Prevalence and Associated Factors of Dental Calculus Among Miao and Buyi Ethnic Adults in Huishui County, Guizhou Province, China: A Cross-Sectional Study

Background To investigate the prevalence and key risk factors of dental calculus among adults in Huishui County, Guizhou Province, China. Materials and methods A total of 4,216 adults were selected via multi-stage stratified random sampling. All participants completed questionnaires and received oral examinations. Univariate analysis and multivariate logistic regression were used to identify risk factors. Results The overall prevalence of dental calculus was 71%. Multivariate analysis identified significant risk factors, including Han ethnicity, age 60–80, farming occupation, low education and income, infrequent or short-duration brushing, heavy and long-term smoking, daily alcohol use, short sleep, high physical activity, low screen time, and spicy or sweet dietary preferences. Notably, local dietary habits involving Zanthoxylum consumption showed a protective effect. Conclusions Dental calculus is highly prevalent in this population and strongly associated with behavioral and socioeconomic factors. Oral health interventions should consider ethnic dietary practices and lifestyle characteristics for effective prevention.