3 prevention of dental caries ii Lama K El Banna

1. Prevention
Of
Dental Caries
II
Dr. Ahmed Al Shawi

2. Topical
protection of
teeth:

3.  This includes all measures applied to increase the
resistance of the intact outer tooth surface.
 Among these measures are operative dentistry,
prophylactic odontotomy, prophylactic fissure filling,
topical chemotherapy, fissure sealants, preventive resin
restoration and atraumatic dentistry (ART) are the most
essential.

4. 1- Fissure
sealants:

5. 1- Fissure sealants:
 Fissure sealants are materials used to (correct) seal
deep pits and fissures and change them into non-
retentive surfaces. There is considerable evidence
that a significant caries reduction observed when
fissure sealants are correctly applied to deep pits
and fissures of newly erupted teeth.

6. Types of sealant materials:
 Nowadays several materials are commercially
available. These are either chemically cure or light
cure (using visible light). These are:
1. BIS- GMA resin (filled or unfilled).
2. Glass ionomer cement.
3. Compo mer.

7. Application of pit and fissure sealants:
 It should be noted that newly erupted posterior teeth with
deep pits and fissures are the suitable teeth for application.

8. Steps of application are:
1. Remove any debris using pumice slurry on small brush or
prophylactic rubber cup.
2. Wash the tooth with air water spray.
3. Isolate the tooth with cotton rolls and use saliva ejector.
4. Dry the tooth with compressed air.
5. Etch the occlusal tooth surface with enamel etching solution
or gel (37% ortho-phosphoric acid) for one minute.
6. Wash thoroughly with air water spray.

9. Steps of application are:
7. Dry with compressed air until chalky white enamel
surface appears.
8. Apply the fissure sealant with little brush.
9. Polymerize light cure sealant for 20 seconds keeping the tip
of the light gun as close to the surface as possible.
10. Check the height (high spots) of the polymerized material
and correct with fine stone when possible.
11. Check the success of sealant application at 6 monthly
period .

12. 2- Fluoride Varnish:
 It is a sticky yellowish protective coating in a resin base that
is painted over the teeth surface in an attempt to prevent
dental caries or to allow remineralization of initially
demineralized enamel surfaces.
 Studies showed about 18-70% reduction of smooth surface
caries.

13. Advantages:
1. Easy application.
2. Patient's acceptance.
3. Higher fluoride than gels and foam.
4. Negligible amount of ingested fluoride.

14.  It has the ability to adhere to enamel for long periods and
thus release fluoride slowly to the teeth.
 The commercially available varnishes contain either 5%
Sodium fluoride or 1 % Fluorosilane.
 It is applied by brush and allowed to harden for 5-6 minutes.
The application should be repeated at 3-6 months interval.

15. 3- Preventive resin restoration:
 This procedure was born of fissure sealant.
 The technique is based upon restoring minimal carious lesion
usually in young permanent molars with minimum removal of
tooth structures, while concomitantly preventing caries from
attacking other pits and fissures on the same surface without
mechanically removal of these areas.

16. Technique:
 A small round bur may be used for access and removal any
carious tissue.
 The tooth is then etched as for sealant application, and a pit
and fissure sealant is applied.
 A composite of thin consistency may be used.

17. 4- Atraumatic restorative treatment (ART):
 The two main principle of ART are:
1. Removing carious tooth tissue using hand
instruments only.
2. Restoring the cavity with adhesive filling
material currently as glass ionomer.

18. Carious cavities suitable for ART should be:
A. Involving the dentin with no pulpal involvement.
B. Accessible to hand instruments.

19. The advantages of ART include:
1. Use of easily available and inexpensive procedure to
conserve sound tooth surfaces.
2. Permit oral health care workers to reach people who
otherwise never would have received any oral care; such
as handicapped, villages in rural and suburban areas,
homebound, institutionalized people and economically less
developed countries.

20. Laser Light in
preventive
dentistry:

21. Laser Light in preventive dentistry:
 Recently, laser has been introduced for use in dentistry
.Different approaches has been thought to be promising in
caries prevention for:
1. Increasing the resistance of dental tissues to caries by
reducing the rate of demineralization.
2. Sealing pits and fissures and homogenizes the enamel
surface by melting structural elements.

