Effectiveness of a Highly Concentrated Chlorhexidine Varnish in Orthodontic Patients

Objective: The aim of the present study was to evaluate the recolonization pattern of Mutans Streptococci (ms) on densely colonized teeth with fixed orthodontic appliances after treatment with a 40% chlorhexidine (CHX) varnish (EC 40®, Explore Nijmegen). Methods: Healthy subjects with fixed orthodontic appliances (n= 19)and high bacterial ms counts in saliva (≥10⁵ CFU/ml) were recruited. For baseline registration plaque around brackets was sampled and cultivated on Dentocult® strips (Orion Diagnostica, Finland). Following professional tooth cleaning, CHX varnish was applied on all teeth for 8 min. The degree of recolonization with ms was assessed 2 weeks after varnish application in plaque around the brackets. Results: After 2 weeks no ms suppression could be stated. The ms values were not statistically different to baseline values. Conclusions: The results indicate that application of a highly concentrated chlorhexidine varnish in patients with fixed orthodontic appliances does not result in reduced ms numbers.