Objective  To investigate and analyze the epidemic trend of periodontal disease in Sichuan Province.   Methods  Questionnaire investigation and clinical examination were carried out in some randomly selected districts and populations. Periodontal disease-related social factors and lifestyle were analyzed. Data obtained from the returned 400 questionnaires including general condition

health behavior

oral health

oral hygiene

dental treatment

general health

gingival index (GI)

simplified oral hygiene index（SOHI），probing depth (PD)

bleeding on probing (BOP) were analyzed by multiple factor analysis and logistic regression analysis.   Results  Among the 400 patients investigated

the incidence of periodontitis was 87.8%

and the mean value of PD

clinical attachment loss (CAL)

OHSI

GI and BOP was 1.71±0.81

2.44±1.73

2.53±1.17 and 1.926±0.224 mm

respectively. Bleeding occurred at least in one site of 82.28% patients during probing. Bleeding in gum accounted for 17.67% of all detected sites. Logistic regression analysis and multiple factor analysis showed that food containing rich fibers

teeth brushing for about 3 minutes each day and regular clean of teeth could protect teeth against periodontal disease

while smoking

age

and residence place were the risk factors for periodontal disease.   Conclusion  The incidence of periodontal disease is high in Sichuan Province. The knowledge about oral health and periodontitis is very poor. Education on oral health and prevention and treatment of periodontal disease should be strengthened.