Water fluoridation in Ho Chi Minh city, Vietnam in January 1990 was 0.7±0.1 ppm but adjusted to 0.5±0.1 ppm in June, 2000. Objectives: To compare the effect of the change in fluoride concentrations on dental caries prevalence in 3 year-old children in fluoridated and non-fluoridated area. Methods: It was a cross-sectional study using multi-stage random stratified samples of children born in 1990 and 2001. 590 3-year-old children (420 in the fluoridated area and 170 in a non-fluoridated area) were examined in September 1993 while 604 (328 in the fluoridated area and 276 in a non-fluoridated area) were examined in March 2004. Prevalence of caries, dmft index and SiC Index (Significant Caries Index) were scored by calibrated examiners following WHO criteria. Chi-square test was used to compare caries prevalence and t-test for dmft and SiC between the two examinations. Results:
|
|
Fluoridated area |
p value |
Non-fluoridated area |
p value |
||
|
1993 |
2004 |
1993 |
2004 |
|||
|
Caries prevalence |
46.0% |
38.4% |
>0.05 |
67.6% |
62.0% |
>0.05 |
|
dmft (±SE) |
1.99±0.15 |
1.60±0.15 |
>0.05 |
3.36±0.29 |
3.41±0.25 |
>0.05 |
|
SiC (±SE) |
5.40±0.24 |
4.62±0.28 |
>0.05 |
7.63±0.42 |
8.16±0.39 |
>0.05 |