The Cariogenic Microorganisms Analysis In Root Surface Plaque Of Treated And Untreated Patients With Periodontitis

Background:It is crucial important that the root surface caries is one of the intercurrent syndromes of the chronic periodontitis patients who had basic periodontal treatment. The cariogenic microorganisms of the exposed root surface had difference between the treated and untreated patients. The changes causing the root caries remains unclear. Studies on the microbiology of the root surface caries show that there are different theories on the pathogen of root surface caries. Some scholars regarded the relative pathogen as Actinomyces viscosus ;Others had suggested that the main pathogen was Streptococcus mustans;and still other scholars regarded as lactobacillus. But the pathogenic bacteria of the root surface caries is not well defined yet.Objective:1. The aims of this present study are to investigate whether the cariogenic microorganisms of the exposed root surface are different between the treated and untreated patients comparing to the pathogenic bacteria of the root surface caries ; to filtration the main pathogenic bacteria; to investigate the susceptibility of the root surface caries of the chronic periodontitis patients who had exposed root surface .2. The aim of this present study is to investigate the effections of Streptococcus mustans and Actinomyces viscosus in the development of root surface caries.Methods:In this study ,40 patients were selected from Henan Stomatological hospital .The test group included 20 chronic periodontitis patients who had exposed root surface. The control group consisted of 20 patients who had root surface caries. Each patient gave informed consent for dental examination .The patients of the test group were taken standardized samples of supragingival plaque from the exposed root surfaces based on their stage of periodontal treatment. It was divided into 5 groups :1.the time before basic periodontal treatment, 2. the time after a week of basic periodontal treatment, 3. the time after a month of basic periodontal treatment, 4.the time after two months of basic periodontal treatment, 5. the time after three months of basic periodontal treatment. The patients of the control group were taken standardized samples of dental plaque from root surface caries lesions .The samples were diluted and respectively inoculated to the selective medium including MSB.CFAT and GAM by anaerobic cultures. The colony's CFU/ml was recorded. Applying SPSS FOR WINDOWS 13.0 to analyze the data, using analysis of variance (ANOVA)and Independent Samples Test . Statistically significant level is considered as "alpha equals 0.05".Results:1. Streptococcus mustans and Actinomyces viscosus were isolated from the teset group and the control group .2. Streptococcus mustans from the test group were changed. Comparing to the group of before basic periodontal treatment, the groups of a week, two months and three months had significant difference (P<0.05). Comparing to the group of one week and one month had no significant difference(P>0.05).3. Actinomyces viscosus from the test group were changed. Comparing to the group of before basic periodontal treatment ,the group of one month, two months and three months had significant difference (P<0.05). Comparing to the groups of one week and one month before basic periodontal treatment and a week , the groups of one month and two months, one month and three month ,two months and three months had no significant difference(P>0.05).4. Streptococcus mustans was analyzed between the test group and the control group. Comparing to the group of before basic periodontal treatment ,the groups of one month and three months to the control group had significant difference (P<0.05). Comparing to the groups of one week and two months to the control group had no significant difference(P>0.05).5. Actinomyces viscosus was analyzed between the test group and the control group. Comparing to the group of before basic periodontal treatment , the groups of one week, two months and three months to the control group had significant difference (P<0.05). Comparing to the groups of one month to the control group had no significant difference(P>0.05.6. Streptococcus mustans and Actinomyces viscosus from the control group had significant difference (P<0.05).Conclusion:1 .The results of this study showed that the cariogenic microorganisms have changed in root surface plaque of treated and untreated periodontitis patients. Streptococcus mustans in root surface plaque of treated and untreated periodontitis patients had changed .The changes improved firstly,then decreased, keeping on a stabilized level finally . Actinomyces viscosus in root surface plaque of treated and untreated periodontitis patients had improved.2. Actinomyces viscosus is the main pathogen of root surface caries in the elder people.3. It is important that taking a series of measures to prevent the development of the root surface caries to the periodontists patients with exposed root surface in the three months.