This document summarizes a case study on dental fluorosis in the Vavuniya district of Sri Lanka. Water samples were collected from 72 wells and tested for fluoride concentration. Fluoride levels above the WHO recommended level of 1.5 mg/L were found to cause dental and skeletal fluorosis. The highest number of fluorosis patients were found in the Chettikulam area, where the highest fluoride level of 1.52 mg/L was recorded. Positive correlations were observed between fluoride levels and electrical conductivity, pH, and well depth. The study identified areas with high fluoride concentrations in groundwater and high rates of dental fluorosis. More research was recommended to develop techniques for removing fluoride from drinking water in affected rural

1. DENTAL FLUOROSIS: A CASE STUDY IN VAUVNIYA
DISTRICT, DRY ZONE OF SRI LANKA
K.S.Sivanesan

2. Introduction• Fluoride
Fluoride is an essential element for both human and
animals health it, becomes toxic when ingested in
excessive doses and WHO recommended level of
Fluoride is 1.5 mg/L for human consumption.
Figure 1

3. Dental Fluorosis
Very high incidences of dental and in some cases
skeletal fluorosis mainly caused by excessive
fluoride in drinking water.
(Edmunds & Smedley, 2005; Dissanayake & Chandrajith, 2007)
Fluorine has high electro negativity and solubility, and
hence occurs as F− in natural water.
(Liu and Lipták, 2000)

4. Symptoms
• Discolored teeth.
• Yellow stained teeth
• Brown stained teeth.
• Chalky white teeth patches.
• Soft Spots (or weak teeth)
• Initially there may be a few white flecks or small
pits on the enamel of the teeth.
Figure 1:Symptoms of Dental Fluorosis from our study area

5. Drinking water
 High fluoride contents in ground water are
very big problem in the dry zone of Sri Lanka.
 Very high incidences of dental and in some
cases skeletal fluorosis mainly caused by
excessive fluoride in drinking water
(Edmunds & Smedley, 2005; Dissanayake & Chandrajith, 2007).

6. Why this Research was important?
• During the year 2013 it has been reported that
about 324 patients have taken advices from the
dental care unit of the Vavuniya general hospital
to related to dental florosis and they majority of
the patients were from the Chettikulam area 86
were identified to be affected by dental fluorosis.

7. Concentration Impact on health
0.0-0.5 Limited growth and fertility, dental caries
0.5-1.5 Promotes dental health, prevents tooth decay
1.5-4.0 Dental fluorosis (mottling of teeth)
4.0-10.0 Dental fluorosis, skeletal fluorosis (pain in back and neck bones)
>10.0 Crippling fluorosis
Table 1: Concentration of Impact on health fluoride (mg/L)

8. Method
Seventy two (72) water samples were collected
systematically from the wells of families
including both patients and non-patients at five
villages of the Vavuniya district in Northern
Province, Sri Lanka, with special focus on
fluorine contamination.
Figure 2: A sample collected well

9. A sampling campaign was
undertaken in the dry zone of Sri
Lanka in Vavuniya.
Figure 3: Study area

10. Method
 .Water samples were collected at 20 cm depth from
water table of each well using a water sampler.
Samples were drawn with a precleaned plastic
polyethylene bottle.
 Prior to sampling, all the sampling containers were
washed and rinsed thoroughly with the groundwater.
 Fluoride concentration was determined using UV
visible spectrophotometer.
 Electrical conductivity, pH were measured using
digital meter immediately after sampling.

11. • Field measurements of temperature was made
during sampling. EC was determined by using
CE470 conductive meter.
• Total 90 peoples were examined in study area for
dental fluorosis.
• Quality control was achieved by preparation and
analysis of blank samples, and by using duplicate
sub-samples and standard materials.
• The data were then analyzed statistically.

12. Result and Discussion
Sample Vilage
Water (m) pH EC (µs/cm) F (mg/L)
Thonikkal (17)
5.95 7.16 528.47 0.63
Chettikulam(18)
6.09 7.15 720.78 0.77
Kovilkulam (14)
6.01 7.17 362.43 0.69
Vairavapuliyankulam (9)
6.06 7.16 260.00 0.64
Poonthotam (14)
4.86 7.00 686.14 0.47
 The lowest and the highest average water level were
observed as 3.9 m and 7.3 m .
 Electrical conductivity range from 120µs/cm to 1952µs/cm.
 Fluoride concentrations in the study area vary from 0.14 to
1.52 mg/L respectively.
Table 2:Average result of selected places

13. Figure 4: Correlation between the EC and pH

14. Figure 5: Correlation between the Water table and Fluoride.

15. Figure 6: Corrilation between the pH and Fluoride

16. Figure 7: Fluoride depended on EC

17. Discussion
• The lowest and the highest average water level were
observed as 3.9 m and 7.3 m
• F concentration of 32 wells higher than the desirable
(0.6mg/L) level.
• Out of the 72 wells, only six wells were observed with
higher F concentration than the WHO standard
maximum (1.5mg/L) level.
• Out of the 90 people, only 23 peoples observed as dental
fluorosis patients. Highest number of fluorosis patients
observed in Chettikulam area was 18.

18. • The highest fluoride value recorded in the
Chettikulam area was 1.52 mg/L. A positive
correlation between fluoride concentration and
well depth was observed.
• Areas with high fluoride ion concentrations in
their groundwater supplies and high
percentage morbidity of dental fluorosis have
been identified.

19. Conclusion
 Consumption of ground water with the exceeded
fluoride concentration than 0.6 mg/L can be
considered as an exposure factor for dental
fluorosis in the Vavuniya district.
 Areas with high fluoride ion concentrations in
their groundwater supplies and high percentage
morbidity of dental fluorosis have been identified.

20. Recomandation
• Proper research needs to be initiated in order to
develop cheap and technologically simple
processes for small-scale removal of fluoride from
fluoride–rich groundwater or developing
alternative sources of supply in areas where there
is such a problem especially in rural areas.
Ground water and fluorosis related status studies
not enough in the studied area, should encourage
the research studies in dry zone of northern part.
.

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•

22. Aknowadge to
Vavuniya General Hospital staffs.
Figure 8:Vavuniya General Hospital

23. THE END