Op 2 - Veneer Prep and Design Flashcards
What are the 3 indications for veneers? (ON EXAM)
Shape modification
Color modification
Space closure (diastema/peg lateral, < 2 mm of space)
What are the contraindications for veneers? (ON EXAM)
Bruxism (limited occlusal clearance)
Not enough remaining tooth structure
How much thickness is needed to change the hue of a tooth by one shade?
0.2 mm
What veneer thickness is most commonly used?
0.3 - 0.5 mm
If minimal shade changes/tooth position are needed, the prep may not include the full width of the _________ _________ (ON EXAM)
incisal edge
If a tooth needs to be “moved” lingually or a large increase in shade is needed, the prep may require replacing the full width of the incisal edge, ending in a _______ ________ w/ the enamel on the lingual surface of the tooth (ON EXAM)
butt joint
When is there no need to prep the tooth subgingivally? (ON EXAM)
In minor or non-shade changes
What is meant by minor shade change? (ON EXAM)
1 or 2 shades lighter
When may subgingival margin placement be necessary to achieve desirable esthetic results? (ON EXAM)
Gingival exposure when smiling
When are subgingival margins unavoidable?
Decay or old fillings extending under the gingiva
Restrictions to enamel are a necessity for marginal tooth preps and bonded restorations, including ceramic veneers, as exposure of the dentin margins may __________ bond strengths and increase the change of ___________ (ON EXAM)
reduce; micro-leakage
When is micro-leakage minimal or none at the tooth/luting composite surface and negligible in the porcelain/luting composite interface? (ON EXAM)
When prep margins are completely in enamel
Avoid final margins in areas that risk _________ exposure (ON EXAM)
dentin
Patches of dentin exposure are not a problem during the prep, as long as finish lines are kept on __________ (ON EXAM)
enamel
In situations such as extensive carious lesions in gingival areas, placement of the subgingival margin can go as deep as to be placed on the dentin or cementum. What will become an issue? (ON EXAM)
Obtaining successful bond
(use common sense to determine need for full coverage)
When may specific prep of the interproximal area be required to allow the tech greater freedom in alteration of form or position? (5) (ON EXAM)
Closing diastema
Changing shape/position
Caries
Defects
Existing fillings
