Hot Topics Op 4 Final Flashcards
1
Q
Where is the location of the contact between the from the facial view central incisors?
A
-junction of incisal and middle third
2
Q
From the incisal edge view, where is the contact between the central incisors?
A
essentially in line with the incisal edge
3
Q
The embrasures generally follow what type of contour?
A
biological contour
line angles
4
Q
Width of contact inciso-gingivally
A
1-1.5mm
5
Q
Main etiology of Class IV
A
Fracture (sports)
Rampant caries
Fatigue
Congenital- osteogenesis/dentinogenesis imperfecta
6
Q
Why is composite the ideal restorative material for class IV restorations?
A
- better sealing on enamel margins
- better shade matching
- smooth and polished restorative material = great esthetics
7
Q
Type of burs to use for Class IV restorations
A
flame/small diamond
8
Q
Bevel for cavosurface margin
A
45 degrees
width of bevel 0.5-2mm depending on missing tooth structure
9
Q
Additional retentive features for class IV restorations
A
Bevels and chamfers
10
Q
Occlusal considerations for class IV restorations
A
try to keep end margins out of direct contact areas
keep protrusive and incisal forces to a minimum
look at existing state of teeth- wear facets and functional habits
11
Q
Best way to hide margins
A
Vertical and horizontal finish lines rather than oblique
12
Q
Etching the tooth for class IV restorations process
A
- etch for 20 sec
- rinse for 10 sec
- bond and light cure for 20 sec from lingual and facial surface
13
Q
Inherently thin
Cannot be bonded like conventional temporaries
Trimming
Lack of retention form
A
Common challenges of provisionalization for veneers
14
Q
Veneer provisional technique
A
Prep Impression Diagnostic wax up ESF Spot etch- 35-37% phosphoric acid Rinse and dry NO ADHESIVE Load ESF with Bis-acryl resin and press on prepped teeth
15
Q
Strength of multi-unit provisional veneers
A
- collective strength and bond to etched points on teeth
- NOT USED FOR FUNCTION
16
Q
Veneer cementation procedure for definitive restorations
A
- remove provisional material remaining on the etched portions of the teeth
- Clean teeth- pumice slurry
- rinse and dry
- isolation- lip retraction or cotton rolls
- retraction cord packing
- evaluation
- application of silane
- etch- 20 sec, rinse and dry, bond, cure, cement, eval margins, light cure
17
Q
This process helps to prevent contamination during try in/cementation
A
retraction cord
18
Q
This acts as a coupling agent to form a chemical bond to increase bond strength and is applied to intaglio of veneer
A
silane coupling agent
19
Q
What is the primary source of retention with a porcelain veneer?
A
-mechanical
20
Q
What should you use to remove marginal excess from veneer cementation process?
A
- # 12 blade
- fine flame diamond- carefully recontour and dress gingival margins if excess cement
21
Q
What instrumentation is used to finish the lingual margins of the veneer?
A
-oval-shaped fine diamond
22
Q
How to remove striations from diamonds?
A
-rounded end/bullet-shaped, 30-fluted carbide finishing bur
23
Q
Polishing burs for veneers
A
- abrasive rubber
- porcelain polishing cups and points
24
Q
What kind of cement used for veneers?
A
- resin cement (light cure due to thinness of restoration)
- light cured for thin
- dual cure for thick
25
Recommendations for light cured resin cement
- longer working time
| - thinner ceramics
26
Recommendations for dual cured resin cement
-thicker ceramic restorations (crowns, inlays, onlays with limited light penetration)
27
Which veneers can be repaired?
porcelain
| composite veneers
28
Process of repairing veneers
- roughen damaged margins with fine diamond
- bevel or chamfer the veneer edges
- chairside microetching (sandblasting) can also be effective
- etch with HF acid if repairing ceramics and rinse
- adhesive for composites
- silane for porcelain margins
29
Main conservative esthetic treatment options for discolored teeth
- bleaching
- micro/macroabrasion
- tooth recontouring (reshaping)
- partial veneers
- full veneers (composite/porcelain)
30
best bleaching option
-conventional 10% carbamide peroxide system with custom trays
31
This is a conservative procedure used to reduce/eliminate superficial discoloration. Requires chemo-mechanical/mechanical adjustment. Abrades stains and defect within 0.2mm of the surface.
