The comprehensive studies for establishment of a system to prevent periodontitis in adolescent students

为建立青少年学生牙周炎防治体系，本研究进行了为期3年(2001-2003年)的调查，取得了以下结果：1.青少年学生牙周炎的预防。本研究项目中的流行病学研究表明，青少年学生的牙周状况随着年龄的增长而恶化。在学校口腔健康检查中对牙周炎高发区学生进行筛查，可能有助于改善这些学生的牙周状况。提示牙龈假单胞菌、福赛斯双歧杆菌、直肠杆菌、伴生放线菌和中间假单胞菌可作为青少年学生牙周炎发病的危险标志物。检测这些牙周特异性病原菌和检测这些细菌的抗体效价均可作为牙周炎学生的筛查方法。在日本，IL-1受体拮抗剂基因串联重复序列(VNTR)和维生素D受体(VDR)/FcRIIIb基因组合与全身性EOP相关。此外，FcγRIIb基因多态性与慢性牙周炎的易感性相关。40 kDa外膜蛋白(40k-OMP)和200 kDa牙周炎抗原蛋白的免疫反应区(IVTVPENGK)被认为是一种潜在的牙周炎成分疫苗。此外，40k-OMP可作为预防牙周炎的鼻用疫苗。另一方面，新构建的针对130 kDa血凝素结构域的抗体可能被证明对牙周炎被动免疫的发展有用。阐明了伴生放线菌的毒力因子(细胞毒性膨胀毒素和荚膜多糖)及其对伴生放线菌感染的保护机制。对在校青少年学生进行口腔健康检查，积累牙周状况资料。

To establish a system to prevent periodontitis in adolescent students, we investigated for 3 years (2001-2003) in this research project, and the following results were obtained.1. Epidemiological studies in this research project demonstrated that periodontal conditions worsened with increased age in adolescent students.2. It was possible that the screening for students with high risk sites of periodontitis in school dental health examination contributed to the subsequent improvement of periodontal conditions in those students.3. It was clarified that P.gingivalis, B.forsythus, C.rectus, A.actinomycetemcomitans and P.intermedia might be able to be use as risk markers for onset of periodontitis in adolescent students.4. Both of detection of these specific periodontal pathogens and measuring IgG antibody titer against these bacteria might be useful for screening method for students with periodontitis.5. In Japanese, tandem repeat (VNTR) polymorphisms in IL-1 receptor antagonist gene and vitamin D receptor (VDR)/FcRIIIb genotype combination were associated with generalized EOP. Further, FcγRIIb gene polymorphisms associated with susceptibility of chronic periodontitis.6. The immunoreactive domain (IVTVPENGK) in 40-kDa outer membrane protein (40k-OMP) and 200-kDa antigenic protein from P.gingivalis were thought to have a potential use in a component vaccine against periodontitis. Further, 40k-OMP might be useful as a nasal vaccine for prevention of periodontitis. On the other hand, a newly constructed antibody against 130-kDa hemagglutinin domain may prove to be useful for development of passive immunization against periodontitis.7. The virulence factors (cytolethal distending toxin and capsular polysaccharide) from A.actinomycetemcomitans and a protection mechanism against infection of A.actinomycetemcomitans were clarified.8. The school dental health examination was performed in adolescent students, and the data on periodontal condition was accumulated.