To change your life ,you need to change your priorities .Thankyou it is very to dental students .

1. A Presentation by:
Md. Kalam Safi
Roll No:15
BDS Third year
KDCH 10Th Batch
Dr. Sujita Shrestha

2. (Fluoride was established as the positive factor
according to ‘Shoe Lether Survey in 1931 US
public health “ Dr.Trendly .H .Dean”).
The fluoride is the ionic form of the element
fluorine .
Fluoride is a mineral found throughout the earth’s
crust & widely distributed in nature .
Fluoride may occurs in combined form in a wide
variety of minerals .

3. In Lithosphere:
Rock and soil
 Fluorspar: 49%
Fluorapatite : 3.4%
 Cryolite : 54%

4. Small amount: Fruits, vegetables ,cereals
Rich amount :sea foods ,Tea leaves etc.

5. Teeth and skeleton have a highest concentrations
of fluoride.
Due to affinity fluoride to calcium.
Fluoride content of teeth increases rapidly during
early mineralization periods and continues to
increase with age ,but at as lower rate.

6. Distributed fluoride in body tissue and organ :
1. Fluoride in Soft tissue: Amt.of fluoride in pulp
(100-650 ppm) .
2. Fluoride in Bone: 99% fluoride found in calcified
tissue in human body .
3. Fluoride in Saliva: Amt.of fluoride v.low(0.007-
0.005 ppm)
4. Fluoride in Enamel: Outer enamel 2200-3200 ppm

7. 5.Fluoride in Dentin: Fluoride conc. is more in dentin
than in enamel .
6.Fluoride in Cementum: Amt. of fluoride 4500 ppm.
7.Fluoride and Dental Plaque: Amt.of fluoride 15-64
ppm .

8. The benefits of fluoride in the reduction of dental
caries have been known for years,
But its exact mechanism of action is not
completely understood .
The mechanisms by which fluoride increase caries
resistance may arise from both systemic and
topical application of fluoride.

9. A number of proposed mechanisms have been
identified which are assumed to work
simultaneously and can be grouped as follows :-
Increase enamel resistance /Reduction in enamel
solubility .
Increase rate of Posteruptive Maturation .
Remineralization of Incipient lesions .
Interference with Plaque Microorganisms.
Modification in Tooth Morphology .

12. Fluoride converts hydroxyappatite in teeth into
fluoroappatite which is less soluble in acids
produced by bacteria in oral cavity .
Fluoride inhibits demineralization in several ways:
• Reduction in bacterial acid production and
acidurance .
• Equilibrium solubility of apatite is reduced .
• Reduction in dissolution rate of fluoridated apatite
crystals.

14. a. Low concentration of fluoride .
b. High concentration of fluoride .
Hydroxyapatite
Low concentration of fluoride
Fluorhydroxyapatite + F
Fig . Low concentration of fluoride .
Fluorapatite

15. Hydroxyapatite + High conc. of fluoride
CaF2 + PO4+ Hydroxyapatite
Hydroxyapatite + Fluoride
Fluoridated hydroxyapatite (FHA)
Fluorapatite
Fig : Both low and high concentration of fluoride
showing mechanism of fluorapatite .
Repeated exposure to fluoride
over long period of time .
CaF2 Ca++ and F

16. Enamel structure (carbonated
apatite more soluble in acid )
Hydroxyapatite (less soluble in
acid )
Fluorapatite (least soluble in
acid )
Fluoride uptake

17. Fig: Fluoride uptake

18. Fluoride increase the rate of mineralization of
hypomineralization area of the newly erupted
teeth and prevents caries as hypomineralized area
is more prone to dental caries .
The mineral ion and organic material are deposited
from the saliva .
Post eruptive maturation involves deposition of
minerals into hypomineralized areas ,while
remineralization involves deposition of minerals
into demineralized .

19. Fluoride enhances the remineralization process by
accelerating the growth of enamel crystal (prevent
dental caries ).

20. Plaque Bacteria
Fermentable Carbohydrate(sucrose)
White spot lesions
Remineralization
Fig :Effect of Fluoride on Demineralization and
Remineralization .
Fluoride Availability
Remineralization Demineralization

21. Fluoride enhances rate of remineralization from
calcium phosphate solutions ,where two folds
increase in remineralization of white spot is
observed.
Enamel and dentin demineralization is not a
continuous ,irreversible process.

23. Fluoride at low level is bacteriostatic and at high
level is bactericidal .
Fluoride inhibits bacterial enzymatic processes
involved in carbohydrate metabolism .
ENOLASE PHOSPHATASES CATION TRANSPORT
Fluoride
High conc. Low conc.
BacteriostaticBactericidal
FLUORIDE INHIBITS

24. If fluoride is ingested during the tooth
development ,slightly smaller teeth with shallow
fissures are formed .
Such change in morphology would tend to
decrease the caries susceptibility of teeth by
making them more self cleansing .
Fluoride Ingested
During Tooth
Development
Shallow Fissures
Decreased Diameter
Smaller Cusp Tip

25. Fig: Comparission of gross morphology of posterior tooth :
Fluoridated & Non- Fluoridated Areas.

26. Fluoride in recommended concentration is
definitely beneficial to health .
In excess amount it is harmful to the body .
Appropriate fluoride intake in different population
groups in different areas has to be ascertained on
the basis of fluoride concentration in food and
water resources taken by the local population .

27.  Soben Peter : Preventive and community
Dentistry.
Internet sources etc.