Objective: To understand the prevalence and influencing factors of Children s Dental Fear (CDF) among 12-15 year-old children in Shenzhen city, so as to provide a framework to alleviate CDF and promote oral health. Methods: Multi-stage stratified random sampling was used to select 5 509 children, aged 12-15 years, to participate in this study, which was carried out from October to November, 2018. The Children s Fear Survey Scheduling-Dental Subscale (CFSS-DS) and oral health examinations were conducted in Shenzhen. Results: The prevalence of dental fear in children aged 12, 13, 14, and 15 years in Shenzhen was 30.3%, 30.5%, 33.6%, and 26.9%, respectively(χ 2=11.97, P=0.01). The CFSS-DS scores were(29.86±13.23)(29.72±13.59)(31.23±14.47)(29.79±13.24), respectively(F=3.60, P=0.01). The CFSS-DS scores of male and female participants were (27.92±13.69) and (32.62±13.12)(t=-12.97, P<0.01), respectively, and the CDF prevalence rates were 23.8% and 38.8%, respectively(χ 2=159.29, P<0.01). Multivariate Logistic regression analysis showed that gender, brushing frequency, visiting experience, oral knowledge level, oral health attitude, oral health and general health status were correlated with CDF (P<0.05). Conclusion Attention should be paid to the prevalence of dental phobia among children aged 12-15 years in Shenzhen, and comprehensive intervention measures should be taken to improve children s oral health.

Objective: This epidemiology survey is intended to assess the periodontal health conditions of 12 to 15-year-old adolescents and the associated factors in Shenzhen. Methods: The study utilized a multistage stratified cluster method and recruited 5 509 middle school students aged 12 to 15. Gingival bleeding and calculus were conducted and a self-reported questionnaire was administered. Additional periodontal pocket depth and attachment loss examination were performed in the 15-year-age group. Periodontal conditions and the associated factors were analyzed by t-test, Chi-square method and Logistic regression. Results: The prevalence of gingival bleeding and calculus among adolescents was 43.95% and 44.25%, and the prevalence of periodontal pockets ≤3 mm was 0.57%. No periodontal pockets ≥6 mm or attachment loss ≥4 mm were detected. Gender, family income and frequency of teeth brushing were significantly associated with calculus detection (P＜0.05). The use of fluoride had an significant effect on gingival bleeding detection and calculus detection (χ 2=9.70，6.16，P＜0.05). Conclusion The periodontal health condition among 12-15 years old adolescents in Shenzhen is generally better than the national level. Adolescents living in high-economic districts and females had better periodontal health condition. The government can promote health education in schools and popularize the use of fluoride to improve the periodontal health condition among adolescents.