This document provides an overview of professionally applied topical fluorides for caries prevention. It defines topical fluoride therapy as using high concentrations of fluoride applied locally to tooth surfaces. Common forms discussed include sodium fluoride, stannous fluoride, acidulated phosphate fluoride, and fluoride varnish. Application techniques and mechanisms of action are described for each. Effectiveness is supported by several clinical studies showing reductions in caries increment ranging from 30-66% with topical fluoride use. Contraindications and advantages/disadvantages of each product are also summarized.

1. Professionally applied
topical fluorides
Dr. Shivashankar.K
1st year M.D.S. Department of P.H.D.
Saveetha Dental College.

2. Contents
 Introduction
 Definition
 Indications
 Contraindications
 Rationale
 Technique of application
 Products
 Sodium fluoride
 Stannous fluoride
 Acidulated Phosphate fluoride
 Fluoride varnish
 In-office mouth rinse
 Conclusion

3. Introduction

4. Definition
Topical fluoride therapy refers to the use of systems containing
relatively large, concentrations of fluoride that are applied
locally, or topically, to erupted tooth surfaces to prevent the
formation of dental caries.
Richard. E. Stallard- A Textbook of Preventive Dentistry. 2nd edition.

5. Indications
 Patients who are at high risk for caries on smooth tooth
surfaces
 Patients who are at high risk for caries on root surfaces
 Special patient groups, such as: Orthodontic patients
 Patients undergoing head and neck irradiation
 Patients with decreased salivary flow
 Children whose permanent molars should, but cannot, be
sealed

6. Contraindications
 Patients with low caries risk who reside in communities with
optimal fluoridation

7. Rationale for topical fluoride
 Fluoride concentration of enamel is inversely related to the
prevalence of dental caries (1940- Volker and Colleagues ).
 Keen et al in 1973 showed the relationship between surface
enamel fluoride content and caries prevalence.
 Highest concentration of fluoride occurs at the outermost
portion of the enamel surface(5 to 10 micron), and decreases
towards the dentin (Brudevold et al 1975)

8. Technique of topical application
1. Paint on technique
2. Tray technique

9. Products
 Neutral sodium fluoride solution (NaF)
 Stannous fluoride (SnF2)
 Acidulated phosphate agents
 Varnish
 In office fluoride mouth rinses.

10. Sodium fluoride (2%)
Preparation:
 20 gms NaF dissolved in 1lt of distilled water
 Plastic bottle
Knutson’s technique
 Cleaning and polishing
 Isolated with cotton roll
 Teeth dried
 Paint on with applicator tip
 Dry for 4 min
 Avoid eating, drinking or rinsing for 30 min
 Weekly intervals
Recommended ages
 3,7,11 &13 years, 4 times weekly intervals

11. Mechanism of action
 Sodium fluoride reacts with hydroxyapatite crystals forming
CaF2
 Fluoride concentration – 9000 ppm
 Chocking off- initial rapid reaction followed by reduction in its
rate.
 Thick layer of calcium fluoride interferes with further diffusion
 Calcium fluoride reacts with hydroxyapatite forming
fluoridated hydroxyapatite.
 Less susceptible to caries, stable product.
 Plaque metabolism- anti- enzymatic action.

12. Advantages and disadvantages
ADVANTAGES:
1) Relatively stable, Needs Plastic Containers
2) Well acceptable taste, Non Irritating and no -discoloration
3) Suited for public health programmes
DISADVANTAGES:
4 visits relatively at short period of time .

13.  1940- volker et al invitro study- solublity of enamel is reduced.
 1941- Bibby had done 1st clinical study using a 0.1% aqueous
NaF solution for 7-8 min. 1 year follow-up. 45% caries
increment.
 1942 - Knutson suggested technique which required 4 visits.
 1948- Knutson and galagan 1% aqueous NaF. 4.9-5.8%
reduction.
 1959- Sundvall- Hagland et al studied the effectiveness of
Knutson technique on caries incidence in the deciduous teeth.
.5% reduction in caries increment.

14. STANNOUS FLUORIDE
(STANNOUS FLUORIDE 8%)
PREPARATION………0.8gms in 10ml water
METHOD OF APPLICATION:
 Cleaning and polishing
 Isolated with cotton roll
 Teeth dried
 Paint on with applicator tip
 Teeth kept moist for 4 minutes
 Re-application done for every 15-30 seconds.

15. Mechanism of action
 Tin reacts with enamel forming stannous tri-fluorophosphate
which is more resistant.
 If exposed to air stannous form of tin gets oxidized to stannic
form.
Main end-products:
 Stannous hydroxy phosphate
 Stannous- tri- fluorophosphate
 Calcium tri fluorostannate
 Calcium fluoride

16. Advantages and disadvantages
ADVANTAGES:
Applications required only once per year
DISADVANTAGES:
• Bitter metallic taste, disagreeable taste
• Needs to be freshly prepared for each appointment
• Not stable in solution
• May cause reversible tissue irritation and staining at the margins
of restoration

17.  1957- Muhler et al one application of SnF2 vs 4 application of
SnF2. 21% reduction in caries increment.
 1957-1962 Muhler et al compared 1 application of SnF2 vs
4applications of NaF. 37% less caries increment which is
56% lower than national average.
 1974- Howink et al study among24 pairs of monozygotic
twins. Intervention was given to one group (1% fluoride) and
other group was control (no treatment). The intervention
group showed 37% fewer lesions compared to control group.
 1960- Scott et al. Stannous fluoride forms a coating over
enamel. In-vitro electron microscope study.
 1967- Stannous ions may reduce fluoride uptake.

