PREVENTION OF DENTAL CARIES THROUGH THE EFFECTIVE USE OF FLUORIDE – THE PUBLIC HEALTH APPROACH water engineers , and a favorable public opinion are essential factors 14 , 34 , 59 . WHO has issued a publication on inadequate or excess fluoride prepared within the context of preventing disease through healthy environments ; this document focuses on the sources of exposure to fluoride and health effects 60 . Dental enamel fluorosis should be monitored periodically to detect increases in or higher-than-acceptable levels of fluorosis . Action , such as adjusting intake of fluoride from water , salt , milk or other sources , should be taken when the prevalence of fluorosis is found to be excessive . It is highly recommended to calculate the community fluorosis index ( CFI ) using data generated from examinations of renal excretion undertaken by calibrated examiners as part of epidemiological studies to assess whether occurrence of unsightly fluorosis constitutes a public health problem warranting increasing consideration . WHO produced in 2014 a manual on the assessment of renal fluoride excretion in community prevention programmes for oral health 61 . This manual informs on practical procedures in measuring exposure to fluoride from existing fluoridation programmes . It complements the WHO “ Oral Health Surveys – Basic Methods 2013 ” 62 which provides guidelines for obtaining epidemiological information about the population level of dental caries and the prevalence of enamel fluorosis . Salt fluoridation may be relevant to countries where the technical facilities for water fluoridation are not available . It is required that salt production and distribution can be controlled . Salt fluoridation is an effective alternative that has the advantage of allowing consumer choice ; this may be important in certain countries or cultures . An overview of some practical aspects relating to the implementation of salt fluoridation programmes has been published 39 , 40 . Milk fluoridation is particularly used for promoting oral health in children . WHO published a comprehensive manual 48 on milk fluoridation which highlights the rationality of milk as a vehicle for the administration of fluoride ; the manual details the biological basis , the opportunities for integration with other national or community programmes on diet and nutrition , development of community and school health programmes , challenges in practical implementation , and monitoring and evaluation of programmes . The evidence on the use of milk fluoridation is outlined in this manual and further supported by country experiences . A global report has revealed that the school is a unique platform for fluoride administration , particularly when programmes are organized according to the WHO Health Promoting Schools Project 63 , 64 . WHO convened an Expert Committee in 1993 to provide authoritative information about the role of fluoride in the promotion of oral health throughout the world 59 . In 2016 , a similar group of experts published an update of the research on fluoride and oral health and the findings are reported in a special issue of the journal Community Dental
Health 34 . It reviews the effect of fluoride from biological , clinical and public health perspectives . The document focuses on the presence of fluoride in the environment ; fluoride metabolism and excretion ; fluoride in teeth and bone ; biomarkers of fluoride exposure ; dental caries prevention and enamel fluorosis ; fluoridated drinking water , salt and milk ; topical use of fluoride , and fluoridecontaining toothpaste . Based on the modern conception of evidence for public health the report emphasizes the effectiveness and appropriateness of different fluoride application forms in communities and specifies the practical impact of implementation of combined administration of fluoride . In addition , this publication summarizes the experiences from the use of fluoride around the globe . Such update information is highly relevant to countries which are in process of introducing fluoride programmes or to those countries engaged in adjustment of programmes .
5 . The need for further research Continuous research is vital to advance the use of fluoride for oral health in countries . It is important to maintain and foster a programme of public health research that might seek to :
• update our information on the cost-effectiveness and cost-benefit of water , salt and milk fluoridation against a background of the now widespread use of fluoride-containing toothpastes ;
• continue to develop and update our knowledge of the health effects of ingested fluoride ;
• further develop affordable techniques for the removal of fluoride from the public water supply in communities where natural concentrations of fluoride are above the guideline value of 1.5 mg / l set by WHO 65 ;
• better understand the public perception of dental enamel fluorosis and , increment efforts to educate the community so that it is well understood that enamel fluorosis is not a disease and that mild forms are preferable to the devastating effects of dental caries ; and
• evaluate the effects of the introduction of affordable fluoride-containing toothpastes on purchase and use by the public . Research on the prevention of dental caries through the use of fluoride is urgently needed in low and middle income countries . It is well recognized from research undertaken in high income countries that population wide automatic fluoridation measures are most effective and equitable strategies for the prevention of dental caries ; however , it remains to clarify to what extent the implementation of fluoridation programmes is possible in low and middle income countries and whether similar health results may be obtained . In addition , the social inequalities in dental caries prevalence are substantial in all countries and further evidence is needed on how to break the gap between rich and poor population groups through effective use of fluoride .
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