Caries Trends in Czech Preschool Children over Last 20 Years

Objectives: To evaluate trends in caries experience of 5yr olds in the Czech Republic since 1994. Methods: Data from two sources were available. (i) A series of cross-sectional national surveys of 5yr olds was conducted by the Institute of Health Information and Statistics (IHIS) and supported by the Czech Ministry of Health in years 1994, 1997, 2000, 2003 and 2006 (n=3383, 3578, 3186, 3337 and 3561, respectively). Dental data were collected from all general dental practitioners in the country and comprised of all 5-year old patients examined in a dental office within one calendar month (each subject was included only once). (ii) Institute of Dental Research (IDR) conducted its own, smaller, IDR surveys in years 1998, 2001, 2005 and 2010 (n=435, 297, 285 and 583, respectively). Calibrated examiners assessed geographically stratified sample using D3 caries diagnostic threshold. For each survey, the following parameters were calculated: mean dmft; mean dt, % of caries-free subjects. For the assessment of the trends, regression modelling was used separately for each series of surveys. Results: Over the respective periods, in both IHIS and IDR surveys: a significant trend of declining mean dmft and mean dt and increasing trend of percentage of caries-free was observed (p<0.05). Dmft reduced from 3.53 to 2.69 (IHIS) and 3.68 to 2.98 (IDR), respectively, while % of caries-free children increased from 23.9 to 42.2% (IHIS) and from 26.7 to 44.9% (IDR), respectively. Conclusions: A positive trend of caries experience over a period 1994-2010 was observed both for national monitoring and smaller epidemiological studies that differed in data collection methodology (patients x general subjects, non-calibrated x calibrated examiners). Consistency observed in trends of individual parameters enhances the validity of the results of both set of studies. Acknowledgements: Grant Agency of the Ministry of Health (CZ), Grant No. NS10599-3/2009.