Dental fluorosis & urinary F concentrations of Lao children

Methods: Two provinces were selected, Vientiane and Pakse, one hundred 3-9 year olds were participated. To examine the dental fluorosis status, Thylstrup Fejerskov index was used. Examination was done by one dentist and final decision was made with collaboration of other 2 dentists (P&M).

To analyse the urinary F concentration, the second urine sample was collected from each child. The total volume of urine was recorded. Fluoride content of a urine sample & drinking water was determined using ion-selective electrode after addition of TISAB II by a direct method.

results: In Vientiane, among 50 investigated children only two 6-9 year olds showed TF score 1, in Pakse 12 among 50 showed fluorosis(TF score 1 = 8, TF score 2 = 3, TF score 4 = 1). The mean F concentration in drinking water were 0.05 ~ 0.1 ppm of the Vientiane, 0.1ppm of Pakse(river), 0.3 ~ 0.4 ppm of Pakse(well).

In Vientiane, the mean concentration of urinary F in 3-5 year olds was 0.003± 0.002ìg/g/hr, and in the 6-9 year olds was 0.006 ± 0.004ìg/g/hr.

In Pakse, the mean concentration of urinary F in 3-5 year olds was 0.005± 0.004ìg/g/hr, and in the 6-9 year olds was 0.010 ± 0.005ìg/g/hr.

Conclusions: The concentration in the drinking water in Lao is somewhat low, and the urinary concentration in children was low. We could consider the development of a dental caries preventive program with fluoride in this area.