Transient reduction of mutans streptococci on tooth surfaces using a chlorhexidine-containing glass ionomer cement varnish.

Chlorhexidine (CHX) has been incorporated in polymer-based varnishes to reduce mutans streptococci (ms) by the sustained release of CHX. Such varnishes often adhere well to teeth initially but are easily peeled off. To be effective, repeated application is necessary. Glass ionomer (GI) cements interacts with tooth minerals to form a stronger bond, and the inherent brittleness of the cement makes it difficult to remove in large fragments. The fluoride content may also reduce demineralisation. The aim of this study was to observe whether ms could be reduced interproximally and in saliva by a single application of a GI cement containing 3.3% CHX gluconate (CHX-GI). After professional tooth cleaning and a mouth rinse for 2 min with 0.2% CHX, the teeth of six subjects were coated with CHX-GI cement. An additional six subjects were treated with a GI cement that did not contain CHX, and seven subjects received professional tooth cleaning only. Ms samples were taken interproximally with the tooth pick method before and after treatment. Interproximal levels were classified according to the number of colony-forming units (c.f.u.) found: 0, 1-20, 21-100, and > 100. Saliva ms were sampled with the Strip Mutans method. After four weeks, the interproximal levels of ms had decreased only in the CHX-GI group (p < 0.05). In this group 9 of 14 highly colonised sites (> 100 c.f.u.) remained reduced throughout this period. In the GI and the untreated group a slight increase of ms interproximally was seen after one week. The interproximal ms scores in all groups approached baseline levels after 8 weeks. There were no significant differences in saliva ms levels between the groups during the test period. GI cement may be a possible vehicle for CHX in reducing ms interproximally.