Crowns are an example of indirect restorations, which are recommended to restore and strengthen weakened tooth structure. All-ceramic crowns offer the potential for superior esthetics in comparison to porcelain-fused-to-metal (PFM) crowns, although the latter may also result in a very good esthetic outcome. All-ceramic crowns can be made from numerous materials, but lithium disilicate and zirconia are amongst the most popular ones, due to the combination of excellent esthetics and very desirable mechanical properties. Here we will present an anterior tooth preparation (#11) to receive a monolithic lithium disilicate crown. Show The materials needed are:
The preparation of an anterior tooth for a lithium disilicate crown should follow this sequence of steps
The final dimensions of the preparation vary according to the restorative material to be used, either lithium-disilicate or zirconia. For lithium disilicate, the overall reduction is 1.0 mm with an incisal reduction of 1.5 mm and a 1 mm deep shoulder finishing line. For zirconia crowns, incisal reduction stays the same (1.5 mm), and overall reduction is approximately 0.7-0.8 mm. A bilayered zirconia crown will require more reduction. Consult the preparation quickguide and flowchart in the restorative manual for the recommended amount of reduction for all crown preparations. Article Reviewed By Dr. Greg Anderson & Dr. Joel Rosenbloom What is one of the main problems with allObjectives: Fracture strength measured in vitro indicates that most all-ceramic crowns should be able to withstand mastication forces. Nevertheless, fractures are one of the major clinical problems with all-ceramic restorations.
Which finish line is used in allChamfer Finishing Line Is Better Than Shoulder Finishing Line for All-Ceramic Crowns | PracticeUpdate.
Why was gutta percha removed from Mr delucas tooth #14 after the root canal was complete?The removal of gutta-percha from root-filled teeth is required for re-treatment of failed endodontic treatment and to prepare a space for placement of a post. Complete removal of filling material and sealer is a requirement for success.
Which are reasons for using a provisional crown?Temporary crowns protect the natural tooth from further damage or decay while the permanent crown is being crafted. They also ensure that the prepared tooth and the adjacent teeth don't change positions before the permanent crown is fitted.
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