22. Laser Light in preventive dentistry:
3. Laser application encourages fluoride uptake by dental
tissues.
4. Laser application to carious lesions vaporizes enamel caries
and adjacent sound enamel fuses and eliminates small
defects.
5. Application of laser prior to application of fissure sealants
improves its retention.

23. The only topical method with
real effect in caries control is the
topical application of fluoride in
one way or the other.

24. Prevention of
Dental Caries
with Fluoride:

25. What is fluoride?
 It is one of the halogens.
 It is the most active element of this group. It is not present in
the free form.
 Fluoride is the combined form of the free element. It is
difficult to obtain a sample of calcium compound from a
natural source in a completely fluoride free condition.
 It is present in soil, seawater, rainwater, seafood, etc.
 Fluoride is the only proved diet substance to be of
anticariogenic benefit for humans.

26. Fluoride can be used to control dental caries either by:
1. Systemic route, i.e. by ingesting fluoride.
2. Topical application.

27. Mode of Action of Fluoride:
 The role played by fluoride in the control of dental
canes is mainly as
follows:

28. 1. Ionic exchange of fluoride with the hydroxyl group of
calcium hydroxyapetite in the surface layers of enamel
changing it into fluoroapetite, which is less soluble in acids.
2. Enzymatic inhibition interfering with the breakdown of
glucose to lactic and pyruvic acid. Both phosphatase and
anulase enzymes are inhibited by fluoride.
3. Bacterial inhibition, fluoride has a direct inhibitory effect
on the bacteria of the dental plaque.
4. Fluoride has the ability to precipitate minerals from saturated
solutions.
As saliva is saturated by minerals, fluoride favors the
precipitation of the __ calcium phosphate on the surface of
enamel, so it aids in remineralization of partially
demineralized enamel in early caries.

29. 5. Fluoride lowers free surface energy. This will decrease the
plaque accumulation on the treated enamel surface.
6. Action on tooth size and morphology: In communities with
fluoridated water supply, there is a trend towards shallower
fissures and lower cusp height and smaller tooth size. This
will decrease caries susceptibility

30. Sources of Fluoride:
 Humans obtained fluoride three sources: water, foods and air.
Two of them, water and food, may contribute significant
amounts to the daily intake.
 Water from deep wells and artesian wells usually provide high
natural fluoride concentration.
 Most vegetables, fruits and dairy products contain low amount
of fluoride.
 Meat also contain little fluoride but seafoods (fish sp. salmon
and sardines, shrimp, crab, etc) may contain 2.5 ppm.
 Most beverages contain amounts of fluoride especially tea.

31.  Fruit juices and soft drinks are generally low in fluoride, but
the fluoride content of the water used in the preparation of
such beverages or in the cooking of food will be reflected in
the fluoride concentration of the final product.
 The total amount of fluoride consumed daily will depend
upon both the concentration of the fluoride in the water and
food as well as the amount consumed.
 The recommended optimal fluoride doses for community
water supplies vary with the annual mean of the maximum
daily temperature (0.7 to 1.2 ppm).
 The average diet provides 0.2-0.3 mg of fluoride daily.

32. Fluoride Content of Enamel:
 Tooth enamel is composed mainly of hydroxyapatite and a little
proportion of calcium carbonate Traces from other elements
present either incorporated in the structure of the crystals or
concentrated on the enamel surface.
 It was noticed that there is an inverse relationship between
fluoride and carbonate concentrations in enamel.
 Fluoride is concentrated at the surface and decreases towards the
amelodentinal junction.
 Its concentration in surface enamel reaches 2000-3000 ppm in
water-fluoridated areas.

33. Uptake of Fluoride by the Teeth:
 Fluoride is incorporated in enamel and dentine in two stages:
 Before eruption:
 During Calcification, traces of fluoride incorporated into the
crystalline structure of appetite lattice. Further amounts of fluoride
are taken up by the external enamel surface from the surrounding
tissue fluids before eruption.
 After eruption:
 Enamel surface continues to pick up fluoride derived from diet,
water and saliva. The post-eruptive acquisition of fluoride continues
throughout life and is directly proportional to the concentration in
food and water ingested.

