Modelos explicativos da cárie dentária: do organicista ao ecossistêmico / Explanatory models for dental caries: from the organismic to ecosystemic model

Introdução: A cárie dentária é um problema de saúde pública e sua história, nos seus aspectos etiopatogênicos, tem sido objeto de muitas teorias. A explicação originalmente microbiana para a doença cárie, evidenciada há mais de um século, foi o ponto de partida para o delineamento do pensamento científico: bactéria como etiologia da doença. No entanto, esse pensamento científico sofreu transformações conforme os diferentes momentos históricos e suas realidades explicativas. Objetivo: O objetivo deste trabalho foi descrever, por meio da revisão de literatura, os diferentes modelos explicativos da cárie dentária e o importante papel que esses assumem na ciência ao representar um novo paradigma dominante. Resultados: Os modelos teóricos explicativos da cárie foram classificados em: organicista, social e ecossistêmico. No modelo organicista, foram incluídos a teoria químico parasitária, a Tríade de Keyes e o modelo de Newbrun. Ao longo do tempo surgiram novos modelos explicativos para a cárie dentária, o social e o ecossistêmico, com dimensões coletiva, social e histórica. Os novos modelos são embasados na teoria de que a cárie tem ataque desigual na população e não decorre apenas de variações biológicas individuais, mas, também, das diferenças sociais que caracterizam as pessoas no meio em que se inserem. Conclusão: O modelo explicativo da cárie dentária sofreu modificações ao longo do tempo, do unicausal para o multicausal e do individual para o populacional, contudo velhos e novos paradigmas coexistem na atualidade. A concepção estritamente biológica, na explicação da cárie, não respeita as características culturais de uma determinada população.

Introduction: Dental caries is a public health problem and its history, in its etiopathogenesis, has been the subject of several theories. The original microbial explanation for caries disease, which dates back over one hundred years ago, was the starting point for outlining the scientific though of bacteria as the etiological agent of this disease. However, this scientific thought shifted according to the different historical moments and their explanatory realities. Objective: The aim of this study was to describe, by a literature review, the different explanatory models for dental caries and the important role that these models play on science as they represent a new dominant paradigm. Results: The theoretical-explanatory models of caries disease were classified as organismic, social and ecosystemic. The chemical-parasitic theory, the Keyes's Triad and the Newbrun's model were included in the organismic model. New explanatory models for dental caries were proposed over time: the social and the ecosystemic models, with collective, social and historical dimensions. These new models are based on the theory that dental caries affects the population in an uneven basis, and that it does results only from individual biological variations, but also from the social differences that characterize people in the environment in which they belong. Conclusion: The explanatory model for dental caries has shifted along the time, from a single-cause to a multifactorial, and from an individual to a population-based disease. Nevertheless, old and new paradigms coexist in these days. The strictly biological conception to explain caries disease does not take into consideration the cultural characteristics of a given population.

Accuracy of the simplified Thylstrup & Fejerskov index in rural communities with endemic fluorosis.

The aim of the present study was to compare the values of the Thylstrup & Fejerskov Index (TF index) for the determination of the prevalence of dental fluorosis using either all teeth (gold standard) or six upper anterior teeth (simplified TF index). The sample was made up of 396 individuals aged six to 22 years from three Brazilian cities with endemic fluorosis caused by the ingestion of water with high fluoride concentration. The prevalence of dental fluorosis was evaluated by a single trained examiner with excellent intraexaminer agreement (kappa = 0.95). Intraexaminer reproducibilities were calculated at tooth level. Sensitivity, specificity, positive and negative predictive values of the simplified TF compared to gold standard were 90.6 (95%CI: 86.6 to 93.6), 100 (95%CI: 95.3 to 100), 100 (95%CI: 98.3 to 100) and 77.5 (95%CI: 69.8 to 83.5), respectively. The ROC value was 0.953 (95%CI: 0.933 to 0.973). The simplified TF index proved suitable for determining the prevalence of dental fluorosis in regions with endemic fluorosis caused by the ingestion of water with high concentrations of fluoride.