Ivoclar Vivadent SR Nexco Paste - Manual (Page 26)

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the following points must be observed for the design of frameworks veneered with lab composite:
1. Framework design for full-coverage veneers (ideal space conditions)
With full-coverage veneers, the framework has to reflect the shape of the tooth in a reduced form. design the framework
in such a way that it supports the cusps resulting in a virtually even layer thickness of the lab composite. In this way, the
masticatory forces occurring during functional chewing are exerted on the framework rather than on the veneering
composite. In case of unfavourable preparations, the missing tooth structure has to be compensated by the design of the
framework and not the lab composite. furthermore, an even layer thickness facilitates the creation of a harmonious
shade effect while full-coverage veneering provides a maximum level of esthetic beauty and function. all areas of the
framework should be smooth and rounded to prevent delamination and cracking. angles and edges should be rounded
out already in the wax-up and not in the metal in order to avoid undermining the minimum framework thickness. the
thickness of the metal framework must not be less than 0.3 mm for single crowns and 0.5 mm for bridge abutments
after finishing.
fixed, metal-supported restorations
Anterior crowns
Premolar crowns
Molar crowns