18. Acidulated phosphate agents
Method of preparation :
 20gms..1litre of (0.1M phosphoric acid)
 added 50% hydrofluoric acid
 pH adjusted to 3 & F Conc. At 1.23%
Recommended Frequency
 Twice a year

19. Application
 Cleaning and polishing
 Isolated with cotton roll
 Teeth dried
 Paint on with applicator tip
 Teeth kept moist for 4 minutes
 Apply for every 30 seconds

20.  1947- Bibby et al low pH high fluoride absorption.
 1963- Brudevold Fluoride concentration in enamel increases
with decrease in pH
 1961- Brudevoldt et al 66% reduction in caries lesion in
children. Bitewing radiograph.
 1963- Brudevold et al . Neutral sodium fluoride vs acidulated
phosphate fluoride. Split mouth trial. APF is 50% more
effective than neutral sodium fluoride.
 1968- Brudevold et al, Cartwright et al. bianual APF vs tap
water. 44-49% reduction in the new DMF

21. OTHER METHODS
 Wax or plastic trays- blotting paper soaked with APF solution
 Gelling agent- methylcellulose or hydroxyethyl cellulose
added and pH adjusted to 4-5.
 Trays- not sure of covering proximal surfaces
 Gel- thixotrophic.

22. APF gel
 Mouth trays should be tried in the patient's mouth
 Upright and suction
 Teeth should be air-dried, cleaning or prophylaxis
 2–2.5 grams per tray or 40% of the tray's volume.
 Upper and lower trays should be inserted separately.
 Fluoride should be applied for 4 minutes, not 1 minute.
 Expectorate for 1–2 minutes after tray removal.
 Patient should not rinse, eat, or drink for at least 30 minutes after the
procedure.

23. 1 minute gel application
Silverstone
 majority of fluoride uptake takes place in first 1 minute after application.
 Reduces gel ingestion.
 Prevent etching of porcelain or composite restoration
Dental Health Education by Christilina.B.DeBiase.

24.  1967- Szwejda et al (1st gel study) no reduction after 1 year
 1968- Brayan et al 45% reduction in DMF after single
application.
 1970- Ingraham et al. APF gel vs APF solution. Gel is 50%
more effective than solution. Limitations: non-homogenous
groups.
 1971- Horowitz and Doyle. APF solution is better than gel.
1100 children of age group 10-12 years

25. A study on APF by Horowitz and Doyle (1971) The
result after 3 years.

26.  1967- Averill et al. 2 years study among 483 children of 7-11
years.
control group- saline- 4.4
2% aqueous NaF- 3.9
4%Stannous Fluoride- 4.1
2% APF- 4.5

27. IN-OFFICE FLUORIDE MOUTH RINSES
 Two-part fluoride rinses are being used more frequently
These rinses consist of two fluorides, APF and stannous
fluoride, which are mixed or used concurrently
 Two-part rinses are marketed as a preventive agent that is
better tolerated than tray applications and reduces fluoride
ingestion.
 Fluoride concentrations are much lower compared with APF
gel (1,500–3,000 ppm vs. 12,300 ppm).
 Second, the risk of ingestion is greater because rinses can
be more easily swallowed.

28. FLUORIDE VARNISH
 The most common types of NaF varnish are Duraphat (2.2%
F) and Fluor Protector (0.1% F).
 The advantage of varnish is its ability to adhere to tooth
surfaces, which prolongs contact time between fluoride and
enamel and improves fluoride uptake into the surface layers
of enamel.

29. Fluoride varnish
Duraphat:
 22600 ppm NaF
 Caries reduction 30-40 % in permanent dentition
 7-44% in primary dentition
Methods
 No isolation as varnish sticks to cotton
 0.5 ml equivalent to 11.3mgF, enough to cover full dentition
 4 mins

30. Fluoride varnish
Fluorprotector:
 Clear polyurethane based products
 Contains silane fluoride 7000ppm
 40% caries reduction
 The recommended dose of 0.5ml contains 3.1mg F
Mechanism of action
Fluoride + hydroxyapaptite =fluorapatite

31.  Remove excess moisture from teeth with a cotton swab, cotton roll, or
air syringe.
 0.5–1 ml of varnish
 thin layer using a disposable brush, or cotton pellet.
 The entire tooth surface must be treated
 Avoid applying varnish to gingival tissues because of the risk of contact
allergies.
 No drying is required after application
 mouth can be closed immediately following treatment.
 Patients can only have fluids or soft foods during the next four hours.
Patients should not brush their teeth for the rest of the day.
Note: Varnish is contraindicated for persons with a history of allergies or
asthma

34.  1987- Shobha, Nandlal et al, A clinical study showed fluoride
varnish was more effective than APF
 1995-Seppa and Co-worker reported the semiannual application of
NaF varnish and APF gel and observed no significant difference
between the two.
 1982- Seppa et al, Duraphat(66% )found to be more effective than
Fluorprotector (49%).

35. Conclusion

36. References
 R. Hawkins, D. Locker and J. Noble; series editor E. J. Kay
prevention. Part 7: professionally applied topical fluorides for
caries prevention. British dental journal volume 195 no. 6
SEPTEMBER 27 2003 p 313-317
 Ole fejerskov, brion A.Burt fluoride in dentistry, 2nd edition,.
 J.J.Murray, et al. Fluorides in caries prevention (3rd edition ),
varghese publishing house.

37. Thank you