Inlay, Onlay, Veneer Flashcards
(94 cards)
1
Q
what are indirect restorations
A
- restoration is fabricated outside of the mouth
- dental impression taken of prepared tooth then sent to lab or milled in office
2
Q
what can indirect restorations be used for
A
- inlays
-onlays - crowns
- bridges
- veneers
3
Q
what are the materials used for indirect restorations
A
- gold
- lithium disilicate- eMAX
4
Q
when do you place indirect restorations
A
- when margin exceeds 2/3 of the distance between central groove and cusp tip - MUST CAP WEAK CUSPS
- when margins and 1/2 distance between central groove and cusp tip - CONSIDER CAPPING WEAK CUSPS
5
Q
what is an inlay
A
indirect restoration that is placed within the cusp tips of a tooth
6
Q
does an inlay offer protection of the cusp from occlusal forces
A
no
7
Q
what are inlays used for
A
teeth with minimal caries and strong buccal and lingual cusps
- acceptable occlusion
8
Q
what is an onlay
A
indirect restoration that covers one or more cusps, extending through and beyond the cusp tip to the facial/lingual and proximal slopes of the covered cusps
9
Q
what principles does an onlay incorporate
A
the principles and advantages of both intracoronal and extracoronal indirect restorations
10
Q
in onlays what is occlusion in all functional positions supported by
A
restorative material
11
Q
what are the indications for onlays
A
- large carious lesions or existing defective restorations
- cracked teeth
- endo treated teeth
12
Q
when can endo teeth be used for onlays
A
- sufficient tooth structure to retain the onlay and allow for removal of undercuts
- when enough facial and lingual surfaces are relatively intact- otherwise crown
13
Q
when do you use an onlay instead of an inlay
A
- when the bucco-lingual width of the cavity prep is 1/2 way between central groove and cusp tip- consider onlay. OR 2/3 way between central groove and cusp tip- should onlay
- where the cusps are undermined after caries removal
- where the occlusion of the tooth must be altered
14
Q
what is a crown
A
indirect restoration that fully covers the occlusal surface of a tooth and uses the external walls for retention
15
Q
why do we do inlays and onlays
A
- preference over amalgam
- conserve tooth structure compared to crown
- esthetics
- RPD abutment
16
Q
why do inlays and onlays for RPD abutments
A
can better control rest seats and guide planes
17
Q
what are the disadvantages of indirect restoration
A
- expense
- requires 2 appointments if sent to a lab
- impression needed
18
Q
what are the advantages of indirect restorations
A
- strength of materials
- conservation tooth structure
- better control of restorations contours
19
Q
what are inlays made of
A
either gold or porcelain
20
Q
what are the principles to follow for inlays
A
- no undercuts; passive fit
- no sharp line angles
21
Q
what are the advantages of indirect gold
A
- strength: wont fracture
- wear resistance: will support contact and occlusion
- will maintain smooth surface
- better control of contact and contour
- potential for greater longevity
- conserves cementum and periodontal attachment versus restoring with a crown
22
Q
what are the contraindications for indirect gold
A
- facial or lingual caries or previous restorations
- crown is better to restore multiple surfaces
- need to compare margin length with that of a crown - patients with high caries rate
23
Q
how do you prepare a gold inlay
A
- divergence: short walls should have 2 degree divergence and long walls can have 5-7 degree divergence
- bevel: 1mm occlusal, axial pulpal line angle, 1mm gingival wall
- no sharp line angles
- dovetail
- no reverse S
- smooth proximal walls
- adequate proximal clearance of 0.5mm
24
Q
how deep are gold inlay preps
A
2mm
25
what is the purpose of dovetail in inlay prep
prevents distal displacement
26
what is the purpose of the bevel
protects enamel from fracturing
27
what is the internal form of an indirect onlay
rounded line angles
28
what are the prep requirements for a ceramic inlay- occlusal depth, isthmus
- occlusal depth: 1.5-2mm
- isthmus: at least 2mm wide
- no undercuts
- pulpal walls = smooth and flat
- facial, lingual and gingival margins should clear contacts by at least 0.5mm
- facial and lingual walls must diverse
- need passive insertion and greater than a 2-5 degree taper
29
why must the isthmus be so large in ceramic inlays
decreases chance of fracture of restorative material
30
why can you have diverging walls in ceramic inlays
restoration bonds to preparation walls
31
what are onlays made with
gold or porcelain
32
when would you do an onlay instead of an inlay
when prep gets too wide, onlay buccal and/or lingual cusps
33
what is clearance
the amount of space between teeth
34
what is reduction
the amount of tooth structure removed
35
do you need occlusal clearance or reduction with onlays
clearance
36
