of streptococcus mutans in the oral cavities of age 5 group,the prevalence rate of caries of dedicuous teeth shows an upward trend.It doesn't indicate that the level of oral streptococcus mutans of age 12 group is positively relevant to the degree of dental caries.In dental plaque of caries,basically the ratio of cocci is increasing,while that of bacilli is decreasing.The reason for this change may be related to the succession process of oral microorganisms.3.As for VRDTaq1 locus polymorphism,the prevelance risk of dental caries for individuals with genotype Tt is increasing and allele t is the suscepbility gene of dental caries.VRDTaq1 locus polymorphism is not relevant to the sex of patients with dental caries.The differences of distributing frequency of VRDTaq1 polymorphism among the groups from Dongxiang,Bao-an and Han have no statistical significance.The molecular epidemiology research on dental caries in two nationalities provides the basic data of the distribution and classification of caries-related suscepbility genes;Lays a foundation for the further longitudinal study of the dynamic changes of the relationship between suscepbility gene and dental caries of the groups;Provides certain theoretical basis for the molecular typing,diagnosis and gene therapy of dental caries.Among the three Nationalities,except some groups of Yugu nationality,there exists statistical difference on prevalence of dental disease when comparing to the whole nation and the western part of china.On these three nationalities,the government of China needs to strengthen education about oral health awareness,to improve the situation of human power and financial resources in order to reach the goal of the national oral health.Through the investigation of oral health epidemiology for the three special nationalities,we find out that part of the indicators of some age groups show that the knowledge of oral hygiene and idea are not relevant to the results of the prevalence rate,for which we cannot explain the reason,therefore it cannot be excluded that the ethnic factor is one of the most important attributes to such results.Oral health indicator has no much difference in childhood,which suggests that the risk factor is almost similar to childhood,but different from adult groups for the reason of difference of dental hygiene conception,deficiency of medical personnel,insufficiency of medical treatment facilities and racial difference.The training work on dentists is quite unparallel to the existing national strength,development and level of ecomomy.Therefore we must intensify the training for doctors and significantly increase the budget imput on stomatology education.