The document discusses fluoride in preventive dentistry. It provides information on the following:
- Fluoride content in the environment including soil, water, and atmosphere.
- Types of systemic and topical fluoride therapies including water fluoridation, supplements, and professionally-applied varnishes, gels, and foams.
- Details on commonly used topical fluoride agents like sodium fluoride, stannous fluoride, acidulated phosphate fluoride, and fluoride varnishes.
2. Fluorine is an element of the halogen
family, including chlorine, bromine and
iodine. Due to its reactivity, fluorine
exists almost as a fluoride. Fluoride (F)
constitutes about 0.032% of the earth’s.
Fluoride content is commonly expressed
in parts per million (ppm) which is
equivalent to 1 mg fluoride per kilogram
or liter of water.
Thus, 1 ppm fluoride equal to 1 mg
fluoride per liter of water.
What is Fluoride
3. In soil: Fluoride concentration of soil increases with
depth. In high mountain areas the fluoride content of the
soil is usually higher. In rock and soil, fluoride may occur
in a wide variety of minerals, including fluorspar contains
calcium fluoride, cryolite contains aluminum fluoride.
In waters: water with high fluoride content are usually
found at the foot of high mountains. All water contains
fluorides in varying concentrations. As many of the
minerals in the soil are soluble in water, fluoride is found
in varying concentrations in the groundwater, Sea water
contains significant quantities of fluoride at levels 0.8-1.4
mg/lt. In water from lakes, rivers, and artesian wells the
fluoride content is usually below 0.5 mg/L
Fluoride in Environment:
4. In atmosphere: fluoride originating from dust of fluoride-
containing soils from gaseous industrial waste, the
burning of coal fires in populated areas and from gases
emitted in areas of volcanic activity in nature. The
principal source of pollution are industries and mining of
phosphate and fluorspar, where fluoride rich dust travel
long distances by wind and enter food chain by depositing
on plants. Pesticides containing fluoride can have a
similar effect.
Fluoride in Environment:
6. Fluoride therapy
In general there are two type of fluoride therapy:
A. Systemic fluoridation
1. Water fluoridation
• Natural water fluoridation
• Artificial water fluoridation
i. Communal (to all community)
ii. Home water fluoridation.
iii. School water fluoridation.
2. Fluoride supplements (tablets and drops).
3. Fluoride salt
4. Fluoride milk
B. topical fluoride
1. Self-applied
i. fluoride gel
ii. Dentifrices
iii mouth rinses
2. Professionally applied:
i. Varnishes
ii. gel (APF, NaF) iii solution
7. TYPES OF SYSTEMIC FLUORIDES
Artificial water fluoridation:
Water fluoridation is defined as “controlled adjustment of the concentration of fluoride in a communal
water supply so as to achieve maximum caries reduction and clinically insignificant level of fluorosis.
The water fluoridation is one of the most common delivery methods of fluoride.
• It presents a lower cost and long range.
• However for water fluoridation to be effective it has to be a continuous process and the concentration of
fluoride has to be well controlled.
---The optimal level of fluoride in water for protection against dental caries is approximately 1 part per
million. (ppm)
--- based on many studies reduction in prevalence of dental caries in primary teeth ranged from 40%to
50%and in permanent teeth was 50% to 60%.
8. • Pre requirements of water fluoridation
1. Presence of caries in the community/public
2. Level of fluoride concentrations in their drinking water. 3. Centralized water supply to
the community
4. Community acceptance/approval.
5. Installation and maintenance cost.
School water fluoridation:
The most important points that the optimal level of fluoride = 4.5 times that a community
because:
1. Children spent only part of their time in school.
2. There are holidays and weekends and these are going to discontinuation in the uptake of
fluoride
3. They are enter the school at 6- year of age, thus the incisors are no longer at risk of dental
fluorosis.
Home Water Fluoridation:
• This type of fluoridation can be seen in the internal school and handicapped institution. It is
similar in concentration of fluoride to the communal water fluoridation
9. Fluoride supplement
• Fluoride supplements are available in different forms such as fluoride tablets, drops, lozenges.
• Fluoride tablets, drops and lozenges are not available over the counter but prescribed by the
dentist or pediatricians to individual patients or as a part of school or home based preventive
dentistry program
• Most commonly used compound is sodium fluoride
• Supplements contain measured amount of fluorides, 0.25 mg , 0.5 mg, 1.0 mg.
• They should be taken on daily basis according to the prescribed dosage schedule.
• The council of DENTAL THERAPRUTICS OF AMERICAN DENTAL ASSOCIATION
recommends the dosage schedule for dietary fluoride supplements as shown in the table
• Correct dosage is based on the concentration of fluoride in drinking water, age and weight of
the child and other available fluoride.
