The effect of repeated topical application of chlorhexidine (CLX)-containing varnish was evaluated in a three-year-clinical trial. The study was conducted on a group of children (aged 14–17) with high caries experience (DMFT §§§ 5). The CLX containing varnish CERVITEC (Vivadent) was applied in six-month-time intervals and patients were repeatedly examined clinically and bacteriologically (salivary mutans streptococci and lactobacilli). Re- sults showed that repeated application of CERVITEC varnish significantly decreased caries increment and improved gingival status and oral hygiene when compared with findings in the control group without CLX application. Screening evaluation of salivary levels of cariogennic bacteria did not reveal reproducible and sufficient predictive value. The topical antibacterial prophylaxis of caries by the CLX containing varnish is an effective and safe method suitable as an adjunct means to oral hygiene and fluoride prevention in individuals at higher risk of dental caries.

        Key words: caries risk children – antibacterial prophylaxis – chlorhexidin