Comment

It has long been recognized that within one country people with a lower socio-economic status (SES) enjoy less good health than people with a higher SES. While water fluoridation may exert a levelling effect with respect to the impact of SES on dental caries, it is generally held that SES does impact upon oral health status in any given country. What this study aims to do is to use available nation-by-nation data on SES indicators, on sugar consumption, on tobacco use and on civil strife/instability and to study the impact of these on oral health using available oral health status data (caries, DMFT at 12 years of age; periodontal disease, CPITN-4 at 35-44 years; oral cancer).

The data used was what was available. That this data had not been collected specifically to allow this kind of study does not detract from the study but rather enhances it. However, the data for the dependent and independent variables in the analysis are a mixture of cross-sectional and longitudinal data and some data, such as oral cancer data from low SES countries, is not of the highest order.

Perhaps because of the limitations of oral cancer data, (or perhaps because oral cancer predisposition truly is not impacted upon to the same extent by SES variables as caries at 12 years and periodontal disease in adulthood), SES variables were associated with oral cancer less strongly in this study. The association of SES variables with caries at 12 years old is intermediate but the strongest association with SES is the prevalence of those with CPITN-4 (deep pockets > 5.5 mm). The authors in the discussion dwell on the association between stress and periodontal disease experience. They do not provide a clear conceptual link between SES variables and stress. An American study ¹ has concluded that psychological measures of stress associated with financial strain and distress are significant risk indicators for more severe periodontal disease in adults. If this association holds true in countries outside the USA, perhaps this may explain why SES variables in this study were shown to be so strongly associated with the prevalence of those with periodontal pockets.

This is the first report to show, using nationally generated data, that structural issues within a nation affect that nation's oral health status, particularly periodontal status. This reinforces the contention that any (nationwide) health education endeavour which concentrates purely on behavioural issues, such as improved toothbrushing, is unlikely to be entirely successful in improving a nation's oral health status if the social and SES influences on oral health remain unaltered.