Ivoclar Vivadent SR Nexco Paste - Manual (Page 27)

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Anterior crowns
Premolar crowns
Molar crowns
2. Framework design for partial veneers (limited space conditions)
a different framework design is required for partial veneers (e.g. telescope and conus crowns). as the space in the
occlusal, palatal and lingual area in particular tends to be limited in many cases, this area of the restoration must be
designed in the metal in such a way that cracks or delamination cannot occur because of too thin layer thicknesses of
the lab composite. In this design, the transition between the metal framework and the lab composite should be clearly
defined and it should incorporate a right angle finish line. the transition areas between the metal framework and the
veneering composite must not be located in the contact point areas, nor on surfaces involved in masticatory functions.
a chamfer or wraparound technique is required in partial veneer preparations to provide adequate support for the
veneer. observe the palatal area in upper canines (canine guidance) and the occlusal area in posterior teeth. to obtain a
balance between esthetic and functional properties, it is advisable to reduce the mesial corner of the occlusal surface in
upper posterior teeth in particular to attain a harmonious esthetic appearance, especially when the buccal corridor is
exposed. 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. Please refer to the Instructions for Use of the corresponding alloy for further information.
Practical Procedure
– Fixed, Metal-Supported Restorations