• Not more than 1 milligram of fluoride should be ingested each day from all available systemic
sources
Age Dose
Birth-2year 0.25 mg
2-4 years 0.5 mg
4-13 years 1 mg
10. Types of Topical Fluoride
This term refers to the use of systems containing relatively large concentration of fluoride applied locally or
topically to erupted tooth surface in order to prevent or arrest dental caries.
Topical fluoride can be used at home or applied by professional in the clinics.
Advantages:
1. Does not cause fluorosis.
2. Cario-statistic for people of all ages
3. Available only to people who desire it.
4. Easy to use.
Disadvantages:
1. Person must be remember to be used.
2. Per-capita cost is high compared to water fluoridation.
3. More concentrated professional use products can cause short-term side effects
like nausea immediately after use.
The efficacy of topical fluoride depends on:
a. The concentration of fluoride used.
b. The frequency with which it is applied and the duration of application.
c. The specific fluoride compound used.
11. Topical fluoride therapy involves:
• 1. Self-applied fluoride:
A relatively low concentration of fluoride applied by individuals themselves. The concentration of fluoride is
about (1000 ppm).
This system includes:
• a. Dentifrices
• b. Mouth rinses
• c. Fluoridated gel.
Agents can be used once or twice a day, and a combination of two types can be applied.
• 2. Professionally applied fluoride
Is a periodic application of a high concentration of fluoride to the erupted teeth by dentists or dental
hygienist every 3, 6, or 12 months.
A. Aqueous solutions
Sodium fluoride-2%
Stannous fluoride-8%
B. Fluoride Gels
Acidulated phosphate fluoride-1.23%
C. Fluoridevarnishes.
1. Duraphat
2. Fluor protector
D. Fluoride prophylactic paste.
E. Restorative materials containing devices (slow release).
12. Self-applied fluorides
Self-application of fluoride is usually carried out with groups of persons, usually children at one time, under
only general supervision, in contrast to professionally applied fluoride treatments which are expensive
because they depend upon one professionally trained person treating one person at a time, with expensive
equipment or supplies.
Requisites for self-applied fluoride agents:
• Should be completely safe.
• Should be effective for preventing caries.
• Method should be suitable for use by large groups and at a reasonably low cost.
• Should be acceptable to participants.
• Should be easy to use to ensure compliance.
• Should require few professional personnel.
• Should be able to be supervised by non-dental personnel after short periods of inservice training.
Fluoride dentifrices
Toothpaste is probably the most readily available form of fluoride, and tooth brushing is a convenient and
accepted habit in most cultures. In fact, a global survey revealed that experts addressed fluoride toothpaste
as the main reason for the dramatic decline in caries during the last decades of the 20th century.
Most toothpaste nowadays contain sodium fluoride or sodium monofluorophosphate or combination of
both as active ingredient, usually in concentration of 1000-1500 mg F/g.
13. Self-applied fluorides
Fluoride mouth rinses
Frequent use of low concentration of fluoride is more cariostatic than less frequent use of higher
concentration of fluoride for topical application.
Over the past few decades fluoride mouth rinsing has become one of the most widely used caries-
preventive public health measure.
For reasons of lowest expense, convenience in handling as well as avoidance of unpleasant taste, NaF
became the most widely used of these tested products in public health programs.
Mouth rinse products contain fluoride ion at a concentration of 200- 900 mg/L for daily and weekly use
respectively.
Fluoride Gels for Home Use
During the past 15 years, a number of fluoride gels have become available as additional measures that may
be used to help achieve caries control.
These procedures contain:
1- 0.4% stannous fluoride (1,000 ppm fluoride).
2- 1.0% sodium fluoride (5,000 ppm).
and are formulated in a non-aqueous gel base that does not contain an abrasive system.
14. Professionally applied fluoride
• Medicaments typically dispensed by dental professional in the dental office to prevent or arrest dental caries.
• Topical fluoride application are indicated for patent with active smooth surface caries and those patients in
high caries risk groups. This includes special patient groups, such as those undergoing orthodontic treatment
and in high risk groups.
Indications for use of professionally applied topical fluorides:
1. Patients who are at high risk for caries on smooth tooth surface.
2. Patients who are at high risk for caries on root surface.
3. To reduce tooth sensitivity.
4. Active decay
5. Special patient groups
6. Additional protection if necessary for children in areas without fluoridated drinking water.
15. Method of application
• Techniques followed for application of fluoride in the dental office are:
- Paint on technique, by which fluoride material applied to teeth by cotton applicator or brush.
- Tray technique: a small amount of fluoride is added to a tray then inserted in the patient mouth
Trays come in different shapes and types as foam lined or paper, custom vinyl etc.
For both techniques:
1. Teeth are cleaned first (scaling and polishing) to remove dental plaque, calculus, stain and debris. These
may interfere with the uptake of fluoride ions and reduce its effectiveness.
2. Teeth are isolated using cotton roll and saliva ejector. The head of the patient tilted forward to avoid
accidental swallowing of the materials.
