Inlay, Onlay, and Veneers Flashcards
Restoration fabricated outside of the mouth:
indirect restoration
Describe the process of impressions for indirect restorations:
impression is take of the prepared tooth and sent to the lab or milled in-office
Inlays, onlays, crowns, bridges, and veneers are all examples of:
indirect restorations
What covers more surface area, an inlay or onlay?
onlay
What materials are used for indirect restorations?
- gold
- lithium discilicate (EMAX)
When should you place an indirect restoration?
- when margin exceeds 2/3 the distance between the central groove and cusp tip
- when margins end 1/2 distance between central groove ad cusp tip
When placing an indirect restoration for a tooth that the margin exceeds 2/3 of the distance between the central groove and cusp tip, you must:
cap weak cusps
When placing an indirect restoration for a tooth that the margins end 1/2 distance between central groove and cusp tip, consider:
capping weak cusps
Indirect restoration that is placed within the cusp tips of a tooth:
Inlay
This type of indirect restoration offers no protection of the cusp from occlusal forces:
inlay
Inlays are used for teeth with: (2)
- minimal caries and strong buccal and lingual cusps
- acceptable (normal) occlusion
Indirect restoration that covers one or more cusp tips, extending through and beyond the cusp tip to the facial/lingual and proximal slopes of the covered cusps:
onlay
Onlays incorporate the principles and advantages of both:
intracoronal and extracoronal indirect restorations
Describe the occlusion with an onlay:
occlusion in all functional positions I supported by restorative material rather than tooth structure
Indications for onlays include: (3)
- large carious lesions
- existing defective restorations
- endo treated teeth
- cracked teeth
Onlays can be used on endodontically treated teeth only when: (2)
they have sufficient tooth structure to retain the onlay and allow for removal of undercuts
and
when enough facial and lingual surfaces are relatively intact
If an onlay is not an option for an endo treated tooth, what should be used?
crown
When do we use an onlay instead of an inlay?
- when the BL width of the cavity preparation is 1/2 distance between central groove and cusp tip
- when the BL width of the cavity prep is 2/3 distance between central groove and cusp tip
- where the cusps are undermined after caries removal
- when the occlusion of the tooth must be altered
Should you do an inlay or onlay in the following scenario?
The BL width of the cavity prep is 1/2 the distance between central groove and cusp tip
CONSIDER onlay
Should you do an inlay or onlay in the following scenario?
The BL width of the cavity prep is 2/3 the distance between central groove and cusp tip
should ONLAY the cusp
An indirect restoration that fully covers the occlusal surface of the tooth and uses the external walls for retention:
crown
What does a crown use for retention?
external walls of the tooth
Why do we do inlays and onlays? (4)
- preference over amalgam
- conserve tooth structure (compared to crown)
- esthetics
- removable prosthodontics abutment
Why would we use an inlay or onlay for a removable prosthodontics abutment?
can better control rest seats and guide planes
Disadvantages of indirect restorations: (3)
- expense
- requires 2 appointments
- impression is needed
Advantages of indirect restorations: (3)
- strength
- conservation of tooth structure
- better control of restorations contours
What are two principles to follow with indirect restorations?
- no undercuts; passive fit
- no sharp line angles
Advantages of gold indirect restorations: (6)
- strength
- wear resistance
- will maintain smooth surface (no tarnish or corrosion)
- better control of contact and contour
- potential for greater longevity
- conserves cementum and periodontal attachment versus restoring with a crown
T/F: With a gold indirect restoration, we have better control of contact and contour especially for large proximal caries where an amalgam would not restore contact and contours:
true
Contraindications for a gold indirect restoration:
- facial or lingual caries or previous restorations (crown is better to restore multiple surfaces)
- need to compare the margin length with that of a crown in some instances
- patients with high caries rate
Why is it a contraindication to use a gold indirect restoration on facial or lingual caries or previous restorations?
crown is better option to restore multiple surfaces
For patients with a high caries rate is a gold indirect restoration a good option?
no
MO gold inlay-
Divergence
- short walls:
- long walls:
Bevel:
NO ____.
short walls: 2 degrees
long walls: 5-7 degrees
Bevel:
1. occlusal = 1.0mm
2. axial pulpal line angle
3. gingival wall = 1.0 mm
NO sharp lines angles
MO gold inlay occlusal internal form =
2.0 mm deep
Do you dovetail a gold inlay prep? Explain:
Yes- prevents distal displacement
Do you use a reverse S curve in a gold inlay preparation?
