DENTAL FLUOROSIS: A CASE STUDY IN VAUVNIYADISTRICT, DRY ZONE OF SRI LANKA

K.S.Sivanesan

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

Dental FluorosisVery 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)

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

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).

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.

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)

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

A sampling campaign was undertaken in the dry zone of Sri Lanka in Vavuniya.

Figure 3: Study area

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.

• 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.

Result and DiscussionSample Vilage Water (m) pH EC (µs/cm) F (mg/L)

Thonikkal (17) 5.95 7.16 528.47 0.63Chettikulam(18) 6.09 7.15 720.78 0.77Kovilkulam (14) 6.01 7.17 362.43 0.69Vairavapuliyankulam (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

Figure 4: Correlation between the EC and pH

Figure 5: Correlation between the Water table and Fluoride.

Figure 6: Corrilation between the pH and Fluoride

Figure 7: Fluoride depended on EC

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.

• 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.

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.

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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Aknowadge to

Vavuniya General Hospital staffs.

Figure 8:Vavuniya General Hospital

THE END