THE SCIENTIFIC BASIS FOR THE MODELLING OF CARIES PREVENTIVE STRATEGIES
Abstract
The decline in dental caries in many industrialised countries has prompted a reassessment
of preventive strategies for dental caries. Although methods to prevent
dental caries are well established, few data exist on defining the most appropriate
combination of preventive methods to be used for differing levels of dental caries.
Texts that do outline preventive methods do not make recommendations on the
dental caries conditions under which they should be used. The most popular
approach is the identification of individuals or groups at high risk.
This research aimed to formulate a basis for strategic approaches for the
prevention of dental caries in children based on the distribution of dental caries in
the population at different caries severity levels. The objectives were to analyse
the shapes of distributions and patterns of distribution of caries both within child
populations and in individuals at differing severity levels and factors, such as
presence or absence of water fluoridation, associated with the distributions.
Using Rose's concepts on preventive strategies, approaches to the prevention of
caries were developed based on the analyses.
The study was divided into three phases. First, both the incremental and
distributive properties of dental caries were analysed using the longitudinal United
States National Preventive Dentistry Demonstration Programme's data set. The
results were subsequently tested using data from both the British Association for
the Study of Community Dentistry's national programme in the United Kingdom
and from a study carried out by the University of Wales and Walsall Health
Authority. Secondly, the intra-oral distribution of caries, by tooth type and sites
on the teeth, was analysed to provide the scientific basis for the identification of
the differing components of a preventive package. The third phase developed the
findings from the first two phases to form the basis for strategy component
selection at differing levels of caries.
Results indicate that standard relationships exist between the distribution of dental
caries within populations and in individuals and that the risk of caries increments
will affect the strategic approach. Knowing the DMF provides information on the
prevalence and frequency distribution of caries, the variance, the teeth affected
and the sites on the affected teeth that will be carious. There is a relationship
between the mean caries score of a population and the prevalence of caries within
a population which is independent of water fluoride levels. Furthermore, the
distributive properties indicate that a small decrease in the risk for a whole
population has a greater overall impact on total caries increment than a large
decrease in high risk individuals. There is a hierarchy of susceptibility to caries
within the mouth which is tooth and tooth site specific. The hierarchy is not
linear, certain sites are grouped. This size of the grouping varies. At low levels of
caries the groupings are smaller than at high levels of disease. A reduction in the
attack intensity which benefited the groupings at higher levels of disease would
lead to substantial savings in cavitated sites.
The findings suggest that the adoption of a policy for prevention should be
determined by the caries level within the child population and that the hierarchical
development should affect the choice of components for any preventive strategy.
At low levels of caries, only a relatively low percentage of people would benefit
from a population based fissure sealant strategy, whilst at high disease levels
substantial numbers of a given population will develop approximal lesions in
those teeth which would be sealed. Fluoride reduces the overall attack intensity
and is not site type specific in its action. Current shortfalls in knowledge relating
to fluoride regimes prevent their impact from being modelled accurately.
Authors
Batchelor, Paul AnthonyCollections
- Theses [4235]