Study Of Biological Character Of Periodontal Ligament Cells In Elderly People And Pathologic Changes Of Periodontitis Of Elderly Peoples

The periodontitis in elderly peoples and injure is increasing with aging , moreover it is far higher in elderly people than in other peoples.Generally it is thought these are related to the changes of ability of anti-infection and repairment of tissues , function immunology , ability of anti-oxidation , level of NO and apoptsis. According to those theories , we design a series of pexperiments to study on biological character of periodontal ligament cells in elderly people and pathologic changes of periodontitis of elderly peoples with methods of immunohistochenical , MTT and spectrphotometry. We can get conclusions as:1 Growth of elderly healthy donors periodontal ligament cells were much slower than that of young healthy donors ; proliferation(As7o) of elderly healthy donors periodontal ligament cells were considerably lower than that of young healthy donors on 1 ,3 , 5, 7, 9 day (P<0.01) . Conclusions: Under the influence of ageing , proliferation ability of elderly peoples periodontal ligament cells was significantly decreased and was significantly different from that of young peoples. These showed that ageing might be one of important reasons which result in decreasing in repairing and proliferation ability of elderly peoples periodontal tissues.2 Elderly peoples PDL cells exhibited significantly lower alkalinephosphatase activity than the young peoples PDL cells ( P<0.01). Their ability to respond to fetal calf serum ( PCS ) was also lower than that of young peoples PDL cells ( P<0.01 ). Conclusion: These results suggest that ability to form mineralized tissue in elderly peoples PDL cells may be altered , functions affecting the maintenance and regeneration of the periodontium .3 The expression of Fas-antigen in periodontal ligament cells of elderly peoples was obviously heavier than that in periodontal ligament cells of young peoples . The expression of iNOS in periodontal ligament cells of elderly peoples was positive, but the expression of iNOS in periodontal ligament cells of young peoples was negative. Conclusions: The decrease of proliferation of periodontal ligament cells of elderly peoples was relative to increasing of sensitivity to apoptosis in periodontal ligament cells of elderly peoples.4 Chemotaxis and phagocytosis of neutrophil leukocytes in elderly patients with periodontitis were much lower than those in adult and juvenile patients with periodontitis(P < 0.05 , P < 0.01). Conclusion : Defect of host defense may be one of the major factors causing periodontitis in elderly patients.5 The activity of NK cells of venous blood in elderly patients with periodontitis was significantly lower than that in adult patients (P < 0.01) and juvenile patients (P < 0.05 ) with perodontitis. Conclusion: These data suggested that the low activity of NK cells of venous blood in elderly patients with periodontitis may be one of the major factors causing serious periodontitis in elderly patients with periodontitis.6 The incidence ol NK ceils positive cases in gingiva in elderly patients with periodontitis was less then the incidence of adult patients.The number of positive NK cells was less than the number of positive in adult patients. Conclusion: These results suggest that the functions NK cells in gingiva may be low in elderly patients with periodontitis.7 In elderly patients with periodontitis, the cases of IgM positive cells in gingiva (15 cases) were more than those of IgA positive cells(4cases), which was contrary to the adult patients with periodontitis.the number of CD4+ and CDs" lymphocytes in gingiva in adult patients with periodontitis was much greater than that in elderly patients (P <0.05). Conclusion: Elderly patients with periodontitis have certain specific characteristics in immunohistochemitry , such as low immunological function in local gingival and poor function of immunological regulation.8 Level of SOD in eldly patients group was significantly lower than those in health elder group, adult patients group and j...