Flashcards in Final Deck (91)
Increasing a surface area that contacts the critical areas of a bite registration adds to that accuracy.
Should stained sclerotic dentin be removed if it is at the cavosurface?
Can salivary glands be stimulated by a painful stimulus?
How many variables define color?
Hue,Chroma and Value
If you look away and then back at a tooth and have trouble matching the color, what can you use as a guide?
The cervical third of the unrestored canine will give you the right hue
Roughness/surface texture of intaglio surface of restoration does what to retention?
Roughness increases retention
What are the 2 parameters that most crown and bridge cements are measured? How do they affect the cement?
Compressive strength, modulus of elasticity
Compressive strength goes up, cement is more retentive
Increases modulus of elasticity, increases retention
For a ferrule to be most effective, how tall should it be?
2mm is ideal
What are the three types of cements used in dentistry in order from strongest to weakest?
Strongest: Adhesive > Esthetic > Self Adhesive
With a dual cure esthetic resin cement (cure on its own), does light activation enhance the properties of the set cement at all?
Yes! Hit it with the light from all directions and make sure you get a deep cure.
Which stone expands the very least?
Mounting stone type 1
Minimum number of occluding units to have decent function? Opposing premolars count as how many occluding units? Opposing molars count as how many occluding units?
3, 1, 2
What are contraindications for a shortened arch?
Active periodontal diseases
Under age 40
Problems with TMJ or muscles of mastication
Severe class one or class to occlusal relationship
If you’re missing all occluding units on one side, this can cause issues (for example, if you didn’t have premolars or molars on one side)
Glass ionomer cement is more or less soluble than resin cement and zinc phosphate?
More soluble than resin
Less soluble than zinc phosphate
Solubility: Zinc phosphate > Glass Ionomer > Resin
*the better you finish your margins, and the closer they adapt, the less likely your cement will dissolve
What is the difference between RelyX luting plus and RelyX Unicem?
RelyX Unicem: Self Adhesive Resin Cement
RelyX Luting Plus: Resin modified glass ionomer
Either one can be used to cement a zirconia crown
What is the problem with excursive contacts on the inclines of posterior teeth?
Causes off-axis loading
Increase tendency for clenching, bruxing, grinding, etc because it increases muscle activity.
Create a centrum type contact to avoid the excursive contacts
- Cusp tip to flat receiving area!
What are the benefits of a well-made custom tray?
Less bulk of material and closer adaptation will improve accuracy of PVS
Higher tear strength
Do posterior or anterior teeth have proprioception?
Posterior teeth only
When bonding zirconia, why should you be cautious?
Retrievability is poor (too strong of a bond)
Use resistance and retention (cement/luting→ fills space between crown and tooth, no actual chemical bond)
You can go ahead and bond emax
How do parallel posts and taper posts transfer stress differently?
Parallel: stress is near apex
Tapered: stress is coronal
Posts and buildups - what 2 factors determines the longevity of the restoration more than any other factors?
Coronal tooth structure remaining
Occlusal prosthetic design of restoration (directs forces axially)
Is pulp chamber ok to anchor tooth?
Yes, better than a post
When removing existing crown:
Section it in half
Insert crown splitter to pry them off
Is silver a noble metal?
Ideal metal lingual clearance
No less than 1mm
Minimum thickness of metal for PFM
Why is full coverage crown more retentive than partial
All axial walls are involved
What is the purpose of the non-functional cusp bevel?
What are its dimensions?
Gets rid of that acute angle
0.3-0.7 mm wide
True or False: If you increase surface area of prep, it increase resistance and retention?
False. Resistance is not always increase (think vertical hight of axial wall being short on a very wide tooth
Retention is always increased with an increase of surface area