THE FACTS ABOUT THE LEVELS OF DENTAL DISEASE IN IRELAND TODAY
Levels of Dental Decay
Between 1979/80, the most comprehensive epidemiological and sociological study of dental disease ever undertaken or likely to be undertaken in this country, was completed with the collaboration of the World Health Organization (WHO). The study, known generally as ‘The International Collaborative Study of Dental Manpower Systems,’ was undertaken in 10 countries, — Australia, New Zealand, Japan, Federal Republic of Germany, USA, Norway, Canada, German Democratic Republic, Poland and Ireland.
In summary, the study revealed that there were two rather special features about dental health in Ireland.
Firstly, “that Ireland belongs to a select group of only 6 countries which have compulsory fluoridation legislation and, secondly, that there is excellent information on dental disease in Ireland over the last 23 years”.
The findings of the study revealed that in children of 8 -9 years of age, Irish children had the second lowest level of dental decay in the countries studied. Only 8 -9 year old USA children had a fractionally lower level of dental decay than the Irish. In comparison. 8 -9 year old Norwegian children had three times the amount of dental decay as their Irish counterparts. While in most of the other countries, 8 - 9 year old children had twice as high a level of dental decay as the Irish.
Significantly, it was found that 8 - 9 year old children in Ireland in 1980 had less than half of the dental decay level than had existed in similarly aged Irish children in 1961. Even more significant was the finding that almost 50% of the Irish children in 1980 had no decay at all of their permanent teeth, compared with only 14% in 1961.
Where 13 - 14 year old adolsecents were concerned again the Irish were second to the USA sample in having the lowest levels of tooth decay. Yet again, Norwegian 13 - 14 year olds had three times the levels of dental decay of the Irish, while in most of the other countries, adolescents had twice as high a level of dental decay as the Irish.
The findings of two other Irish studies on the level of dental decay in 5 year old and 11 year old children, undertaken in Limerick and in Waterford at about the same time (1980/81) displayed an even more substantial decrease in the level of dental decay than had existed in these counties in 1961/62. Once again almost 50% of the children had no decayed teeth.
As recently as 1984, a National Survey of Children’s Dental Health was conducted on behalf of the Minister for Health by University College, Cork. The principal aims of the survey were:
(a)to measure the effectiveness of water fluoridation
(b)to estimate the changes in the levels of dental caries in Irish schoolchildren between 1961/63 and 1984
(c)to measure the levels of enamel opacities including fluorosis and other developmental defects in Irish schoolchildren in 1984.
Random samples of 5-, 8-, 12-, and 15- year olds were examined.
The findings indicated that:
“It is clear that, overall, in the past 20 years there has been a major decline in the prevalence of caries especially in younger children and in those who have been residents of fluoridated communities. For example, in Cork, children whose average age was 5.0 years, the mean DMFT (Decayed, Missing and Filled Teeth) in 1961 was 6.2 (Table 8). In 1984 the corresponding figures for subjects who had some exposure to fluoridation was 2.4, a decline of 61 per cent. The DMFT of 5 year olds in Cork in 1984 who had no known exposure to fluoridated water supplies was 4.3, a decline of 31 per cent.
In older children the decline in the past 20 years in not as marked. For example, in Galway, children with an average age of 12 years (Table 10) the mean DMFT in 1962 was 4.4.. In 1984 the corresponding figures for children in the non-fluoridated and fluoridated groups was 3.0 and 2.6 representing declines of 32 and 41 per cent respectively. For the same age group the corresponding percentage declines in Kerry were 43 and 23 per cent respectively”.
BASED ON THE FINDINGS FROM THE IRISH STUDIES THE WORLD HEALTH ORGANIZATION HAS RECENTLY PREDICTED THAT BY 1990 THE LEVEL OF DENTAL DECAY IN 13 TO 14 YEAR OLDS IN IRELAND WILL HAVE FALLEN BY ALMOST 50% BELOW THE LEVELS STATED FOR 1980. THIS FURTHER REDUCTION WILL REPRESENT A FALL OF ALMOST 75% IN DENTAL DECAY LEVELS COMPARED WITH THE LEVELS IN IRELAND IN 1961.
THE PREDICTED FALL IN THE LEVELS OF TOOTH DECAY IN YOUNGER AGE GROUPS IS COMPARABLE.
The level of experience of dental decay in 35 -44 year olds - the oldest group of the three age groups in the major international study —— was very high in all of the countries, with the exception of Japan and the German Democratic Republic. Where Ireland is concerned, it must be pointed out that this age group did not have the benefit of water fluoridation and other preventive measures, both environmental and social, during their childhood and adolescence. They, therefore, reflect a bygone age of dental disease in Ireland.
GUM DISEASE (PERIODONTAL DISEASE)
In general, and contrary to a long held belief by the dental profession, WHO has also recently established that periodontal disease (serious gum disease) is not a major cause of tooth loss, whereas dental decay is.
In the 10 countries involved in the major international study, referred to previously, Ireland displayed the lowest level of mild gum disease (gingivitis) and of advanced periodontal disease in 35 - 44 year olds. In this context, the WHO analysis stated that the level of periodontal disease in Ireland was —— “ very low compared with other industrialised populations”.
THE NEED FOR ORTHODONTIC TREATMENT
While the WHO analysis states that —— “there is at present a general lack of international consensus as to which traits or combination of traits of malocclusion, or ‘Crowded’ teeth, need orthodontic care” —— on the basis of the criteria used in the major international study, Ireland ranked with Poland in having the highest percentage of children needing orthodontic care.
At the other end of the scale, Ireland again ranked with Poland in providing the least amount of orthodontic treatment relative to the needs of the community.
In terms of the amount of orthodontic treatment provided by each of the 10 countries however, Ireland conforms to the average.
A disturbing phenomenon, common to all countries including Ireland, emerged from the study findings, namely, the relatively high proportion of courses of orthodontic treatment which failed to be completed —— invariably because of a lack of commitment of the children and their parents to the treatment regimen.
The percentage of persons in the 35 -44 year olds who were edentulous, that is, who had lost all of their natural teeth, was lowest in Japan (0%) and highest in New Zealand (30%). Recently the percentage in New Zealand has fallen to 16%.
The percentage of persons in the 35 - 44 year olds in Ireland who had lost all of their natural teeth was 7%. In the USA, Canada and Australia the level was around 12%. Apart from Japan, only the Federal Republic of Germany (1.6%) and Norway (5%) had a lower level of edentulousness than the Irish.
As dental decay is the major cause of tooth loss and as the levels of dental decay in adolescents in Ireland is already seen to be extremely low and reducing further, there is every reason to expect that the level of edentulousness in Ireland will fall rapidly. This anticipated decrease in the level of edentulousness amongst the Irish is undoubtedly being accelerated by the already evident change in social attitudes towards tooth loss.