L3 Anterior veneers Flashcards
What is an anterior laminate veneer?
- A thin section of porcelain, composite or gold that hides a disease, damaged or discoloured tooth to provide the illusion of a healthy/undamaged/better coloured tooth
Name indications for veneers.
Intrinsic discolouration:
- Trauma (pulpal haemorrhagic products)
- Hereditary conditions (amelogenesis/dentinogenesis imperfecta)
- Metabolic disease (alkaptonuria)
- Systemic and developmental factors (MIH, tetraycline staining, fluorosis)
Single/multiple tooth issues:
- Tooth malalignment
- Peg lateral
- Spacing
- Microdontia
- Localised trauma, chipped edges
- Discoloured facial restorations
What treatments may be a suitable alternative to veneers?
- Internal/external bleaching
- Direct facial composite placement
- Micro abrasion (e.g. ICON- bleaching and resin infiltrate)
- Orthodontics
- Implant and crown/bridge placement
- Removable partial denture
- Direct bonding composite replacement
What are the contraindications for veneers?
- Poor OH
- High caries risk
- Inability to achieve isolation
- Insufficient enamel to bond
- Parafunctional habits
- Unfavourable occlusion
- Thin gingival biotype (prone to recession)
- Single teeth (pt expectation vs delivery)
What 4 veneer types are there? List from least to most destructive.
- Window
- Feather
- Bevel/butt
- Overlap
Bevel and overlap are the most common type.
What are the advantages and disadvantages of a window preparation veneer?
- Minimal preparation
- Conserves the incisal edge
- Incisal edge enamel weakened
- Margins vulnerable to tooth wear
- Marginal join in the aesthetic zone (visible)
- Incisal luting agent may be difficult to hide
- Challenging to seat
What are the advantages and disadvantages of a feather preparation veneer?
- Incisal edge is maintained
- Interface between veneer and tooth hidden on/just behind incisal edge
- Substantial amount of enamel preserved
- Veneer is liable to be fragile at the incisal edge, incisal edge may fracture
- Subject to peel/sheer forces during protrusion
- Challenging to seat perfectly
What are the advantages and disadvantages of a bevel/butt edge preparation veneer?
- Greater control of incisal aesthetics
- Bigger bulk of porcelain at incisal edge gives greater strength
- Margin not subject to direct shear forces
- Easier to seat
Most common preparation choice.
- More extensive tooth preparation
- Cannot have more than 2mm of unsupported poreclain
What are the advantages and disadvantages of an incisal overlap veneer?
Also called modified butt/taco style
- Positive seating
- Tend to be more successful
- Preparation is more difficult and there is more tooth destruction
- When trying to fit the veneer, the path of insertion requires care and there is a risk of fracture
- Technically more difficult to produce
What are the benefits of bevel/butt and incisal overlap veneer types?
Where should the margin be for a ceramic veneer preparation?
Margins should be in enamel, not dentine.
How deep should the preparation be for a ceramic veneer?
- 0.3mm cervical (where enamel is thinnest)
- 0.5mm
- 0.5-0.7mm incisally
Where should the proximal finishing line be for a ceramic veneer?
Between the labial and palatal surfaces, hides the margin.
Do not extend beyond the contact points! Keep contact points intact.
How much incisal edge reduction is required for a ceramic veneer?
0.7-1mm if reduction is necessary.
Describe the steps for an anterior veneer preparation (bevel).
- Chamfer bur to reduce incisal edge by 0.7-1mm
- 2 plane labial reduction using chamfer bur
- Margin should be 0.5mm from cervical margin
- Bevel incisal-buccal interface
- Create proximal margins using chamfer bur, keep contact point intact
- Reduce any high spots
- Refine proximal margins with fine needle bur
- Make final refinement with a red band (fine grit) flame composite finishing bur
What is the final veneer shade dependent on?
- Ceramic shade
- Luting cement
- Underlying tooth
