Midterm Review Flashcards
Palodent should be placed:
1 mm above the margin of adjacent tooth
What does a cure thru matrix do?
achieves the best contours
When to re-etch?
- if contaminated
- if it doesn’t appear etched
How much should you break the facial contact for class III?
0.25 mm (to allow for matrix band and good esthetics)
What type of composites are used at UMKC?
nanohybrids
What is NOT true about an S-curve?
makes walls diverge
What do the methacrylate monomers in bulk fill do?
relieve stress
What do you use for a class III?
mylar strips
What is true about the smaller tip when light curing?
smaller tip = increased heat and output
Elastic modulus also means?
stiffness
Couples filler with resin (coupling agent)
silane
axiopulpal line angle is ____ in amalgam to improve
beveled; resistance
Camforquinone is a _____ and is activated by:
initiator; blue light
What would you recommend for a patient with sensitivity?
tooth paste with KNO3 (maybe glumma too)
T/F it is okay to leave unsupported enamel in a class III prep:
true (facial wall)
Order of composite restoration:
- etch
- bond
- fill
- finish
- polish
Reason for box only prep?
to conserve tooth structure
What class has the highest c-factor?
class I > class II > class III
Reason for doing flowable at the bottom of a box?
to improve gingival margin seal
What should you do if you have heavy contact on the lingual of a class III or class IV?
do not bevel lingual margin? Maybe sandpaper strips after too)
Main reason for etching is:
increase surface area and surface energy
Purpose of beveling gingival margin:
exposes enamel rods
What could result from composite sticking to a tool?
void
Order from softest to hardest:
cementum then dentin then enamel (hardest)
Increasing the filler in composite leads to:
- increased strength
- decreased shrinkage
Most esthetic for class III and class IV:
microfill (hybrid)
What do you do before putting on a rubber dam?
shade selection
What teeth do you isolate with rubber dam?
one tooth posterior and two teeth anterior
When you have two adjacent preps you should
prep the largest first, and then restore the smallest first
Incremental layers of composite creates:
less stress
Improper wedging can result in:
gingival inflammation
What restoration error would result in gingival irritation?
over contoured restoration
What is the reason to choose composite over amalgam?
patient wanting a tooth colored filling
Why do you want a good path of entry?
bonding will be better (maybe due to direction of enamel rods)
What should you consider when choosing between amalgam and composite?
- diet
- placement of caries
- ability to isolate
(Family history of MS is not a consideration)
Dentin adhesive bonding can best be described as:
collagen and resin interlocked intertubular dentin (hybrid layer)
Should the smear layer be removed?
yes
Palodent is best used for:
small class II composite
All of the following are differences between composite and amalgam except:
final occlusal position
Pt has a DO done on #4, and now has cold sensitivity and inflamed gums, what is likely the cause?
fluid in dentinal tubules
Lower polymerization shrinkage means lower:
c factor
bonded surfaces divided by unbonded surfaces =
c bond
In what tooth are you most likely to expose the pulp by going in with the long axis of the tooth?
mandibular first pre molar #28 (need a slanted prep)
Adhesive solvent that we use at UMKC:
Ethanol
Bonding agent ___ bonds to enamel. Bonding agent ____ bonds to dentin. Bonding agent ___ bonds to resin
micro mechanical
micro mechanical
chemical
collagen and resin from intertubular dentin:
hybrid layer
Tooth flexing and bending:
abfraction
Abraction primarily affects what portion of the tooth:
cervical
Is bonding agent hydrophilic or hydrophobic?
hydrophobic
Where is retention groove in class V prep placed?
occlusal axial angle
Prismless enamel is found:
cervical
What will prevent you from having a good contact in class II?
- sectional matrix
- pre-wedge
Where do you bevel for a class II?
- axiopulpal line angle
- gingival
- lingual wall
What leads to the most post-op sensitivity?
bulk fill
Why do you flare on the Cavosurface?
to expose the ends of the enamel rods
Why is it harder to bond to dentin than enamel?
dentin is more heterogenous
T/F You bevel to expose the SIDES of enamel rods:
false
Longevity of the tooth is also known as:
fracture toughness
Root surface caries are more commonly found on:
gingival to the contact
All of the following are reasons we have failure at the gingival portion of the box EXCEPT:
incremental fills instead of bulk
All of the following are indications of composite EXCEPT:
heavy occlusion on the contact
Adhesive ___ in the present of water
separates
Instead of beveling in dentin you:
90 degree butt margin
Key difference in composite and amalgam is:
bevel gingival floor
Why do we not use eugenol?
inhibits polymerization (also BHT)
not strong enough to etch enamel, only partially removes smear layer:
self-etching primer
Self etch systems contain
acid in the primer
T/F: if prep is deeper/closer to the pulp you place retention groove 1 mm farther axially:
false
Strength for bonding comes from :
collagen in intertubular dentin
T//F: You must put bonding in between every increment of composite:
false
Wider dentin tubules are near the:
pulp
Erosin is caused by:
chemicals (like lemons)
When doing a class III make sure you preserve the:
incisal contact
What is hybrid?
resin with collagen (or maybe its filler)
Where does decay expand rapidly?
DEJ
Where does adhesive bond best?
intertubular dentin
Where do you put retention groove in a class III?
gingival wall
Results in collapse of collage layer and reduced bond strength:
desiccating dentin
Which is not true about beveling?
removes layer of fluoride rich dentin
Opaque composite requires:
longer curing times (need for class II so light doesn’t shine through)
Which of the following has the highest flexural strength?
hybrid
If adhesive bond strength is less than polymerization strength:
restoration will debond
Component of resin matrix is
Bis GMA
Which fill has the best wear resistance?
microfill
What is true about class IV restorations?
you should extend composite past the enamel bevel
Which liner do you use if your class II went too deep?
CaOH (dycal)
On a class III, caries occur:
below the contact
Which of the following determines the success of a class II restoration?
good isolation
