It was recently noted that there are
serious trials to develop dental materials used in the prosthodontics.
As a result of this development, some veneering ceramic systems
used in metal-ceramic crowns have been appeared. In view of the
major impo
rtance of marginal fit and its role in the success of
restoration it must be a study and evaluation of marginal fit for these
modern systems.
This research aimed to comparasion of marginal fit for metal ceramic
crowns using two types of veneering ceramic.
The idea of use ceramic margins for metal-ceramic crowns was founded to
overcome problem of grayness for gingival margins that caused by metal collar in metal-ceramic crowns ,
but at the same time there are a lot of cautions on decrease mechanical
resistance for these restorations.
This study aims to study fracture resistance of metal-ceramic crowns with ceramic margins in 1 or 2 mm.
long, and compare it with mechanical resistance of metal-ceramic crowns with metal collar.
