Fixed Pros Flashcards
Symptoms of cracked cusp:
Pain with:
- Hot/cold stimuli
- Loading or release of biting pressure
- Sweet sensitive
- Sharp fleeting pain on biting
- May linger as a dull ache for 15-30 mins after a meal
Tests for cracked cusp syndrome:
- Discolouration
- Transillumination
- Staining (caries detector dye)
- Cold test
- Selective loading pressure over suspected cusps
What is the difference between simple, complex, compound and complicated tooth fractures
- Simple = enamel
- Complex = enamel and dentine
- Compound = pulp involvement
- Complicated = crown root
Retention form of fixed prostheses is influenced by:
- Degree of taper
- Total surface area for cement
- Roughness of tooth surface
Resistance form of fixed prostheses is enhanced by:
- Preparation length
- Preparation width
- Taper
- Prevention of rotation
- Limited path of insertion
What width do chamfers need to be for
a) gold
b) ceramic
c) PFM (shoulder)
a) 0.5mm
b) 1.0mm
c) 1.5mm
The aim of gingival retraction is to gain crevicular width of:
0.2mm
To achiee a crevicular width of 0.2mm, cord must remain in the crevice for an optimum of how long?
4 mins
The CR is the same at various OVD before translation
True or false
True
What is CR
Condylar position located in anterior superior position against the posterior slope of the articular eminence
What two skeletal classes won’t have anterior guidance in protrusive movements.
- Class III
- Class II Div I
What is a key change you need to do when preparing a partial coverage for multiple unit prosthesis?
Needs to have resistance to lateral forces so drop palatal margin to gingival level
List 5 indications for resin bonded bridges
- Replacement of lateral incisors and mandibular incisor
- Unrestored teeth
- Poor root angulation or insufficient bone for implant
- Light or no occlusal forces
- Periodontal splints
List 5 contra indications for resin bonded bridges
- Extensive past restoration
- Heavy occlusal load - bruxing
- Limited bonding surface
- Poor tooth morphology
- Shape and shade change of the abutment needed
Cantilever designed RBBs have a 5 year survival rate of:
91%
Resistance form in crown preparations:
a) Improved by increased taper
b) Is not as important as the type of cement used for stability
c) Does not relate to the height of the crown
d) Can be improved with additions to the prep such as mesial and distal grooves
e) Is the ability to withstand vertical dislodging forces
d) Can be improved with additions to the prep such as mesial and distal grooves
For an unbonded restoration, a prep height of at least mm is needed.
3mm
How much reduction is needed for ceramic onlay?
- 1.5mm occlusal
- 1mm axial
- 0.2mm cement thickness
5 indications for zirconia:
- Limited occlusal space
- Covering dark discolouration
- Isolation for reliable bonding is too dificult
3 benefits of good bond strength:
- Low sensitivity
- Less recurrant caries
- Less staining
10 year survival of veneers when bonded to enamel is:
91%
In what situation would you prep a veneer to slightly beyond the contact point?
Closing a diastema.
otherwise keep in front of contact so tooth is stable whilst veneer is made.
Prep for porcelain veneers should be how thick?
0.3 to 0.5mm