3. The fluoridated agents applied following dryness of teeth for 1- 4 minutes. The amount of agent used
must not exceed 4 ml in both trays to prevent acute toxicity.
4. Use unwaxed dental floss to push the material between teeth.
5. Following treatment ask the patient to expectorate several times.
6. Instruct the patient not eat or drink for 30 minutes.
16. Aqueous solutions
Sodium fluoride (NaF).
• These materials are available in form of powder, solution or gel.
• The concentration of sodium fluoride is 2%.
• 9,200 ppm of available fluoride.
• 29% effective in caries reduction.
• These agents have basic PH; chemically stable when stored in plastic or polythene containers, if it is stored in
glass container the fluoride ion of prepared solution can react with silica of glass forming SiF2 (silicon
fluoride). Hence reducing it is anti caries action.
• A flavoring and sweetening agents can be added.
• These materials are not irritant to the gingival, and do not cause discoloration to teeth.
Application of sodium fluoride (Knutson technique)
• Knutson conclude that maximum reduction in caries from application of 2% aqueous NaF that a series of 4-
weekly application intervals at ages of 3, 7, 10, 13 years to coincide with the eruption of teeth (primary and
permanent).
17. • Advantages:
1. Relatively stable when stored in plastic containers.
2. Taste is acceptable
3. Non irritating to gingiva, and does not cause discoloration of tooth structures.
• Disadvantages:
Patient has to make four visits in relatively short period of time.
Stannous fluoride SnF2.
It contains cation (stannous) and anion (fluoride) both react with enamel surface forming calcium fluoride, stannous
fluoroapetite and hydrated tin oxide.
• 8%SnF2 is used
• 2.4-2.8 PH
• 19,500 ppm f available fluoride
• 32% effective in caries reduction.
Method of preparation(Mahler’s technique).
• The solution has to be freshly prepared as they are not stable. It can be prepared by dissolving 0.8 gm of powder in
10 ml of distilled water. The solution is acidic, with a PH of 2.8 the left over solution should be discarded after
application.
• Recommended Schedule: a six monthly interval treatment Schedule is advised.
18. Advantages:
1. Rapid penetration of fluoride to the deeper layer of enamel.
2. Highly insoluble tin fluorophosphates complex form on the enamel surface that acts as protective
layer for the enamel decay
Disadvantages:
1. Unstable in aqueous solution and undergoes rapid oxidation so should be prepared fresh for each
patient.
2. It is highly acidic in nature (PH2.2-2.3)
3. It has metallic taste which as unacceptable t most of the children and patient.
4. It is may cause gingival irritation particularly to dehydrated and diseased gingival tissues.
5. SnF2 produce discoloration of hypo calcified area of teeth. 6.It will produce staining on the
margins of restorations.
19. Fluoride gels and foams contain a high concentration of fluoride, typically up to 12.3 mg fluoride.
Acidulated Phosphate Fluoride
• 1.23% is used
• 12,300 ppm of available fluoride >3.0 pH
• 28% effective in caries reduction reduction [Brudevolds Solution]
• This is available as either as a solution or gel. Both are stable
Advantages:
• It is stable when stored in a plastic container.
• No staining of teeth.
• Gels can self-applied.
• Cheap
Disadvantages:
• Cannot be stored in glass container because it may remove minerals from the glass [etch].
• Repeated exposure of porcelain or composite restorations to APF can lead to loss of material leading to
surface roughening.
• It has an acidic taste.
• Repeated application necessitates the use of suction, limiting its use in field programs.
Fluoride Gels
20. Fluoride Vanishes
Fluoridated varnishes were introduced into the market in the 1960s, and are intended for professional
application only.
The main advantages of varnishes are:
• The prolonged contact time between fluoride and the tooth surfaces (increases fluoride uptake by
dental hard tissues, as well as the formation of CaF2 reservoirs).
• The possibility of using very small amounts of the product (a thin layer).
These products are much more concentrated than gels, with typical concentrations of 22,600 ppm
fluoride(in NaF varnishes) 7,000 ppm fluoride (in difluorosilane varnishes).
Indication of use:
• High risk group.
• Initial caries even for children under 6 years of age as can be applied on the affected surface only.
• Highly indicated for sensitive teeth.
• Root caries.
Despite having higher fluoride concentrations, varnishes can be regarded as a safer option when compared
to gels, due to the small amount used during application.
Fluoride concentrations in plasma and urine of children were reported to be lower than toxic levels after
the application of a fluoride varnish
21. Fluoride Prophylactic Paste
The major functions of prophylactic paste are:
1. To clean the tooth surface through the removal of all exogenous deposits.
2. Polish the dental hard tissues, including restorations.
• Prophylactic paste contains abrasive particles which abrade the deposits and debris from tooth surface.
Studies have shown that their use alone cannot be considered as an effective cariostatic method.
If prophylaxis is required for periodontal reasonthen fluoride prophylactic paste is recommended, as it may
help replenish the minerals that abraded during polishing