Research of Public Health ot Prevent Periodontal Disease

老年人的比例在不断增加，牙周病在老年人中也越来越普遍。为了延长牙齿的寿命，需要良好的牙周病预防方法。本课题的研究对象如下：1.牙周病患病率调查; 2.对11，385颗离体牙的调查结果表明，龋病和牙周病是导致老年人患龋的主要原因，分别占56%和38%。在46-55岁之间，超过50%的牙齿因牙周病而被拔除。男性因牙周病拔牙率高于女性。采用CPITN软件分析牙周病患病率。在2，228名大学新生中，98%患有牙周病。在对957名居民的调查中，牙周病的患病率为99.6%，其中18%为重度牙周炎。重度牙周炎随年龄增长而增加。男性重度牙周炎患病率高于女性，刷牙是治疗和预防牙周病的有效措施。为评价公共场所刷牙指导的效果，对40名参与者进行了研究。对自来水厂330名男工进行了口腔检查后，用一次性牙刷进行剔牙法的指导。一年半后对教学效果进行评价。所有的临床症状在3分钟的指导下都得到了显著的改善（X^2检验）。总之，牙周病几乎在所有成年人中传播，并且随着年龄的增长而恶化。本研究结果提示，应指导成年人正确刷牙，以预防牙周病的发生。

Rate of the old-aged persons are increasing, and periodontal disease is vovering over old ages. To get long life span of our teeth, good preventive methods for periodontal disease are needed. The objects of this project were as follows : 1. survey of prevalence of periodontal disease, 2. evaluation of preventive method of the disease in the public.By the study about 11,385 of extracted teeth, the main reasons were dental caries ( 56% ) and periodontal disease ( 38% ). More than 50% of teeth were extracted by periodontal disease in 46-55 years. Rate of extracted teeth by periodontal disease was higher in male than in female. The prevalence of periodontal disease were analyzed using CPITN. 98% of freshmen of the University out of 2,228 were with periodontal disease. In the study of 957 inhabitants, prevalence of periodontal disease was 99.6% and 18% of them were with severe periodontitis. The severe periodontitis was increasing with age. Comparing with the female, the male showed high prevalence of severe periodontitisl.Tooth brushing is a useful measure to cure and prevent periodontal disease. To evaluate the effect of tooth brushing instruction in public, 40 participants were studies. Periodontal health improved after 2 weeks of tooth brushing instruction, and that good condition was kept during one year.Also 330 male workers at the Waterworks Bureau were instructed in the tooth brushing method, Tooth Pick Method using one-raw brush following oral examination. The effect of the instruction was evaluated after one and half years. All clinical signs were significantly improved ( X^2-test ) by the instruction of 3 minutes.In conclusions, periodontal disease is spread almost all adults, and becomes worse with age. These results of this study suggest that an appropriate tooth brushing should be instructed to adults to prevent periodontal disease in the public health.