-micro/macro abrasion
32
This is the composition of the chemo-mechanical slurry
-6.6% HCl slurry with silicon carbide microparticles
33
This conservative procedure helps to improve appearance and function. Some esthetic problems can be corrected conservatively without the need for restoration. Rounding of the sharp angles can be considered a prophylactic measure to reduce stress, prevents chipping and fracture of the incisal edges.
Enamel recontouring
34
What conservative procedure would you suggest?
- Localized intrinsice discolorations or defects
- One appointment
- White spot lesions
- surface defects
- Direct partial veneer with composite
| - or micro/macro abrasion
35
Advantages of direct composite veneers
- one appointment
- little or even no prep
- dentist controls the process
- less expensive
- useful in young patients
36
Disadvantages of direct composite veneers
- more maintenance
- difficult to manage
- time consuming/fatiguing
- patient management
- changes over time
- technique sensitive
37
These are indications for which kind of conservative esthetic procedure?
- teeth with malformed surfaces- severe hypoplasia
- Discolored teeth
- teeth with severe abrasion or erosion
- teeth with significant faulty restorations
- diastemas/tooth-arch size discrepancies
Direct full/indirect veneers
| Potential ortho and restorative
38
These are advantages of what conservative esthetic technique?
- Lab controlled contours
- stable appearance over time
- biomemetic
- multiple tooth restorations
- potential to last a long time
-Indirect porcelain laminate veneers
39
These are disadvantages of what conservative esthetic technique?
- 2 appts
- 3-5x more expensive
- technique sensitive bonding
Indirect porcelain laminate veneers
40
What kind of restoration is this process for?
1. Intra-enamel prep
2. Supra-gingival margins if possible or sub-gingival if in esthetic zone
3. Window, butt-joint, or lap prep incisally
Indirect porcelain laminate veneers
41
What kind of incisal edge prep?
| For teeth that require no shape modifications/no incisal wear present
Window prep
42
What kind of incisal edge prep?
| For most teeth that need some incisal modification due to wear
Butt-joint
43
What kind of incisal edge prep?
| For teetht hat have extensive incisal wear and need considerable lengthening. Adds F-L retention form.
Incisal lapping preparation
44
Characteristics of what type of veneer prep?
Chamfer margin: 0.4-0.6mm wide
Location of margin: 0.5mm from free gingival margin
Extends lingual to the M & D line angles at 1mm or more
Visually in contact, and proximally extends lingual to mid point of contact
Don’t break contact!
Facial reduction: 0.5mm uniform
Incisal reduction: 1.0mm
Round off incisal- facial line angles – no sharp areas
Incisal lingual line angle – 90 degree cavosurface junction
Incisal butt joint preparation
45
This is a fixed intracoronal restoration made outside of a tooth to correspond to the form of the prepared cavity which is then luted into the tooth
-inlay
46
Indications for what kind of restoration?
- Large failing restorations
- Teeth at risk of fracture
- Endodontically treated teeth
- Diastema closure
- Occlusal plane correction
- RPD abutment
cast metal restoration (inlay/onlay)
47
Contraindications for what kind of restoration?
- High caries rate
- Young patients
- Esthetics
- Small restorations
-Cast metal restorations (inlay/onlay)
48
Advantages of what kind of restoration?
- Superior strength
- control of contour and contacts
- biocompatibility
- low wear
- no discoloration
-cast metal inlay/onlay
49
Disadvantages of what kind of restoration?
- Chairside time
- appts
- gold color/cost
- provisionals
- technique sensitive
- splitting forces
-cast metal inlay/onlay
50
Indications for what kind of restoration?
- Esthetic restorations
- Proximal margins not in enamel
- Large defects or previous restorations
- multiple teeth/multiple surfaces
-indirect tooth colored inlay/onlay
51
Contraindications for what kind of restorations?
- Heavy occlusal forces
- Isolation issues
- Deep sub-G preps
-indirect tooth colored inlay/onlay
52
Advantages of what kind of restoration?
