Material and Methods: This survey was conducted in one urban and one rural district of the Shenzhen. Sampling frame was schools with an enrolment of over 1000 children. Through simple random sampling, 11 schools were selected and all 12-year-old children were invited to attend a free clinical examination in the school by a trained examiner using a disposable mouth-mirror attached to an intraoral LED light. The tooth and periodontal health status was recorded by using the indices and diagnostic criteria recommended by the World Health Organization. A questionnaire on the child's demographic background and oral health related behaviours was completed by the parents.
Results: In early 2008, a total of 752 children (52% boys) were surveyed. Response rate was around 80%. Around half (46%) of them brush their teeth only once daily or less often. Most of the children (86%) used fluoridated toothpaste. Less than 20% had a habit of frequent intake of sweet snacks and candies. Over one-third (36%) of the children had never visited a dentist while only 9% had visited a dentist within 12 months. None of the children had healthy gums (CPI score 0) while 66% of them had calculus (CPI score 2). Prevalence of dental caries experience permanent teeth was 30%. The mean DMFT score was 0.6 (DT=0.5, MT<0.1, FT=0.1). Girls had a higher mean DMFT score (0.7 vs. 0.5, p=0.008), and so were the children who lived in rural area compared to those who lived in urban area (0.7 vs. 0.4, p<0.001).
Conclusion: Prevalence of dental caries among the 12-year-old children in Shenzhen was not high but their periodontal condition was unsatisfactory. Their utilization of dental service was low.