Abstract: Objective To understand the oral health status of middle school students in Jiangsu Province by investigating clinical periodontal indexes such as gingival bleeding and dental calculus number among middle school students, and to provide a reliable theoretical evidence for formulating oral health care for middle school students in Jiangsu Province. Methods A total of 3914 middle school students aged 12-15 years old were selected by the method of multistage, stratification, equal capacity and simple random. The gingival bleeding, dental calculus, periodontal pocket depth and the attachment loss of the 15-year-old students were examined. Then the mean was analyzed by Kruskal-Wallis H Test, and the rates were analyzed by Chi-squared Test. Results The prevalence rate of gingival bleeding among middle school students aged 12-15 in Jiangsu Province was 89.68%. There was no significant difference in gender, but the prevalence rate of gingival bleeding in rural areas was significantly lower than that in urban areas (P < 0.001). The prevalence rate of dental calculus was 84.59% and the prevalence rate of dental calculus in males was significantly higher than that in females (P < 0.05), and that in rural areas was significantly lower than that in urban areas. The prevalence rates of gingival bleeding at 12, 13, 14 and 15 years old were 89.16%, 89.05%, 89.06% and 91.46% respectively, without significant statistical difference. The prevalence rates of dental calculus were 79.75%, 83.16%, 85.48% and 90.02% respectively. There were statistical differences between 12 and 14 years old, 12 and 15 years old, 13 and 15 years old, 14 and 15 years old (P < 0.05). Conclusion The prevalence rates of gingival bleeding and calculus of middle school students aged 12-15 in Jiangsu Province is high, but the control of gingival inflammation is poor, which is significantly lower than the national average. Therefore, it is necessary for middle school students to strengthen oral health education.

Key words: periodontitis, oral epidemiology, Jiangsu Province