Important Info 2.3/2.4 Flashcards
Ideally, what is the max amount of porcelain thickness on pfm can be unsupported?
a. 1
b. 1.5mm
c. 2mm
d. 2.5mm
e. 3.mm
c. 2mm
What is false about zirconia
a. Tetragonal
b. Lithium disilicate
????- idk what its saying but heres some facts about zirconia
-has a polycrystalline structure
-resin bonding will NOT increase strength (will increase retention)
-can NOT be etched
-can use any cement
-shrinks 25% when fired
-transformational toughening (tetragonal –> monoclinic)
-wear friendly
-masks dark dentin
Which zirconia is most like emax
a. 3y
b. 5y
c. 7y
b. 5y
What is FALSE for this case? Had picture of slightly tipped second molar, missing 19, had two premolars
a. mesial convergence would increase retention
b. you don’t need to change your prep design because there is no second molar
c. risk exposure mesial pulp horn
d. Want less than 30 degrees different between molar and premolars
b. you don’t need to change your prep design because there is no second molar
What do you expect to see on your modified ridge lap pontic after coming back from the lab?
a. T-shaped gingival contact
b. Convex
c. Tissue blanching
d. Onnon keratinized tissue
a. T-shaped gingival contact
Picture of patient, says patient is 15 year old female with congenitally missing laterals. What is the best solution for her at this time? Said she is in MI, very little vertical overlap.
a. Two bridges
b. Two cantilevers with incisors
c. Resin bonded cantilever
d. Implants
c. Resin bonded cantilever
if deep bite (vertical overlap) do not do resin-bonded
What is true about CTE of metal and porcelain
a. Metal a lot lower than porcelain
b. Metal slightly lower than porcelain
c. Metal a lot higher than porcelain
d. Metal slightly higher than porcelain
e. As close as possible
d. Metal slightly higher than porcelain
What is happening in this picture?
a. Supraeruption
b. Drifting
c. Tilting
d. Occlusal interferences
e. All of the above
maybe a photo like this…
e. All of the above
What is false of connector
a. Needs to be 4x4
b. Buccal lingual height more important than occlusal gingival height
c. Same thickness for different materials
d. Connectors need to be smaller in anterior teeth
b. Buccal lingual height more important than occlusal gingival height
From the photo, What is an indicator for a FPD?
a. 50% tooth support
b. Not a lot of bone loss
c. Multiple edentulous spaces
d. Ante’s law negative number
b. Not a lot of bone loss
What is the ideal crown to root ratio
a. 1:1
b. 2:3
c. 3:2
d. 3:4
b. 2:3
What does not impact fpd ????
Opposite arch dentition
Missing canine which is true
a. Any fpd with missing canine is simple
b. Canine pontic in interbutment axis
c. Generally Weakest teeth are those abutments
d. Better prognosis for maxilla than mandible
c. Generally Weakest teeth are those abutments (lateral and 1st pm)
Picture of 4 unit posterior mand bridge. Says patient occludes on occlusal lingual. Where do you put retention grooves?
a. Mesial distal
b. Buccal lingual
c. Mesial buccal
d. Lingual distal
a. Mesial distal
Picture of pt with red line at gingiva around anterior crowns. What is likely causing this?
Base metal allergy
Why do you pick a base metal?
a. Bond strength
b. Increase strength
c. Allergy
b. Increase strength
Which is false
a. Flexure and connector height are directly proportional
b. Flexure and connector height are inversely proportional
c. Zirconia connector is 3x4 mm minimum
a. Flexure and connector height are directly proportional
What is true of sintering
a. Happens when cooling down
b. Happens below 500 degrees
c. More space between particles
d. Makes zirconia hard and smooth
d. Makes zirconia hard and smooth
540-610 degrees C
What is true for this case (picture had pier abutment)
a. Non rigid connector on distal of tooth
b. Middle tooth (4) is the one that will have problems
b. Middle tooth (4) is the one that will have problems
Pt wants zirconia crowns 6-11, what is true? Picture showed pt with very dark laterals
a. Zirconia can’t cover up the darkness of teeth
b. Pfz is a good option for strength and esthetics
b. Pfz is a good option for strength and esthetics
What can you do in this situation to improve the prognosis? Showed bridge with two PM pontics and a cantilever molar
a. Decrease size of pontic
b. Strong occlusal forces keep it in place
a. Decrease size of pontic
Missing lateral, what is false
a. Best abutment is incisor
b. Best abutment is canine
c. Good idea to have wrap around proximal tooth
d. Pontic Should be out of occlusion
a. Best abutment is incisor
MPa of enamel
300
Crack propagation question, which is false
a. Transformational toughening is for lithium disilicate and zirconia
b. Particles change from tetragonal to monoclinic
c. Volume increase retards crack
d. Polycrystalline structure something
a. Transformational toughening is for lithium disilicate and zirconia
CTE question- It was like porcelain CTE compared to metal CTE
a. Significantly lower
b. Slightly lower
c. Equal
d. Slightly higher
e. Significantly higher
b. Slightly lower
Picture of a person with a bridge and obviously resorbed bone / tissue. How long should you wait to make a final restoration to make sure this doesn’t happen?
a. 2 weeks
b. 6 weeks
c. 8 weeks
d. 12 weeks
d. 12 weeks
How thick is opaquing porcelain?
a. 0.3
b. 0.8
c. 1mm
d. 2mm
a. 0.3
What bonds to the oxide layer
Opaquing porcelain
How far should the occlusion be from the porcelain metal finish line?
1.5 mm
What is false about the connector
a. V shaped notch near the gingiva
b. Upside down U shaped connector with large radius
a. V shaped notch near the gingiva
You cannot etch…
zirconia (no glass)
Resin bonding helps with ___________ of zirconia
retention
not strength
True/false
Zirconia is wear friendly
True
doesnt wear teeth like porcelain
