Introduction. Clinical and epidemiological data indicate that thorough removal of dental plaque reduce the intensity of dental caries and periodontal diseases.

The aim. The aim of the study was to evaluate the condition of oral hygiene in 12-year-old children and the influence of selected factors on the oral hygiene.

Material and methods. 414 twelve-year-old primary school children and their parents from Lublin participated in the study. The examined population was divided into three groups. The first group consisted of 111 students from health promoting schools with a dentist’s office; the second one – 149 students from schools with a dentist’s office but not promoting health; the third one – 154 students from schools without a dentist’s office. The evaluation of the oral hygiene was carried out by means of the Simplified Oral Hygiene Index (OHI-S) by Green i Vermillion. In order to compare the condition of oral hygiene a division into three groups (good, satisfactory and poor) was made on the basis of the value of OHI-S. The parents filled in the socio-demographic questionnaires.

Results. The mean value of OHI-S in the studied population of Lublin 12-year-olds was 1.90 and fell within the satisfactory range. Beyond any doubt it is an unfavourable phenomenon. The best level of oral hygiene was observed in the children from health promoting schools with dental care. A significantly lower level of oral hygiene was observed in boys than in girls. The age of mother, the education of parents and material status of the family are the factors contributing to the level of oral hygiene of a child.

Conclusion. Activities which aim at appropriate hygiene in children should be complex, i.e. many people and institutions both from the medical field and from elsewhere should be involved. Undoubtedly, parents and school have a very important role to play.