NO- prep is more straight and angled; gold has strength at edge (whereas amalgam doesn’t)
What is the adequate proximal clearance of a gold inlay preparation?
0.5 mm with smooth proximal walls
What is the function of a bevel?
protects enamel from fracturing
Ceramic inlay-
Occlusal depth=
Isthmus width=
Pulpal walls=
F, L, G margins should clear contacts by atleast:
occlusal depth: 1.5-2.0mm
Isthmus width: 2.0 mm
Pulpal walls= smooth & flat
F,L,G margins should clear contacts by atleast 0.5mm
For a ceramic inlay, facial and lingual walls MUST:
diverge
For a ceramic inlay, need ____ Insertion and garter than a _____degree taper
passive insertion; 2-5 degree
For a ceramic inlay, the restoration ___ to the preparation walls
BONDS
The base of the main cavity for a ceramic inlay should be:
flat
In a ceramic inlay, occlusal margins may not coincide with:
occlusal contacts
In a ceramic inlay, margins should be prepared to a ____; alternatively they should present a hallow ____ in an attempt to create an “invisible” margin
90 degree cavosurface line angle; ground chamfer
If a prep gets too wide, you must:
onlay either buccal and/or lingual cusps
An inlay acts as a ____ whereas an onlay ____
wedge; protects
For an onlay, we need ____; This is NOT the same as ___-
occlusal clearance; reduction
The amount of space between the teeth:
clearance
The amount of tooth structure removed:
reduction
Gold onlays:
Depth cuts
- lingual (functional cusp):
- facial:
lingual: 1.5mm
facial: 1.0mm
What cusps are beveled with a gold onlay?
both non-functional and functional cusps
In gold onlays, the retention from short axial walls =
2 degree divergence
The main principle for gold onlays, is to cover:
both facial and lingual cusps of maxillary and mandibular teeth
What is the minimum amount of gold to cover cusps of SUPPORTING occlusion in a gold onlay?
What is the minimum amount of gold to cover cusps of NONSUPPORTING occlusion in a gold onlay?
1.5mm
1.0 mm
Describe the bevel on cusps supporting occlusion in a gold onlay:
Describe the bevel on cusps NOT supporting occlusion in a gold onlay:
REVERSE bevel of 1-2mm
REVERSE bevel of 0.5 mm
What is an exception for cusps coverage with gold onlays? (typically both facial and lingual cusps are covered)
exception for esthetics on maxillary teeth
What is the exception for esthetics on maxillary teeth with gold onlays?
Do not cover the facial cusp of maxillary molar or premolar if supported by strong tooth structure
(Modified “esthetic” coverage of facial cusp if weak)
Indications for porcelain onlays: (2)
- esthetics
- large defects or previous restorations
Describe some large defects or previous restorations that would indicate the use of a porcelain onlay: (4)
- wide labiolingual missing tooth structure
- teeth that require cusps coverage
- contours of large restorations (easier to make these in lab versus a typical restoration)
- for durability when replacing occlusion and contacts
Contraindications for porcelain onlays include: (4)
- Locations where we can’t obtain sufficient bulk
- areas under excessive stress
- inability to maintain a dry field
- Deep SubG preps
What are some advantages of porcelain onlays? (3)
- Improved physical properties
- Wear resistance
- Reduced polymerization shrinkage
_____ wears the opposing teeth the most but has the most resistance to wear
porcelain
can polymerization shrinkage occur with porcelain onlays?
yes- but all shrinkage occurs in the lab, the only material that can shrink is the resin composite cement which is used during cementation
Disadvantages to porcelain onlays: (6)
- increase cost and time
- technique sensitive
- ceramics are brittle
- ceramics wear opposing dentition and restorations
- low potential for repair
- difficulty try in and delivery
The clinical procedure for a porcelain onlay includes: (3)
- remove old restorations
- excavate all caries
- block out undercuts with glass ionomer/base or resin composite
What type of line angles should be present in a porcelain onlay? What bur accomplishes this?
rounded internal line angles; round end bur (such as 245)
Why should all line and point angles (internal and external) be round in a porcelain onlay?
to avoid stress concentrators
Porcelain onlays-
Functional cusp reduction:
Non-functional cusp reduction:
Bulk of porcelain @ ___, NO ___
_____ internal line angles
No _____ margins
- functional cusp reduction: 2.0mm
- Non-functional cusp reduction: 1.5mm
- Bulk of porcelain @ margins- NO bevel
- Smooth internal line angles
- No ferrule margins
In a porcelain onlay, ceramic retention is based on:
surface area; NOT opposing walls
For a porcelain onlay, we need adequate thickness for:
strength of restorative materials
The margins in a porcelain onlay should be ____ and have a:
well defined and have a 90 degree butt-joint cavosurface angle
What is the purpose of the 90 degree butt-joint cavosurface angle in a porcelain onlay?
ensures marginal strength
What should NOT be present with a porcelain onlay?
