Class IV Composites, Veneers Flashcards
What is a class IV prep due to?
“chipped tooth”
Fractured incisal edge
What is a class III prep due to?
Interproximal caries on an anterior tooth
Whats the difference between class IV and class III prep?
Class IV has a missing incisal angle
What class prep has a more extensive bevel and why?
Class IV has more extensive bevel than class III to increase retention and esthetics
Where is there a bevel on a class IV prep?
At minimum same amount of enamel that is missing due to fracture
What does a bevel do for enamel?
Improves the adhesive bond to enamel by 18%
When are lingual enamel margins NOT beveled?
When there is a heavy centric contact (areas of teeth that contact opposing arch) on the margin
What should you do on the lingual to compensate for no bevel?
Use a dovetail for retention without beveling
What is a veneer prep?
A thin covering (often to hide the under layer)
What are the two types of veneers preps?
- Incisal lapping
- Window prep
What does an incisal lapping prep do to the incisal edge?
Prep includes incisal edge (removes the incisal edge)
When is an incisal lapping prep indicated?
When tooth needs to be lengthened or incisal defect is present
What is the more common veneer prep?
Window prep
What does a window prep do to the incisal edge?
Remains intact
How is a window veneer prep done?
Remove only enough tooth structure to achieve optimal
contours with final restoration
Is a window prep an intra or extra enamel prep?
Intra enamel prep
What does it mean to be an intra enamel prep?
Removes fluoride rich layer of enamel (that is resistant to etching), roughens surface to aid in bonding, establishes definite finish line
What are common mistakes associated with veneers?
- Failure to do wax-up prior to prepping
- Failure to address gingival asymmetry
- Failure to communicate effectively with patient
(Everyone must have same expectation) - Don’t start a case that should have never been started (learn to say no)
What are the two ways to create veneers?
- Indirect
- DIrect
Where are indirect veneers made?
Made outside the mouth
What are indirect veneers made of?
Porcelain (more common)
Lithium disilicate
What are the advantages of indirect veneers?
o Excellent aesthetics
o Color match
o High bond strength
o Conducive with periodontal health
o Low wear/abrasion on porcelain restoration
What are the disadvantages of indirect veneers?
o Multiple appointments
o Expensive
o Must have adequate room for preparation
o Requires laboratory involvement and fee
o Difficult to keep provisional seated
Where are direct veneers made?
In the mouth
What are direct veneers made of?
Composite
What are advantages of direct veneers?
o Mask discoloration
o Cheaper than indirect
o One appointment
o Can easily correct rotated tooth or diastema
What are disadvantages of direct veneers?
o Susceptible to wear
o Margin fracture/stain
o Discoloration
o Contours
What materials give a better esthetic result?
Porcelain has better esthetics and color match compared to composite veneers
What are some alternative treatments to help patients with esthetic concerns?
- Bleaching for discoloration
- Microabrasion and macroabrasion (I assume this is polishing) for discoloration
- Orthodontics (rotation or diastema)
What are veneer indications?
- Intrinsic stain: Tetracycline, fluorosis
- Extrinsic stain: coffee/wine/smoking
- Wear patterns
- Poor restorations
- Diastemas
- rotated/misaligned teeth
What are veneer contraindications?
- Severely mispositioned teeth
- Denuded dentin
- Poor oral hygiene
- Highly fluoridated teeth (trouble bonding)
- Primary dentition/ adolescents
- Pregnancy
- bruxism
What material should be used to restore on the facial? lingual? both?
Facial: microfill
- smooth and stains less than hybrid
Lingual: hybrid
Both: nanohybrid
- strength and esthetics
