Caries prevalence and its relation to water fluoride levels among schoolchildren in Central Province of Saudi Arabia

Objective: To determine dental caries prevalence and severity among primary and intermediate schoolchildren in Riyadh and Qaseem Regions, and to determine any correlation between dental caries and fluoride levels in drinking water. Design: Cross-sectional. Methods: 1,104 children; 431 (67-year-old) primary schoolchildren (249 in Riyadh and 182 in Qaseem) and 673 (12-13-year-old) intermediate schoolchildren (392 in Riyadh and 281 in Qaseem) were examined for dental caries utilising the WHO criteria for diagnosis of dental caries. Results: In primary schoolchildren the prevalence of caries was 91.2% both in Riyadh and Qaseem. The mean dmft scores were similar in Riyadh (6.53, SD 4.30) and Qaseem (6.35, SD 3.83). Among the intermediate schoolchildren the prevalence of dental caries was slightly higher in Riyadh (92.3%) than Qaseem (87.9%). The mean DMFT score was higher in Riyadh (5.06, SD 3.65) as compared with Qaseem (4.53, SD 3.57) with marginal statistical significance (p = 0.057). Among the primary schoolchildren there was statistically significant (p < 0.05) difference in mean dmft scores at various fluoride levels with lowest dmft scores at the optimum water fluoride level (0.61-0.80ppm) and highest at two extremes i.e. 0.0 to 0.3ppm and > 2.5ppm, while in intermediate schoolchildren no significant difference in overall mean DMFT scores of children at various water fluoride levels could be found. Conclusion: The caries experience among the primary and intermediate schoolchildren in Riyadh and Qaseem was very high, and that there was no linear correlation between water fluoride level and caries experience in these children.