what are the depth cuts for gold onlays
- 1.5mm on functional cusp
- 1.0mm on nonfunctional cusp
37
do you bevel the non functional cusp or functional cusp in gold onlays
both
38
what are the principles for gold onlays
- cover both facial and lingual cusps of maxillary and mandibular teeth
- minimum of 1.5mm of gold to cover cusps supporting occlusion; 1.0mm for cusps not supporting occlusion
- reverse bevel of 1-2mm on cusps supporting occlusion; 1/2 mm on cusps not supporting occlusion
39
what are the indications for porcelain onlays
- esthetics
- large defects or previous restorations
39
what is the exception for cuspal coverage on maxillary tooth
- 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
40
what large defects or previous restorations would indicate a porcelain onlay
- wide labiolingual missing tooth structure
-teeth that require cuspal coverage
- contours of large restorations are more easily developed in the lab
- indirect materials are more durable than direct for replacing occlusion and contacts
41
what are the contraindications for porcelain onlays
- ceramics can fracture if they dont have sufficient bulk or are under excessive stress
- inability to maintain a dry field
- deep subgingival preparations- difficult to get impression, to finish and get good bonding
42
what are the advantages of porcelain onlays
- improved physical properties
- wear resistance
- reduced polymerization shrinkage
43
describe the wear resistance of porcelain
- porcelain wears opposing teeth the most and has the most resistance to wear
44
what is the order of what causes the most wear and wears the least to causes least wear and wears the most out of porcelain, lab processed composite, and direct resin composite
porcelain> lab processed composite > direct resin composite
45
where does polymerization shrinkage occur in porcleain onlays
- in the lab
- only material that can shink is the resin composite cement used in cementation
46
what are the disadvantages of porcelain onlays
- increased cost and time
- requires two patient appointments and a lab bill
- technique sensitivity- devotion to detail
- ceramics are brittle
- wear opposing dentition and restorations
- low potential for repair
- difficult try in and delivery
47
what is the clinical procedure for porcelain onlays
- remove old restorations
- excavate all caries
- undercuts are blocked out with a glass inomer liner/base or resin composite
- want rounded line angles to avoid stress concentration
- need adequate thickness for strength of porcelain
- well defined margins
- all margins should have a 90 degree butt joint cavosurface angle
- no external bevels
48
what are the reductions for porcelain onlays
- 2.0mm over functional cusps
- 1.5mm reduction over non functional cusp
-bulk of porcelain at margins- no bevel
- smooth internal line angles
- no ferrule margins
- ceramic retention base on surface area not opposing walls
- 0.5mm for proximal margins
49
what are the provisional considerations
- use eugenol free cement
- eugenol interferes with bonding
- if must use cement with eugenol important to pumice the tooth to remove eugenol
50
when are occlusal evaluations and adjustments done
after cementation because of the fragility of porcelain restorations
51
what is silanation
porcelain is acid etched with hydrofluoric acid and then silanated before cementation with a resin cement
52
what instruments are used for finishing and polishing ceramics
- medium to fine grit diamond instrument
- 30 fluted carbide burs
- rubber, abrasive, impregnaated porcelain polishing points
- diamond polishing paste
53
why do you not want any scratches or rough spots on the porcelain
it will wear enamel severely
54
what are the types of veneers
- indirect: feldspathic porcelain or lithium disilicate
- direct: composite
55
what are the indications for veneers
- instrinsic discoloration: tetracycline staining, fluorosis
- extrinsic staining: coffee, smoking, wine
- wear patterns
- poor restorations
- diastema closure
- rotated and misaligned teeth
56
what are the contraindications for veneers
- severely malpositioned teeth
- denuded dentin
- unavailable enamel
- poor oral hygiene
- beware of highly fluoridated teeth - issues with bonding
- no primary teeth
- adolescents
- pregnancy
- oral habits: bruxism
57
what are the indications for veneers
- good oral hygiene
- good perio health
- poor esthetics
- proper patient psychology
- caries free
- met dental needs
- informed consent and reasonable expectations
58
what are the advantages of porcelain veneers
- esthetics are excellent
- color- porcelain is best tooth subsititue
- bond strength - high to enamel
- periodontal health
- low wear and abrasion of porcelain restorations
59
what are the disadvantages of porcelain veneers
- time: multiple appointments
- cost compared to composite veneers
- some tooth prep, must have adequate room
