The Study Of The Relationship Between The Gingiv Health And Porphyromonas Gingivalis And Its Virulence Factor Fimbriae Protein During Orthodo Ntic Treatment

Objective: All the time, in the progress of orthodontic treatment, the gingival condition of most patients is bad.There are many elements. The first of them is the dysbacteriosis. There is closely relationship between Porphyromonas gingivalis and periodontal disease. But there are rarely reports about the relationship with FimA which is one of the virulence factors of Porphyromonas gingivalis and gingivitis inflammation in the course of orthodontic treatment At the same time, in the process of orthodontic, the distribution change of six genotypes of FimA also rarely has been reported. This study would applied 16SrDNA PCR skill to detect 61 orthodontics treatment patients’Porphyromonas gingivalis and six genotypes of FimA in gingival crevicular fluid (GCF), and then to analyse the impact of them in the progress of orthodontic gingivitis happening. The results of this study would be the experiment foundation for the following researches.Methods: we establish 16SrDNA PCR technique to check out Porphyromonas gingivalis and six genotypes of FimA. And then make use of Porphyromonas gingivalis to detect sensitivity and specificity of the PCR technique. Totally 61 patients randomly chosen from orthodontic department of Jinan Stomatological Hospital, were collected the gingival crevicular fluid at prior orthodontic treatment, the first month, the second month, the third month and the sixth month separately ,and record the gingivitis index for one-to-one correspondence. Finally, after test the composition of the specimens, using SPSS 20.0 software to statistical analysis, detection rate comparison between each group with Chi-square text. The relationship between six genotypes of FimA and the gingival inflammation index with Spearman rank correlation analysis.Results: Chi-square text shows, Pg and genotype Ⅳ between prior treatment and the third month have extremely significant difference (P < 0.01). Genotype II and V between prior treatments and the third month have significant difference (P < 0.05). Genotype I, III and I b have no statistical significance. Spearman rank correlation analysis shows, the detected number of all the kinds have obvious growth trend in first trimester of treatment, and the highest number appeared at the third month. And then gradually decreased, some detected number indeed returned to the prior treatments state. There are obvious positive correlation with gingival index and Pg , genotype I and genotypeⅤ. They have extremely significant difference (P<0.01). There also have obvious positive correlation with gingival index, and genotype Ⅱ and genotype Ⅰ b. They have significant difference(P<0.05). Genotype Ⅲ and genotype Ⅳ had no statistical significance. Conclusion: 1.When the adolescent treated by fixed appliance, the fixed appliance increased the difficulty of oral cleaning and destroyed the normal micro ecological balance of oral. And then gingiva is inflamed. Finally, it caused periodontal tissue lesions. 2. The six genotypes of FimA have vary widely in their degrees of change and the relevancy with periodontal health in the course of orthodontic treatment.This phenomenon shows that the toxicity and pathogenicity of the six genotypes of FimA is different.3. The change of genotype Ⅳ is most obvious in different periods of time, at the same time, there has closely correlation between gingival inflammation index and genotype Ⅳ,so, the genotype Ⅳ plays a more important role in the gingival health during orthodontic treatment.