34. Toxicity of Fluoride:
 High doses of fluoride are toxic and may be lethal
Fortunately, this is rare and only few accidental cases are
reported.
 The severity depends upon the amount ingested and the
duration of intake.
 Chronic fluorosis results in skeletal or dental changes.
 Mottled enamel may result with various degrees of severity
when water fluoride concentration is (6-8 ppm).
 Later in life, the ingestion of high levels of fluoride may result
in bony deformities joint fixation and calcification of the
ligaments.

35. Methods of Providing Fluoride:
 This can be achieved either by ingesting calculated amount
of fluoride to be incorporated in the developing teeth, or
topically applying fluoride preparations on exposed tooth
surfaces to increase their resistance to cariogenic processes.

36. A. Systemic
Fluoride:

37. 1. Water fluoridation:
 There is an inverse relationship between the fluoride level in
drinking water supplies and the incidence of dental caries.
There is also a direct relationship between fluoride level and
the number of caries free individuals in the community. This
beneficial effect continues associated with increased fluoride
levels of about 1-1.5 ppm. It should be noticed that there is
also a direct relationship between fluoride level and the
incidence of mottled enamel. A fluoride concentration of 1
ppm was found to be optimum regards effective anticaries
effect and lower mottled enamel. In areas of communal water
supply with less than 1 ppm fluoride, the concentration of
fluoride is adjusted to reach this level. Later Fluoridation is the
most economical way for combating dental caries at the
community level.

38.  It is recommended that optimal dose of fluoride ingested
daily in children from 0.5 -1.0 mg fluoride (WHO) .
 So this 1 ppm fluoride concentration is suitable for countries
with cold weather whereas in countries with hot weather the
concentration of fluoride in public water supplies should be
lower and this depends on the daily water consumption
which is usually double or triple them that of cold weather .

39. 2. Fluoridation of school water
supply:
 Where fluoridation of communal water supply is not possible
fluoridation of school water supply can be approached.
School children are exposed to the benefit of fluoridation
only during school days and hours.
 In this case higher fluoride concentration up to 5 ppm have
been tested and proved effective in caries control.
 The decrease in DMFS is about 40% with no evidence of
dental fluorosis.

40. 3. Fluoride supplements:
 When fluoridation of water supply is not feasible or possible,
fluoride supplements can be resorted to. This can be in the form of
fluoride tablets, drops or syrups. Studies have shown considerable
reduction in dental caries in deciduous and permanent dentition
when consumption of fluoride has been started early enough. The
usual dose is 0.5 mg F/day for children up to 3 years of age and 1.0
mg F/day for children over 3 years of age. The fluoride tablets
usually contain 1.0 mg F, to be crushed in water or fruit juices.
Fluoride administration should continue until the age of complete
crown formation of the second permanent molar, i.e. about the age
of 10 years. Fluoride preparations should be kept out of reach of
children to avoid over dosage. Fluoride tablets disguised as sweets
are not advised.

41. 4. Fluoride incorporation in various foods:
 To make fluoride administration, a personal choice,
incorporation of fluoride in certain foods of common use such
as salt, milk, bread, rice, etc, the fluoride enriched foods are
usually available on request.
 It is difficult to adjust fluoride concentration to satisfy the
individual personal intake as the consumption of these foods
may vary significantly from one person to another. A careful
regulation of the prescribed daily dose and a constant
cooperation by the parents is required.

42. Topically applied fluorides:
 The topical application of fluoride can be carried
out either by the patient himself or by members of
the dental profession.

43. 1. Self
administered
fluoride
applications:

44. 1. Fluoride tooth pastes (dentifrices): (Discussed before).
2. Brushing or rinsing with fluoride solution:
 Studies have shown that regular rinsing or brushing (every
week or fortnight) with 0.2% sodium fluoride will reduce
dental caries incidence. The principle to be noted is the
frequent rinsing with very dilute fluoride solution. This is to
be done after the routine tooth brushing to obtain clean tooth
surface and direct access to the enamel surface.
 Highly diluted solution (0.02%) can be used daily for patients
showing high caries susceptibility. Studies on supervised
month rinsig can be carried out in schools and evidence of
substantial success has been obtained.

