Secondary caries is one of the most important factors leading to replacemen
t of dental restorations. This investigation assessed the capacity of fluor
ide-releasing restorative materials to resist caries in vitro when used in
roots. Class 5 cavities were prepared in the buccal and lingual surfaces of
30 extracted premolars. The six materials used were: glass-ionomer cement
(Fuji(R)), glass-ionomer cement with silver particles added (Ketac-silver(R
)), fluoride-containing composite resin (Tetric(R)), composite resin (Silux
plus(R)), fluoride-containing amalgam (Fluor-Alloy(R)) and high-copper ama
lgam (Dispersalloy(R)). After 5 weeks in an acid gel for caries-like lesion
formation, the teeth were sectioned longitudinally and examined with polar
ized light. The results showed that repair with glass-ionomer materials of
a carious lesion may be of great importance in the prevention of secondary
caries around the restorations in roots.