[History of fluoride prevention: successes and problems (literature review)].

Fluoride prevention has a significant role in complex caries prevention, together with the appropriate diet and oral hygiene. The aim of the present review is--considering mainly the public health aspects--to give information on changes of the methods of fluoride prevention, and the changing views on pathomechanisms, as well as statements in the course of the last 50 years, based on present scientific evidence. The first great breakthrough in caries prevention was the introduction of water fluoridation between 1945-1950 in the USA and Canada. The measure was adopted in other countries and resulted in significant caries reduction. In the fifties and sixties fluoride tablets were widely used in many countries and brought good results, mainly in well-controlled smaller communities. Salt fluoridation has been initiated in Switzerland in 1955, and introduced in numerous countries in the eighties. The concept of a strong protective systemic effect of fluorides in the early eighties gave place to ideas on mainly topical effects, playing a decisive role in toothpastes, gels, acting topically on the enamel of the erupted teeth. Therefore many water fluoridation projects, mainly in Central- and Eastern Europe--where the prevalence of dental caries is still very high--were cancelled after 1990. Tablet fluoridation became questionable due to the fear of the possibility of dental fluorosis. Recent scientific views, however, confirmed a weak pre-, and peri-eruptive, as well as a strong posteruptive effect of systemically applied fluorides. In countries where caries prevalence is high, but the majority of the population cannot afford fluoridated toothpastes due to low socio-economic conditions, the introduction and extension of salt fluoridation to the whole population is well founded and recommended from a public health view.