Caries prophylaxis with fluorides
Dental caries is a major world-wide health problem, which, apart from its effects on oral and dental health, carries an important economic load (costs of dental care, of partial and full prostheses etc.). However, it is one of the few diseases in man which can be avoided by the use of simple procedures. The basic measures for prevention of caries are based on the causes of the disorder. There are four main prophylactic strategies for the avoidance of caries:
Nutrition: consumption of foodstuffs with a low sugar content will reduce the risk of development of caries.
Oral hygiene: brushing the teeth after every meal, and careful daily removal of coatings on the teeth, particularly in the interdental areas, will help maintain healthy teeth.
Early detection and treatment: regular visits to the dentist ensure that any dental disorders will be detected at an early stage.
Fluoridation: in the alternation between de- and remineralisation processes, fluorides have a regulatory function, as they tip the equilibrium in favour of remineralisation. If fluorides are present in sufficient concentrations in the saliva and in the plaque fluids around the teeth, the natural rate of remineralisation is stimulated, while demineralisation is inhibited. Fluorides thus accelerate the remineralisation processes.
There are two methods of fluoride administration in the prevention of caries:
Fluoride is administered to the body as a whole by systemic fluoridation. Due to secretion of fluoride-enriched saliva and a limited local effect after oral uptake of fluoride, there is an increase in fluoride concentrations in the mouth. The methods used for systemic fluoridation include fluoridation of drinking water and of table salt and use of fluoride tablets.
Fluoride is administered directly to the mouth in topical fluoridation: use of fluoridated dental and oral care products results in an increase in fluoride levels in saliva and plaque and on the surface of the teeth. The increased use of fluoridated toothpastes over the last few years has resulted in a marked fall in the incidence of caries. Topical fluoridation should thus be seen as a major factor in caries prophylaxis.
The mechanism of action of fluoride in caries prophylaxis
Fluoride reduces the acid solubility of dental enamel, stimulates the remineralisation of enamel, and reduces acid production in plaque. Its anticariogenic effects are mainly attributable to two mechanisms:
If fluoride ions are available in the neighbourhood of the dental enamel during an acid attack, fluoroapatite is incorporated, during the remineralisation phase, at pH levels at which hydroxyapatite still dissolves. The remineralisation range for dental enamel is thus extended by fluoride ions, and the demineralisation range, as a consequence, is reduced.
When dental and oral care products containing fluoride are used, calcium fluoride is formed in the mouth, and this acts as a pH-controlled fluoride reservoir. During acid attacks it breaks down to release fluoride ions, which then stimulate natural remineralisation in the form of fluoroapatite.
At high concentrations, fluoride reduces bacterial production of acids, thus reducing the risk of caries. It is a matter of controversy whether this effect is relevant in vivo.
Amine fluorides such as olaflur and dectaflur are used in all elmex products and have a slightly acidic pH. For this reason, fluoride ions can combine rapidly with the calcium in dental enamel to form calcium fluoride. The surfactant characteristics of amine fluorides also promote homogeneous distribution of the calcium fluoride globules. Calcium fluoride formed during exposure to amine fluoride is thus characterized by:
The elmex toothpastes and the elmex dental rinse are CARIES PROTECTION products for use in daily oral and dental care. The high concentrated medicinal products elmex gel and elmex fluid are designed for intensive caries prophylaxis in groups which are particularly at risk of developing caries.