Crowns can correct more severe tooth discolouration than veneers because they can be made thicker without affecting how well the crown can stay on the tooth.
Veneers should be bonded to mostly (or only) enamel for the best chance of long term success (the veneer not falling off or staining at the edges). To ensure that enamel remains after tooth preparation, only about 0.5mm of tooth structure can be trimmed off.
If the tooth to be treated requires drastic changes in angulation (to reduce protrusion), then a much more aggressive preparation is required for 2 reasons:
- To correct the angulation.
- To provide enough material thickness for the prosthetic tooth.
This usually disqualifies veneers as the treatment of choice for the very fact that almost zero enamel will be present on the tooth surface once the preparation is completed.
Even if crowns are made, there will still be issues with proper emergence profile (the shape of the crown around the gumline), potential pulp death (and subsequent need for root canal treatment) and bite issues if the teeth are not moved to the proper axial positions before prosthetic treatment.
Crowns are not a do-all treatment when faced with multiple aesthetic issues. Careful consideration of your goals is mandatory to ensure selection of the appropriate treatment.
