Early Childhood Caries: Prevalence, Risk Factors, and Prevention

Although substantial epidemiologic evidence links Streptococcus mutans to caries, the pathobiology of caries may involve more complex communities of bacterial species. Molecular methods for bacterial identification and enumeration now make it possible to more precisely study the microbiota associated with dental caries. The purpose of this study was to compare the bacteria found in early childhood caries (ECC) to those found in caries-free children by using molecular identification methods. Cloning and sequencing of bacterial 16S ribosomal DNAs from a healthy subject and a subject with ECC were used for identification of novel species or uncultivated phylotypes and species not previously associated with dental caries. Ten novel phylotypes were identified. A number of species or phylotypes that may play a role in health or disease were identified and warrant further investigation. In addition, quantitative measurements for 23 previously known bacterial species or species groups were obtained by a reverse capture checkerboard assay for 30 subjects with caries and 30 healthy controls. Significant differences were observed for nine species: S. sanguinis was associated with health and, in order of decreasing cell numbers, Actinomyces gerencseriae, Bifidobacterium, S. mutans, Veillonella, S. salivarius, S. constellatus, S. parasanguinis, and Lactobacillus fermentum were associated with caries. These data suggest that A. gerencseriae and other Actinomyces species may play an important role in caries initiation and that a novel Bifidobacterium may be a major pathogen in deep caries. Further investigation could lead to the identification of targets for biological interventions in the caries process and thereby contribute to improved prevention of and treatment for this significant public health problem.

To conduct a systematic review of the literature on risk factors for dental caries in deciduous teeth of children aged six years and under, to give a scientific framework for the international collaborative studies on inequalities in childhood caries. Accepted guidelines were followed. Studies were identified by electronic searching and reviewed on the basis of key words, title and abstract by two reviewers to assess whether inclusion criteria were met. Copies of all articles were obtained and assessed for quality according to the study design. 1029 papers were identified from the electronic search, 260 met the prima facie inclusion criteria. 183 were excluded once full copies of these papers were obtained. Of the 77 studies included, 43 were cross sectional, 19 cohort studies, 8 case control studies and 7 interventional studies. Few obtained the highest quality scores. 106 risk factors were significantly related to the prevalence or incidence of caries. There is a shortage of high quality studies using the optimum study design, i.e. a longitudinal study. The evidence suggests that children are most likely to develop caries if Streptococcus Muttans is acquired at an early age, although this may be partly compensated by other factors such as good oral hygiene and a non-cariogenic diet. Diet and oral hygiene may interact so that if there is a balance of 'good' habits by way of maintaining good plaque control and 'bad' habits by way of having a cariogenic diet, the development of caries may be controlled.

The persistent and universal nature of oral health inequalities presents a significant challenge to oral health policy makers. Inequalities in oral health mirror those in general health. The universal social gradient in both general and oral health highlights the underlying influence of psychosocial, economic, environmental and political determinants. The dominant preventive approach in dentistry, i.e. narrowly focusing on changing the behaviours of high-risk individuals, has failed to effectively reduce oral health inequalities, and may indeed have increased the oral health equity gap. A conceptual shift is needed away from this biomedical/behavioural 'downstream' approach, to one addressing the 'upstream' underlying social determinants of population oral health. Failure to change our preventive approach is a dereliction of ethical and scientific integrity. A range of complementary public health actions may be implemented at local, national and international levels to promote sustainable oral health improvements and reduce inequalities. The aim of this article is to stimulate discussion and debate on the future development of oral health improvement strategies.