45. 3. Fluoride gel:
 This is usually commercially available product
containing 1.23% fluoride. It is widely used. The
gel has added flavours.
 It has to be loaded in a special applicator to hold
the gel in place for about 4 minutes. With some
applicators, the whole mouth can be treated at
once.

46. 4. Fluoride dental floss:
 Dental floss (unwaxed) impregnated with fluoride
is a valuable topical fluoride vehicle. Flossing will
result in a significant uptake of fluoride and a
reduction in the colonies of microorganisms on the
proximal tooth surfaces.

47. 2.Professionally
applied fluoride:

48. 1. Sodium fluoride:
 The recommended procedure of 4 applications of a 2% sodium
fluoride solution, one week interval, between every
application result in an 40% reduction in dental caries
incidence.
 These 4 applications are considered a single application and
have to be applied every year.

49. 2. Stannous fluoride:
 Single annual application of 8% stannous fluoride gives about
65% reduction in caries incidence.
 Stannous fluoride solution is unstable. It has a short shelf life,
so it has to be prepared freshly for each application by
dissolving 0.8 gm. ¬Of stannous fluoride in 10 ml distilled
water.
 The solution has a disagreeable astringent taste, and it
discolors decalcified enamel.

50. 3. Acidulated phosphate fluoride:
 Combination of sodium fluoride with phosphoric acid;
1.23% sodium fluoride in 0.1 M orthophosphoric acid
produces an acidulated phosphate fluoride mixture which
when applied topically to the teeth of children on an
annual basis has decreased caries from 50-70%.
This agent is stable, so it does not have to be prepared
freshly for every treatment as in cases of stannous
fluoride; also, not discolor decalcified enamel.

51. Procedure for
applying
fluorides
topically

52. a) Stannous fluoride:
1. A thorough prophylaxis should be performed; each available
tooth surface should be cleaned and polished with pumice
and rubber cup. It is preferable to add one drop of 8%
stannous fluoride solution to the polishing paste.
2. The upper and lower teeth on one side are isolated at a time,
this is achieved with a long cotton roll in the upper and lower
buccal sulci and a short roll in the lingual area. A saliva
ejector helps to keep the area dry. The teeth are then air-
dried.
3. An 8% stannous fluoride solution is freshly prepared and
applied to all surfaces of the dried teeth with a cotton
applicator. The teeth are kept moist with the solution for 4
mm. by applying it every 15 to 30 sec .

53. b) Acidulated phosphate fluoride:
 The same technique as for stannous fluoride.

54. c) Sodium fluoride:
1. A thorough prophylaxis is performed.
2. Teeth on one side are isolated as mentioned before.
3. Teeth are then dried and the 2% sodium fluoride solution applied
to each tooth surface including the interproximal surfaces with a
cotton applicator. The solution is allowed to dry on the teeth for 3
to 5 mm.
4. On 3 subsequent visits, usually one week apart, the same
procedure is repeated with the exception that prophylaxis is
omitted and these 4 times are considered one application. The
teeth have to be treated every year.

55.  Sodium fluoride has a good shelf life; the solution can be
kept for a long period of time without deterioration. For
those children to whom it is difficult to apply fluorides every
year; it is customary to treat the teeth with topical fluorides
at 3,7,10 and 13 years of age. This is to insure that all the
primary teeth and most of the permanent ones receive the
beneficial effect of fluorides just after their eruption.

56. d) Prophylactic Paste:
 The routine use of prophylactic pastes containing fluoride in
the dental office is expected to increase the fluoride content of
surface enamel and consequently, its resistance to add attack.
 This will be advantageous when carried out every six months
as part of the regular dental examination.
 The most recently available are stannous fluoride - zirconium
silicate paste and an acidulated phosphate fluoride - silicone
dioxide paste.