WHO recently published a global review of oral health (1) which emphasized that despite great improvements in the oral health of populations in several countries, global problems still persist. This is particularly so among underprivileged groups in both developing and developed countries. Oral diseases such as dental caries, periodontal disease, tooth loss, oral mucosal lesions and oropharyngeal cancers, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS)-related oral disease and orodental trauma are major public health problems worldwide. Poor oral health may have a profound effect on general health, and several oral diseases are related to chronic diseases (e.g. diabetes). The experience of pain, problems with eating, chewing, smiling and communication due to missing, discoloured or damaged teeth have a major impact on people's daily lives and well-being. Furthermore, oral diseases restrict activities at school, at work and at home causing millions of school and work hours to be lost each year throughout the world.
The objectives of the present paper are to outline the oral disease burden globally and to describe the influence of major sociobehavioural risk factors related to oral health. Sources of information are the WHO Global Oral Health Data Bank (2), the WHO Oral Health Country/Area Profile Programme (3) and scientific reports from population studies on oral health carried out in various countries. For both developing and developed countries, the oral health surveys recorded and used were based on nationally representative samples, obtained using either random sampling or pathfinder methodology (convenience sampling) (4). WHO standardized criteria are used for clinical registration of oral disease conditions and calibration trials are conducted for the control of quality of data and assessment of variability in results obtained by different examiners (4). The data stored in the databanks are updated regularly and the WHO Global Oral Health Data Bank is currently being linked with new information systems for surveillance of chronic disease and risk factors (5).
The burden of dental disease
Dental caries and periodontal disease have historically been considered the most important global oral health burdens. Dental caries is still a major health problem in most industrialized countries as it affects 60-90% of school-aged children and the vast majority of adults. In 2004, WHO updated the epidemiological information available in the databanks (2, 3). At present, the distribution and severity of dental caries vary in different parts of the world and within the same region or country. Fig. 1 illustrates the levels (severity) of dental caries as measured in 12-year-olds by the Decayed, Missing and Filled Teeth index (DMFT). Dental caries experience in children is relatively high in the Americas (DMFT = 3.0) and in the European Region (DMFT = 2.6) whereas the index is lower in most African countries (DMFT = 1.7) (1-3). Fig. 2 illustrates the time trends in dental caries experience of 12-year-old children in developing and developed countries. In most developing countries, the levels of dental caries were low until recent years but prevalence rates of dental caries and dental caries experience are now tending to increase. This is largely due to the increasing consumption of sugars and inadequate exposure to fluorides. In contrast, a decline in caries has been observed in most industrialized countries over the past 20 years or so. This pattern was the result of a number of public health measures, including effective use of fluorides, together with changing living conditions, lifestyles and improved self-care practices. However, it must be emphasized that dental caries as a disease of children has not been eradicated, but only controlled to a certain degree.
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Worldwide, the prevalence of dental caries among adults is high as the disease affects nearly 100% of the population in the majority of countries. …