Correlation Between Nitric Oxide And Periodontal Disease

[Objective]The objective of the study is analyzing the relationship between nitric oxide and periodontal disease by observing the expression of inducible nitric oxide synthase(iNOS) in periodontal tissue and detecting the level of nitric oxide in gingival crevicular fluid(GCF).[Methods](1) The first part of the study included 20 patients with activity of chronic periodontitis,20 patients with non-activity of chronic periodontitis and 20 periodontally healthy persons.Immunohistochemistry staining was performed for evaluating iNOS expression in periodontal tissue.All samples were fixed by 4% paraformaldehyde,and observed by microscope.(2) The second part of study included 22 gingivitis,32 chronic periodontitis patients and 20 periodontally healthy persons,of which gingivitis and chronic periodontitis patients were experienced initial periodontal therapy.Conventional clinical periodontal index of all subjects were recorded.The level of nitric oxide in gingival crevicular fluid was measured by immunofluorescence.[Results](1) iNOS expression was manily founded in epithelial cells and inflammatory cells in connective tissue.The expression of iNOS in control group was lower than that in active and non-active of chronic peridontitis group.The expression of iNOS in non-active group was lower than that in active group of chronic peridontitis group.(2) The nitric oxide in GCF was a significant difference in chronic periodontitis group than that in gingivitis group and control group(p＜0.01).The nitric oxide in GCF was a significant difference in gingivitis group than that in control group(p＜0.01) There was a significant difference of nitric oxide in GCF in gingivitis and periodontitis group before and after treatment.(p＜0.01)[Conclusion](1) iNOS expression was manily founded in epithelial cells and inflammatory cells in connective tissue of gingiva in chronic periodontitis.The patients with activity of chronic periodontitis had the highest expression in all groups (2)Nitric oxide existed in GCF of patients with active,non-active of chronic periodontitis and periodontally healthy persons(3)After initial periodontal therapy, The level of nitric oxide in GCF decreased in gingivitis and chronic periodontitis (4)Nitric oxide was taken important role in the development of chronic periodontal disease.The iNOS expression in gingival tissue and the level of nitric oxide in GCF had close relation with degree of inflammation.