The elementary school Vuk Karadzic marked the World Day of Oral Hygiene and Teeth Protection. Today the dentists presented to the children the proper way of brushing the teeth. The school children prepared the special program with the theme dedicated to oral hygiene. Nis City Council Member Bojan Krstic attended the event on the behalf of Nis City. The campaign will last all week in all primary schools in Nis. The organizers of the campaign are the Association of dentists under the auspices of the City of Nis and Red Cross Organization City Office.