Veneering over an existing crown CAN be done, the bond is fine and should work, but normally the better choice is to replace the entire crown. It is usually done as a cost saving measure, but often in the long run there is no real savings if the crown eventually needs replacing anyway.
Can You Place a Veneer over an Existing Porcelain Crown?
Doctor Answers 2
Veneering over an existing dental crown is usually not a good idea
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