Effect of a tight seal on survival of bacteria in saliva‐contaminated cavities filled with composite resin

Buccal Class V‐cavities were prepared on homologous pairs of human premolars in vivo under aseptic, conditions. The cavities were then contaminated by rubbing them with a cotton pellet soaked in saliva. Chosen by lot, 1 tooth in each pair was thereafter washed either with water spray or with an antimicrobial cleanser (Tubulicid®). The cavity was filled with Adaptic®. The cured filling was removed to about, half of the depth and replaced by a zinc, sulphate cement. Finally, an orthodontic band was cemented over the filling. The teeth were extracted after 6–8 weeks. Both culturing and histological techniques were used to assess possible growth of bacteria. The results showed no growth of bacteria under the composite resin restorations, independent of whether the cavity was washed with water or with an antimicrobial cleanser before filling. Thus bacteria originating from saliva contamination do not seem to survive under tightly sealed composite resin restorations.