Minimal intervention principles designed to limit the loss of natural tooth
structure should be applied to all cavities especially extensive ones, as well
as replacement of failed existing restorations. This study evaluates marginal
leakage of two
different techniques for the treatment of extensive occlusal
lesions with posterior composite resin- Amalgam and Glass ionomer-
Amalgam combined techniques, using two adhesive systems Syntac and
Exite. Thirty two extracted maxillary first premolars were used. Standard
extensive occlusal cavities with undermined cusps were prepared.