Introduction
Many industrialised countries have experienced a decline in dental caries prevalence among children over the past decades. This trend of caries reduction may be ascribed to several factors of which the most important are improved oral hygiene, a more sensible approach to sugar consumption, effective use of fluorides, and school-based preventive programmes!. Against this, increasing levels of dental caries have been found in some developing countries, especially for those countries where preventive programmes have not been established. In the People's Republic of China, public oral health services are generally oriented towards treatment and mostly delivered from hospitals or health care centres. Since the late 1980s, the health authorities have given emphasis to preventive oral care and oral health education in order to improve the oral health behaviour of the public. With respect to the child population, behaviour modification may be a family responsibility, but oral health education could also be given by schoolteachers.