Dental Caries Status and Associated Factors Among Adults in China: Findings From the FDI Oral Health Observatory

Introduction and aims To describe dental caries status and identify associated factors among Chinese adults attending dental care facilities using the FDI Oral Health Observatory data. Methods This cross-sectional study included 2233 adult patients in 31 provinces of China in 2020. Data were collected using standardized self-administered questionnaires and oral examinations conducted by trained dentists. Caries-related indicators included decayed teeth (DT), filled teeth (FT), and decayed and FT (DFT). Sociodemographic characteristics, oral hygiene behaviours, dietary habits, dental service utilization, and self-rated health were assessed. Chi-square, Mann–Whitney U , or Kruskal–Wallis tests compared group differences. Binary logistic regression identified factors associated with DFT > 0, DT > 0, and FT > 0. Given excess zeros and overdispersion in DFT counts, a zero-inflated negative binomial model was applied. Results Among 2233 participants, the prevalence of DFT > 0, DT > 0, and FT > 0 was high. Higher caries risk correlated with older age, lower education, infrequent toothbrushing, nonuse of fluoride, poorer self-rated health, and higher sugar intake. Female participants were more likely to have FT. Insured participants showed higher DFT, DT, and FT. The zero-inflated negative binomial model confirmed substantial associations between behavioural and socioeconomic factors and DFT counts. Compared with the 4th National Oral Health Survey, this population had higher caries prevalence, treatment rates, and sugar intake, despite better oral hygiene and more frequent dental visits. These differences might partly reflect the clinic-based nature of the present sample, in contrast to the population-based National Oral Health Survey. Conclusion Adults visiting dental care facilities in China had a high burden of dental caries. Despite having better oral health behaviours than the general population, their caries burden remained elevated. Greater emphasis on dietary and caries risk assessment could be needed in dental practice.