- requires lab involvement and fee
60
what is the alternate treatment to porcelain veneers
- bleaching for discoloration
- microabrasion and macroabrasion
- direct composite veneers
- PFM/porcelain jacket crown
- ortho
61
what composite resin polishes the best
microfill
62
what are the advantages of direct composite veneers
- mask discolorations on a tooth
- least cost to patient
- usually one appointment
- can correct simple tooth rotation and diastema easily
63
what are the disadvantages of composite (direct) veneers
- susceptible to wear
- margin fracture and stain
- discoloration
64
what are the composite veneer procedures
- window preparation
- incisal lapping preparation
65
describe window preparation
- most often recommened
- remove only enough tooth structure to achieve optimal contours with final restoration
- incisal edge remains intact
- intra enamel preparation
66
what does intra enamel preparation in window preparation do
- provides space for materials to achieve maximum esthetics
- removes outer, fluoride rich layer of enamel
- roughens surface for improved bonding
- establishes definite finish line
67
describe incisal lapping prep
- prep includes incisal edge
- indicated when tooth needs to be lengthened or an incisal defect is present
68
what does minimal tooth prep result in
overcontoured veneers
69
what is microabrasion
- involves use of acidic and abrasive agents applied to enamel surface
- 37% phosphoric acid and pumic or 6% hydrochloric acid and silica
70
what is macroabrasion
- removal of enamel defect with bur
- 12 fluted carbide or diamond finishing bur, followed by 30 fluted carbide finishing bur
- polished with rubber point
71
what is the prep guide for porcelain veneers
made from wax to tell you how much reduction is needed to get ideal
72
where should prep be for optimal bond strength in veneers
in enamel!!!!
73
what materials are used for minimal prep veneers
- eMAX
- empress
- feldspathic porcelain
74
what are the reduction criteria for minimal prep veneers
- 0.3mm chamfer at margin or slightly subg
- thickness is 0.5-0.7mm on labial surface
- 1.5mm at incisal reduction
- 1-2mm reduction acceptable
- 90 degree butt joint is best
75
what are moderate prep veneers
- moderate alignment corrections, up to 3 step change in chroma or value, diastema correction less than 1 mm
76
what are the reduction criteria for moderate prep veneers
- 0.3mm chamfer at margin or slightly subgingival
- thickness is 0.8-1.0mm on labial surface
- 1.5mm at incisal reduction
- 1-2mm reeuction acceptable
- 90 degree butt joint
77
what mateirals are used for moderate prep veneers
- emax
- empress
- feldspathic layered porcelain
78
where does the gingival tooth prep end
at the gingival crest or 0.3-0.5mm subgingival
79
when severely discolored enamel how much reduction may be required at gingival margin
0.5mm
80
how much gingival reduction is necessary when the tooth is in linguoversion
none
81
contour the ____ amount necessary according to the material that you are using to restore the teeth
minimum
82
what is the summary of incisal margins
- minimum 1-2mm reduction
- no reduction of incisal if lengthening incisal edge
- rounded at all line angles
- butt shoulder on incisal
- no undercut between lingual and gingival
83
why is there no lingual margin
- seating issues
- lingual margin failure from inadequate porcelain thickness
- porcelain needs bulk when loaded
- incisal butt margin preferred
84
what should you provisionalize with
a temporary material such as dentsply
85
what do you use to fabricate provisionals
wax up
86
how do you insert veneer
- remove provisional and clean prep with nonfluoridated pumice
- clean interproximally lightly with finishing strip
- isolate with rubber dam and sometimes retraction cord
- etch teeth with 37% phosphoric acid in enamel for 30 seconds and dentin for 15 seconds
- place bonding agent
- place light cured composite cement in veneer and place veneer on tooth
- tack cure to clean cement from margin
- remove excess cement
- light cure full amount of time from buccal and lingual
- polish and check occlusion
87
why should you only use light cure for veneer insertion
- working time
- no color shift
88
how do you fix occlusion
diamond bur and water spray
89
why do you not want to overheat veneers when polishing
excess heat may cause degradation of cement bond
90
what are the common 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 hemostatic agent to stop bleeding around gingiva
- improper bonding technique
- failure to communicate effectively with patient
- starting a case that should have never been started
91
why dont you use hemostatic agent
it will stain margins- use aluminum chloride- hemodent instead
92
what can improper bonding technique lead to
microleakage and bacterial growth under restoration
- black staining
93
