Final winter Flashcards
Benefits of crown lengthening
Increases ferrule size for resistance and retention
Five advantages of a partial veneer crown over a complete veneer crown
Less hydraulic pressure when seating Leaves tooth structure in case future pulp testing is needed Conserves tooth structure Easier to access margins Less margin near the gingiva
Benefit of a bone graft
Increases support for future restorations
Benefits of a soft tissue graft
Increases esthetics
Two requirements of solder
Lower melting temp than parent metal
Good wettability
What does soldering flux do?
Reduces contaminants from oxidation
The most esthetic Pontic in the maxilla
Ovate
Four requirements of a Pontic
Restore function of the tooth it replaces
Cleans ability
Esthetics and comfort
Must not injure tissue
What is a nonrigid Pontic connector used for?
When abutment teeth have different POI
Which Pontic design may require tissue modification to look good?
Ovate
Two parts of a nonrigid connector
Matrix and patrix
Two factors necessary to the success of a pontic
Biocompatibility and mechanical strength
What is the role of a post when used to restore a root canal treated tooth?
To support the core, which supports the crown
3 disadvantages of cementing a post into a RCT tooth that doesn’t need a core or crown
Removal of tooth structure
Complicates future RCT
Increases chances of root breakage
What kind of post do you need for a tooth with an ovoid or irregular root canal?
Custom
What is meant by an active post?
It is threaded like a screw
2 advantages of using a longer post vs a shorter one
Longer = more retention
Less likely that the root will crack
Two things the ferrule does for your restored tooth
Increases resistance
Increases fracture resistance
Two potential problems associated with using a parapost twist drill to remove gutty percha.
May dig into dentin and undermine it
May perforate the root
3 advantages of using the indirect method to make provisionals
Less exposure to heat
Less exposure to potential antigens
Easier to get good margins
What should be overcontoured in a provisional multi unit FPD?
The connectors
Which reinforcement for provisional FPD had the highest stiffness?
V shaped wire
Which tooth in the hazleton experiment lost cement seal first?
The premolar
Which material withstood the highest number of load cycles in the hazleton study?
Luxatemp hybrid composite
Four types of pins
Cast, cemented, friction grip, threaded
How deep to set pins?
2-3 mm
How far above the surface should the pins go?
2mm
What tool carries impression material into the canal for a custom post?
Lentulo spiral
3 important properties for a post to have
Stiffness
Strength
Corrosion resistance
Which post is not recommended for patients with bruxism?
Zirconia- too stiff, can crack the root
Disadvantages of zirconia post system(3)
Hard to remove
Hard to etch
Very stiff
When to use composite core material
Under CCC
When to use cast alloy for a core
When little tooth structure remains, or the tooth will be under heavy occlusal loads
When to use a ceramic core
When esthetics is an issue
What kind of core should not be used with zirconia posts?
Composite- poor bonding
What two core materials can be heat pressed onto a zirconia post?
Zirconia and ceramic
What is a zirconia post’s one weakness?
Never grind grooves into it
Why would you want to use a parapost/para core system?
For esthetic purposes
Indications for a partial veneer crown (2)
The tooth has an intact buccal surface and needs a cast restoration
As a retainer for a short bridge
Contraindications for a partial veneer crown (3)
Maximum retention required
No metal display desired
Restoration already on buccal surface
Occlusal clearance needed on a partial veneer crown
1.5mm
Location of the functional cusp bevel on a mandibular partial veneer crown
1.5mm south of the centric contact
Shoulder width on a partial veneer crown
.7mm
Width of the facial shoulder in a mandibular partial veneer crown
.7mm
What disaster do the grooves on a partial veneer crown prevent ?
The crown slipping off lingually
Exit angle for the proximal flare on a partial veneer crown
110*
What is involved with the treatment planning phase (3)
Establish diagnosis
Set objectives
Establish treatment sequence
Which ASA classification may require medical consult?
ASA 2
During which phase of treatment planning do you measure edentulous spaces?
Treatment planning stage
Describe the pre-prosthetic phase of treatment planning
Stop active disease
Move teeth
Rebuild gingival architecture
Which way do the dislodging forces work on a fixed partial denture?
Mesio-distally
Which direction do dislodging forces work on a single restoration?
Bucco-lingually
Where can you use a cantilever bridge?
Lateral maxillary incisor with no function
First premolar where both 2nd premolar and 1st molar are abutments
Minimum ferrule length
2mm
