10/23: Provisional Restorations Flashcards
this is a prosthesis desigend to enhance, stabilize, and or function for a limited amount of time
provisional
do you need a provisional if you mill in the office?
no
what are the functions of a provisional?
prevent sensitivity
prevent drifting
ability to heal
restore function to teeth
esthetics
diagnostic evaluation
what are the requirements of a provisional?
pulpal protection
positional stability
occlusal function
abilty to clean
marginal integrity
esthetics and phonetics
strength and retention
what positional stabilities are we looking for?
proximal contacts
occlusal contacts
inter-abutment stability with a bridge
if a temp fell off and patient comes back, what should you expect?
adjust teeth
open proximal contacts will cause
food and debris impaction
without good occlusal contacts, you will get
extrusion and need more adjustment
if your temporary is high, what can happen?
loss or breakage
should you have contacts with lateral or protrusive movements on the posterior teeth?
No
you want the margin fit as closs to the
finish line
the emergency profile should be
flat or slightly concave
what happens if you have a rough margin?
plaque accumulation and gingival inflammation
can bleeding gums be a challenge to take impressions or seat with?
Yes
what material do we use in the clinic?
bisacryl
what is the main issue with bis-acryl?
very brittle
do you need to continually place the temporary on the tooth when making adjustments?
yes, cause it will shrink
what forms the extenal and internal portions of the interim?
external = putty matrix
internal = preparation
what are the 2 types of interim restorations?
external surface forms (pre-fab)
directly on tooth or indirectly on cast
pre-fabricated crown forms are limited to what?
single units
fre-fabricated crown forms must be lined with
auto-polymerizing resin
Best when patient in your office with crown off and lost or broken tooth with not enough tooth to make a traditional matrix form
pre-fabricated crown form
these can be used for singles but required for multiple units
custom mulded interims
these stimulate planned restorations when used with diagnostic wax ups
custom molded interims
this is an example of what technique?
direct
this is an example of what technique?
indirect
what technique allows you to see multiple undercuts ahead of time?
indirect
what acrylic resins are commonly used?
PMMA
jet acrylic
these are powder/liquid formulations
acrylic resins
describe bis-acryl composite resins
Bis-GMA containing
chemical and light activated
if you have inadequate polymerization in PMMA what happens?
poor mechanical properties
if you have too little powder in PMMA, what happens?
loss of strength
if you have too much powder in PMMA, what happens?
poor handling and adaptation
benefits of PMMA?
good marginal fit
good strength
Polishes will
good durability
dis-advantages of PMMA
high exothermic
high shrinkage
toxic monomer
low abrasion resistance
the monomer and activator are
liquid
the filler and initiator are
powder
what are the dis-advantages with Bis-Acryl?
limited polishablility
no rubbery stage
high cost
brittleness
TEMPsmart is an example of
Bis-Acryl
2 types of provisional cements
Zinc oxide eugenol
non-eugenolTemp bond is an example of
Temp bond is an example of
zinc oxide eugenol
what are examples of non-eugenols?
ultratemp
smartemp
eugenol is a ____ for tooth
sedative
eugenol can inhibit
resin polymerization
is ZOE high strength?
no, low
Polycarboxylate cements have
low strength
glass-ionomer based cements are good because
longer term temporary use
resin cements are
translucent
in cementation, you mix
equal parts of base and catalyst