NO external bevels
Thin ceramic margins are prone to:
fracture
Describe the proximal margins requirements for a porcelain onlay:
need adequate clearance (0.5mm) from adjacent teeth for die separation
Should exit angle break contact in a porcelain onlay?
YES
Provisional considerations:
Use ____ cement because:
eugenol-free; eugenol interferes with bonding
Provisional considerations:
If you must use cement containing eugenol, it is important to:
pumice tooth well to remove eugenol
Provisional considerations:
_____ & _____ are delayed until after cementation because of fragility of porcelain restorations
occlusal evaluations and adjustments
The ____ in a provisional are larger than the gold inlay and onlay margins
marginal gaps
What step in a provisional is often completed by the lab, but if not, you need to make sure you do it yourself:
Silanation
Describe what must occur with a provisional before cementation with a resin cement:
Porcelain is avid etched with hydrofluoric acid and the silanated
What instruments may be used for finishing and polishing ceramics?
- medium to fine grit diamond instrument
- 30-fluted carbide bur
- Rubber, abrasive impregnated porcelain polishing points
- diamond polishing paste
A thin covering used to hide the under layer:
veneers
Types of veneers include:
- indirect
- direct
Indirect veneers are most commonly made of:
feldspathic porcelain or lithium discilicate
Direct veneers are most commonly made of:
composite
Indications for veneers include: (6)
- intrinsic discoloration
- extrinsic discoloration
- wear patterns
- poor restorations
- diastema closure
- rotated and misaligned teeth
Examples of intrinsic dislcoloration include:
- tetracycline staining
- fluorosis
Examples of extrinsic discoloration include:
- coffee
- smoking
- wine
Contraindications for veneers include: (9)
- severely malpositioned teeth
- denuded dentin
- unavailable enamel
- poor oral hygiene
- beware of highly fluoridated teeth
- no primary teeth
- adolescents
- pregnancy
- oral habits (bruxism)
Porcelain veneer indications:
- good oral hygeine
- good periodontal health
- poor esthetics (something that will be improved)
- proper patient psychology
- caries free
- met dental needs
- INFORMED CONSENT/REASONABLE EXPECTATIONS
The main advantage of porcelain veneers is:
Excellent esthetics
Disadvantages of porcelain veneers: (4)
- time
- cost (compared to composite veneers)
- some tooth prep (must have adequate room)
- laboratory involvement and fee
Price of composite veneers:
$ 100-150
Alternate treatment to porcelain veneers:
- bleaching for discoloration
- micro and macroabrasian
- direct composite veneers (microfill composite resin polishes best)
- PFM/porcelain jacket crown
- Orthodontics
What type of direct composites veneers polishes best?
microfill composite resin
Advantages of composite veneers (direct): (4)
- masks discoloration of a tooth
- less cost to patient
- usually one appointment
- can correct simple tooth rotation and diastema easily
Disadvantages of composite (direct) veneers:
- susceptible to wear
- margin fracture and stain
- discoloration
What more technique sensitive? Direct (composite) veneers or indirect veneers?
Direct (composite) veneers
Direct composite veneers are often less _____ compared to lab fabricated veneers
esthetic
Why do we do an intra-enamel prep with a composite veneer?
- provides space to achieve maximum esthetics
- removes outer fluoride rich layer of enamel (resistant to etching)
- roughens surface for improved bonding
- establishes definite finish line
What is the most often recommended preparation for composite veneers?
window preparation where the incisal edge remains intact
Type of composite veneer preparation where as much tooth structure as possible is conserved and the insical edge remains intact:
window preparation - (recommended)
Type of composite veneer preparation where the preparation includes the incisal edge and is indicated when tooth needs to be lengthened or there is an incisal defect that needs to be corrected:
incisal lapping preparation
Some clinicians do too minimal tooth preparation with veneers that leads to:
over contoured (bulky) veneers
Involves use of acidic and abrasive agents applied to enamel surface
microabrasian
Describe what is used for microabraisian:
37% phosphoric acid and pumice or 6% hydrochloric acid and silica
Removal of enamel defect with bur:
macroabrasion
Describe what is used for macroabrasian:
12 fluted carbide or diamond finishing bur, followed by 30 fluted carbine finish bur and the polished with a rubber point
What is a very important early step in the porcelain veneer procedure?