- Improved physical properties
- Variety of materials and techniques
- reduces polymerization shrinkage
- reduced microleakage over direct composite
- more precise control of contours and contacts
- support of remaining tooth structure
- wear resistant
- biocompatible
- increased auxiliary support
-indirect tooth colored inlay/onlay
53
Disadvantages of what kind of restoration?
- chairside time/cost
- difficult try in/delivery
- brittleness of ceramics
- wear of opposing dentition/restorations
- low potential for repair (ceramic)
- short clinical track record
-indirect tooth colored inlay/onlay
54
What kind of prep?
- all walls tapered 2-5* diverging to occlusal
- No undercuts
- Primary and secondary flares
- gingival bevel
- occlusal bevel
Metal inlay/onlay replacing large amalgam
55
What kind of prep?
- 2.0mm in central fossa
- 2.0mm in F-L dimension isthmus
- 1.25-1.5mm axial depth
- 6-10* divergent taper
- Rounded internal line angles
- Smooth transitions/rolling margins
- 90* cavosurface exit angle
- 1mm clearance
- No bevels/avoid undercuts
-Esthetic inlay prep
56
This is tooth failure/fracture due to a single event of biting on something hard. Rare
-Single cycle overload
57
This is tooth failure/fracture due to cyclic loading well below fracture forces. Slow crack propagation over time
-Fatigue
58
How often do endo teeth fracture?
50-60% fracture in 7 years
59
What material is E. Max?
Lithium disilicate
60
What material is Empress, Paradigm C?
Leucite-reinforced glass ceramics
61
What kind of material is in the Lava Ultimate?
Composite blocks
62
What kind of restoration?
- Restore 1+ cusps and or adjoining occlusal surfaces
- Can restore entire occlusal surface
- Made outside of the mouth and then bonded to the tooth
-Onlay
63
When should you cap a cusp?
-when preparation is greater than 1/2-2/3 the intercuspal distance
64
- Fermit N - Ivoclar/Vivadent
- light curing single component composite resin
- stays soft, doesnt lock in
- easy to remove with spoon or sickle explorer
- Trim/Jet- needs cementation, more difficult to use
- Bis-Acryls composite resin with non-eugenol
- Dura seal- more flexible polymer (like Jet/Trim)
Good temporizing materials for inlays/onlays
65
What kind of prep?
- including inlay prep requirements
- 2mm reduction of functional cusp
- 1.5mm reduction of non-functional cusp
- 1-1.5mm collar preparation
- path of withdrawal for whole restoration
- No bevels/undercuts
-Esthetic onlay preparation
66
How does a digital impression system work?
- 3D picture of preparation
- surfaces are illuminated under a specific light (laser or projected pattern)
- light interaction with surfaces = plot of distances from camera
- computer processes distances plotted --> 3D digital model of area scanned
67
What are the different kinds of acquisition methods?
- 3D in motion video
- 2D pictures
- with or without powder
68
Why do we use powder?
- camera requires a uniformly reflective surface to capture optical images, this is established by the powder
- tooth structure tends to reflect the incident light and glare causing smearing artifacts
- enamel is translucent
69
What is in the powder spray?
- finer particle titanium dioxide
- blue color for visibility
- spearmint flavor
70
Process for packing cord
- soak in hemostatic solution
- squeeze dry in gauze prior to packing
- do not dab hemostatic solution around tissue
- leave cord in place through entire procedure, even bonding
71
CAD/CAM fabrication steps
- prep tooth
- pack cord
- bite registration- trim to tooth
- spray with powder if needed
- optical impression- 3 pictures- path of insertion, images of adjacent teeth present (8mm of overlap and same angulation)
- spray bite registration
- select antagonist- 3 images with bite registration
- hit next and save restoration
- mark margins
- design restoration
- adjust proximal, occlusal contacts and contours
- mill restoration
72
Diastema closure process
- evaluate space to make sure you don't need ortho
- measure teeth and space
- lightly prep and etch each tooth separately
- restore teeth 1 at a time
- shape interproximals with soflex finishing discs and strips
- make sure you have recreated embrasures and then treat like a class III or IV (margins, flash etc.)
- polish with green wheel 5000 rpm
- polish with gray wheel 4000 rpm
