Life-course epidemiology: concepts and theoretical models and its relevance to chronic oral conditions.

Etiological models that predominantly emphasize current adult life styles, such as smoking, diet and lack of exercise have recently been seriously challenged by a growing body of evidence that disturbed early growth and development, childhood infection, poor nutrition, and social and psychosocial disadvantage across the life-course affect chronic disease risk, including chronic oral disease. This relatively new area of research is called life-course epidemiology. The life-course framework for investigating the aetiology and natural history of chronic disease proposes that advantages and disadvantages are accumulated throughout life generating differentials in health along the life-course, but most importantly later in life. Furthermore, its dynamic framework brings together the effects of intrinsic factors (individual resources) with extrinsic factors (environmental factors). The aim of this paper is to give an overview of this new epidemiological approach and to discuss how the life-course framework has been applied to chronic oral conditions.