diagnostic wax up
(to see what can be done for you and your patient)
Used in the porcelain veneer procedure; made form wax up, and tells you how much reduction is needed to get dial from wax up:
prep guide
____ prep is needed for porcelain veneers
minimal
For porcelain veneers, try to keep prep in ___ for ____
enamel for optimal bond strength
Reduction for porcelain veneers depends on:
material and changes desired
Put in order of greatest to least flexure strength for the following materials used in porcelain veneers:
Lithium discilicate
Feldspathic porcelain
Leucite glass ceramic
Lithium discilicate (500 MPa)
Leucite Glass Ceramic (160 MPa)
Feldspathic Porcelain (100MPa)
- 0.3mm chamfer at margin or slightly SubG
- thickness is 0.5-0.7 mm on labial surface
- 1.5mm incisal reduction
(1-2mm reduction is acceptable & 90 degree butt joint is best)
Minimal Prep Veneers
What materials can be used for minimal prep veneers?
- E. Max (pressed monolithic ceramic)
- Empress (pressed ceramic)
- Feldspathic porcelain (etched porcelain)
Used in situations of:
- moderate alignment corrections
- up to 3 step change in chrome or value
- diastema correction of less than 1mm
moderate prep veneers
- 0.3 mm chamfer at margin or slightly subG
- thickness is 0.8-1.0mm on labial surface
- 1.5mm of incisal reduction
(1-2 mm reduction is acceptable & 90 degree butt joint is best)
Moderate prep veneers
Materials used for moderate prep veneers:
- E. Max (pressed monolithic ceramic)
- Empress (pressed ceramic)
- Feldspathic porcelain (etched porcelain)
When would you exceed the gingival crest or 0.3-0.5 sub gingival prep for veneers?
when severely discolored enamel is present you may have to go more sub G
For veneers, when the tooth is lingual version:
little to no gingival reduction is necessary
For tooth preparation in veneers, contour the ____ amount necessary according to the material you are using to restore the teeth
minimum
For the incisal margins of veneers, a minimum of ____ reduction is needed for material bulk or ____ reduction of incisal if lengthening inscisal edge
1.0-2.0mm; no reduction
What type of shoulder should be seen on the incisal margin of veneer preps?
Butt shoulder
Why do we not incorporate a lingual margin for veneer preps?
- seating issues
- lingual margin failure from inadequate porcelain thickness
- porcelain needs bulk when loaded
- incisal butt margin preferred
What should you use as a matrix to fabricate provisionals of porcelain veneers?
Provisionals are made with temporary material such as:
wax up; Denstply integrity
Veneer insertion:
Remove provisional and clean prep with:
non fluoridated pumice
Veneer insertion:
Clean interproximal lightly with:
finishing strip
Veneer insertion:
Isolate with:
rubber dam and sometimes retraction cord
Veneer insertion:
Etch with:
37% phosphoric acid
(if in enamel for 30 seconds)
(if in dentin for 15 seconds)
Veneer insertion:
After etching with 37% phosphoric acid, you should place:
bonding agent
Veneer insertion:
Place ___ in veneer and place veneer on tooth
light cured composite cement
Veneer insertion:
Why would you ONLY use a light cured composite cement?
- working time
- no color shift
(dual cure cements often have color change because of tertiary amines)
Veneer insertion:
_____ in order to clean cement from margin
tack cure
When should you polish and check occlusion with a veneer? Why?
after veneers have been bonded; because fracture risk
What should you use to polish a veneer AFTER bonding?
diamond bur and water spray
Avoid overheating when polishing veneers because:
excess heat may cause degradation of cement bond
In order, what are the top 7 mistakes with veneers?
- failure to address gingival asymmetry
- failure to do a wax up for the case
- failure to work with an experienced esthetic ceramist
- using ferric sulfate (astringent) hemostatic agent to stop bleeding around the gingiva (stains margins)
- improper bonding technique
- failure to communicate effectively with patient
- starting a case that should denser have been started in the first place- learn to say byeeee Felicia
What should avoid using with veneers to stop bleeding around gingiva? What should you use instead?
avoid: ferric sulfate hemostatic agent (Astringedent)- this shiiii stains
use: aluminum chloride (hemodent) instead
