Bacterial penetration of restored cavities

The aim of this study was to assess the quality of the marginal seals of 7 restoratives by means of a bacterial penetration test in vitro. Sixty intac t premolars and third molars that were scheduled for extraction were used i n the test. There were 2 experimental groups of teeth, as follows: (1)A cla ss V conventional cavity and a wedge erosion cavity were prepared on the bu ccal surface and the lingual surface, respectively, of each tooth. (2) A cl ass V conventional cavity and a wedge erosion cavity were prepared on the b uccal surface and the lingual surface. respectively, of each tooth with a c ompletely removed enamel layer. The cavities were then reconstructed with d ifferent restorative materials. The quality of the marginal seals was evalu ated by submerging the teeth in a bacterial suspension and incubating them in an anaerobic milieu at 37 degreesC for 20 hours. The teeth were subseque ntly processed for histologic data and bacterial staining. The best margina l sealing in both the wedge erosion and the class V cavities was provided b y the Herculite/Optibond system and the Valux Plus/Scotchbond Multipurpose system. Bacterial penetration was slightly greater with the Luxat compomer and the Dyrect compomer, as well as with Vitremer glass ionomer cement and Fuji LC glass ionomer cement. The bacterial penetration test showed that th e use of restorative material does not entirely eliminate microleakage.