There are various modes of administration of fluoride : It can be given systemically or applied topically for preventive effect. Systemic administration, in the form of community water fluoridation is the most effective, efficient and economical measure for the prevention of dental caries. But, fluoridated water is available to only a few percent of the population, hence, alternative methods are required.
Also, it was found from many epidemiological studies that erupted teeth benefited substantially from exposure to fluoride, and the amount of fluoride in tooth enamel could be increased by applying fluoride topically to tooth surfaces.
Rationale
- The enamel is not completely calcified at the time of tooth eruption and enamel calcification continues during the post eruptive period, approximately 2 years (enamel maturation period).
- During this period, fluoride deposition takes place in the superficial layer of enamel. This fluoride is derived from saliva and also from exposure of teeth to fluoride-containing water and food.
- Thus, most of fluoride incorporation into enamel occurs during pre-eruptive period (by systemic fluoride) and the post eruptive period of enamel maturation (topical fluoride).
Systemic Fluorides
These are ingested and delivered to the oral cavity via the blood stream, during the development of dentition (pre-eruptively). The objective is to administer the fluoride during pre-eruptive phase, so that it is absorbed into the body and laid down in forming tooth mineral.
Methods
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Community water fluoridation
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Salt fluoridation.
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School water fluoridation.
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Milk fluoridation
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Dietary fluoride supplements :
- Fluoride drops, tablets or lozenges.
- Sustained release devices.
Advantages
- Cost effective and cheaper.
- No motivation or behavioural changes necessary.
- Usually lower concentrations of fluorides are used.
- Recommended in general for the whole population and mainly for prophylactic benefit against dental caries.
- Effect lasts longer and throughout life, as fluoride gets incorporated in the tooth structure during developing stage.
Disadvantages
- Political or emotional objections to water additives.
- Possibility of mild to moderate fluorosis, if excess amount of fluoride is ingested inadvertently (more than optimal level of 1 ppm).
Topical Fluorides
It involves the topical application of relatively large concentrations of fluoride to the newly erupted tooth surface, since, as the tooth is porous and immature, it acquires fluoride rapidly and makes enamel more resistant to dental caries.
Methods
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Professionally applied :
- Sodium fluoride preparation.
- Stannous fluoride preparation.
- Acidulated phosphate fluoride (APF).
- Fluoride varnish.
- Fluoride impregnated floss and prophylactic paste.
- Fluoride containing dental materials and devices
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Self applied :
- Fluoride dentifrices, mouth rinses, gels.
- Fluoride toothpicks, floss, chewing gums.
Advantages
- Available only to people who desire it, no community objection.
- Does not cause fluorosis.
- Cariostatic for people of all ages.
Disadvantages
- Per capita cost is higher compared to water fluoridation, as they have to be applied professionally (sometimes can be used by patients themselves at home e.g, fluoride dentifrices, fluoride mouth rinse and fluoride gels).
- Patient compliance required in case of home applications such as dentifrices and mouth rinse.
- Use of more concentrated products can cause short-term side effects like nausea immediately after use.
- Requires repeated application, as the effects are seen only for shorter duration of time (since the topical fluoride is lost from tooth surface after application).
References
- C. M. Marya - A Textbook of Public Health Dentistry, Jaypee Brothers Medical Publishers (P) Ltd (2011). https://amzn.to/3SHP36G
- S. S. Hiremath - Textbook of Public Health Dentistry, Elsevier India (2016). https://amzn.to/49mh2jw
- The image used is available in the public domain (Source: Wikimedia Commons).
*This article is an excerpt from the above mentioned books and Medical Sutras does not make any ownership and affiliation claims.