Dental health 231 The main inhibiting factor has been a small and vociferous minority, who oppose fluoridation on the grounds that it is a hazard to health and that it is unethical to tamper with water supplies. Two years ago, the Royal College of Physicians published a report of a Committee which had spent nearly 3 years inquiring into possible health hazards. The unequivocal conclusion was that fluoridation is safe and constitutes no hazard. Regarding the ethical aspects, this is very much an emotional and personal view my view is that it is unethical to withhold this proven health measure. Fluoridafion exerts its effect systemically, the fluoride ions being absorbed intestinally and, via the bloodstream, becoming incorporated into the crystalline structure of the tooth enamel during the development period. In this way the proportion of fluorapatite is increased thus decreasing the solubility of the enamel acids. Tablets containing fluoride are believed to be just as effective but, their regular daily ingestion for the first 14 or so years of life does require intense dedication and motivation. Tablets provide an individual preventive measure but water fluorida- tion includes the community as a whole and requires no individual effort or responsibility. Topical fluorides using dentifrice, or mouthwash as the vehicle are becoming in- creasingly popular. In fact, over 90• of toothpaste sold in the U.K. contains either sodium monofluorophosphate or stannous fluoride. The actual amount of paste sold however, suggests that large numbers of the population do not use toothpaste at all. Almost all these toothpastes have been tested by means of a traditional 3 year Clinical Trial and shown to be effective in reducing decay. Taking into account the natural history of the decay process and the limited duration of the trials, it should surprise no one that the absolute values of the reduction in decay are somwhat small. However, there can be no doubt that regular and conscientious use of a fluoride dentifrice, both in terms of specific fluoride effect and the plaque removal function, is an important feature of any preventive programme. As far as mouthwashes are concerned, the early studies carried out in Sweden, indicated that fluoride mouthwashes used as infrequently as at monthly intervals, caused a significant and clinically relevant reduction in the number of fillings required. In recent years an increasing number of practitioners have been providing 'preventive packages' which comprise dental health education, dietary advice, topical fluorides including dentifrices. Whilst we support wholeheartedly this approach and the philosophy behind it, we are very doubtful of the need for multi-topical fluoride treatments. Our own work in recent years has been concerned with this matter and we have already published the report of one study and the second is about to appear very soon. The first study was carried out in Croydon and was designed to determine the effect on 2-year decay increments of supervised daily use at school of an acidulated phosphate fluoride rinse and a sodium monofluorophosphate toothpaste used singly and in com- bination. Statistically significant reductions in 2-year caries increments were observed in all three experimental groups, i.e. fluoride rinse alone fluoride dentifrice alone and both together- when compared with the control. However, there were no significant differences between treatment groups. Our second study was carried out on the Isle of Wight and in London and was designed to test the decay prevention of twice per year professional applications of APF gel and the unsupervised home use of a monofluorophosphate-calcium carbonate based dentifrice used either singly or in combination. The findings were similar to the Croydon Study.

232 M. N. Naylor The APF gel and flouride paste used singly or together, produced significant reductions in decay but, as in Croydon, there was no significant difference between treatment groups. From these studies it would certainly seem that little or no advantage is to be gained from a multiple topical fluoride approach. Since fluorides, whether systemically or topically applied exert their maximum effect on the smooth non-biting surfaces of the teeth, it would obviously be desirable if some procedure could be devised to protect the biting surfaces. Fissure sealing is one possibility. This notion is not especially new as long ago as the 1920s T.P. Hyatt was advocating the sealing of fissures with amalgam prior to the onset of decay. Hyatt estimated that the chances of a fissure becoming decayed were 2,500 : 1. Whether these odds are valid today it is difficult to say, but it is certainly true that few fissure surfaces escape. It is therefore a reasonable approach to pre-empt the decay and seal the fissure immediately the tooth erupts through the gum. Sealing by means of amalgam which requires a very shallow cavity to be cut, has been superceded by a group of resinous materials which are polymerised in situ either by chemical means or ultra-violet light. Unfortunately, for such sealing to be successful an extremely meticulous technique is needed and a very co-operative subject. It is because of these very precise clinical requirements that the assessments of sealants, both in terms of retention and decay prevention have been so variable. Of course, far worse than losing the sealant, is the situation where the sealant remains in situ but leaks, thus allowing bacteria and sugars to accumulate beneath and start the caries process which can remain undetected for a very long time. Whilst present sealants can be successfully applied to selected patients, we shall have to await the development of material which demand a much less precise technique before sealing can be regarded as a community measure. For many years the notion of elaborating a vaccine against dental diseases has waxed and waned. It is not surprising that, with the relatively recent advances in knowledge of the microbiology of decay and periodontal disease we should see a resurgence of interest in the possibility of developing a human vaccine. Whatever anyone may have read in the tabloid Sunday newspapers, no effective human vaccine is in existence today. There is considerable work in progress in the U.S. and here in the U.K. at the Royal College of Surgeons and at Guy's Hospital Dental School. Primate studies have been most interest- ing, and encouraging. Nevertheless, there are many problems to overcome, not least the problem that these diseases are multi bacterial they are not due to a single organism like the recognised immunisable diseases. Furthermore, if and when a vaccine is developed, it will be necessary to convince the public that the risks associated with vaccination are justified, especially since there are other effective ways of prevention. From what has been said so far, it is clear that good dental health is within the reach of all. The problem is motivation and the creation of the right attitudes. Certainly, in my professional lifetime, which covers the years since the end of World War II, there has been tremendous progress. Undoubtedly, the availability of dental care as part of the NHS has played a great part in this. Other factors of equal importance are the advances in treatment techniques - local anaesthetics, the high speed air-turbine handpiece, low seated, four handed dentistry- are but a few. Advertising of dental products, notably toothpastes on commercial television, have done a superb job in bringing dental health right into the homes of the public. Together these factors have taken much of the fear and pain out of the visit to the dentist.