very informative and easily discussed about provisional restoration

1. Presented by –
Dr Abdullah Al Zubair
Dr Rupanti Biswas
Dr Shakila Zaman Isita

2. Provisional crown on fixed partial dentures
are essential to successful prosthetic surgery.
The word provisional means established for
the time being, pending a permanent
restoration.
Unfortunately the term temporary is quite
often used which denotes something of little
value is unimportant and which is quite
opposite for a provisional restoration.

3. According to the glossary of prosthetic terms
it can be defined as a transitional restoration
that provides protection,stabilization,and
function before fabrication of a definitive
prosthesis.

4. 1. Protection:It protect the prepared tooth
from damage ,pulp from irritation and
checks,tongue ,lips from trauma .
2. Mastication.
3. Positional stability.
4. Esthetic for vital tooth
5. Provide diagnostic information

5.  Even though a definitive restoration can be
placed as soon as two weeks after tooth
preparation ,the provisional restoration must
satisfy important need of the patient and
dentist.
 An optimal provisional restoration must
satisfy many interrelated factors ,which can
be classified as-
i. Biological
ii. Mechanical
iii.Esthetic requirements

6. Biologic:
1.protect pulp
2.Maintain periodontal
health
3.Provide occlusal
compatibility
4.Maintain tooth
position
5.protect against
fracture
Mechanical:
1.Resist Functional
loads
2.Resist removal forces
3.Maintain
interabutment
alignment
Esthetic
1.Easily
contourable
2.color
compatibility
3.Translucency
4.Color stability

7. According to method of fabrication:
1.custom made restoration
2.preformed restoration
1.custom made restoration:
Advantages:
a. Minimum interference
b. A wide variety of materials can be used.
c. Helpful in evaluation the adequacy of tooth
reduction.By measuring the thickness of the
restoration the tooth prereration can be altered

8. Disadvantages:
a.Additional lab procedure involved.
b.Time consuming .
Materials:
i.Template and unfilled resin
ii.Template and composite resin
iii.Laboratory produce shell
iv.cast metal

9.  Preformed provisional restoration
Advantages:
Less time consuming .
Disadvantages:
a.Rarely satisfies the requirements of contour.it has to be
customized with self cure resin
b.Generally limited to single tooth preparetion
Materials:
i.Polycarbonate
ii.Cellulose acetate
iii.Aluminium and Tin-Silver
iv.Nickel -chromium

10. According to type of material used:
1.Resin based provisional restoration
Exp: Cellulose acetate
polycarbonate
poly-methyl methacrylate
Microfilled composite
2.Metal provisional restoration
Exp: Aluminium
Nickel-Chromium
Tin-Silver

11. Based on duration of use:
1.Short term temporary:For use upto 2 weeks.
2.Long term temporary:For use from 2 weeks to
a few months .

12. Short term temporary restoration
Indication: They are indicated after tooth preparation
FPD
Fabrication: Either by custom made resin or by
preformed crown
Polycarbonate or Aluminum crown are the most
commonly used short term temporary restoration

13. Long term temporary restoration
Indication: Long span posterior fixed partial denture,
Prolonged treatment time
If the patient is unable to avoid excessive force on the
prosthesis
Fabrication: Cast Metal

14. According technique of fabrication:
1.Direct Technique
2.Indirect Technique
3.Direct-Indirect Technique

15.  Explanation of direct Technique:
A direct provisional restoration with Bis Acryl composite -
Finally the restoration is finished, polished and cemented
After 10 minutes the overimpression is removed and the
polymerized composite restoration should be carefully traced out
Before the composite polymerizes, the over impression is reseated
in the patient mouth
The base and catalyst of the composite are mixed and loaded into
the over impression
The prepared tooth is coated with petrolatum
Tooth Preparation carried out
First, an over impression is made using addition silicone

17. Disadvantages:
a.Adverse pulpal or soft tissue reaction to monomer and increased
temperature
b.Allergic reaction
c.Locking of restoration into undercuts
d.Consuming chair time
Those potential problems can be avoided by these measures-
a.Remove provisional restoration from teeth while in plastic stage
b.Allow final polymerization to occur extraorally
c.Use water coolant
d.Use Reline technique

18. Explanation of indirect technique
Fabrication of an acrylic provisional restoration for a
posterior tooth-
Then monomer and polymer of resin is mixed in
dappen dish and placed into the over impression
Separating medium is painted on the plaster
cast
Then plaster is poured from the alginate
impression
Tooth preparation is carried out ,then alginate
impression of the prepared tooth is made
An over impression is made from the diagnostic
cast
Model preparation(defects such as missing cusp
should be filled)

19. Then finishing and polishing is done and cemented the
restoration with zine oxide eugenol
Remove the cast from plaster after about 30 minutes then
clean it
The cast is held in place with a rubber band
The cast is seated firmly in the over impression

21. Advantages:
a.Improved marginal accuracy.
b. prevention of pulpal and soft tissue irritation
from monomer and temperature.
c. reduce chair time
d. more comfortable for patient .
e. replacement restoration can be made without
having the patient present .
Disadvantages:
a. laboratory procedure required.
b.Dental auxillary required.

22. A preformed crown is checked for extarnal fit
and finish in the patient mouth
An impression of the prepared tooth surface is
made and a cast is poured
Then the selected preformed crown is
customized for the patient in the lab
The altered preformed crown is then placed on
the cast and the tissue sarface is contured using
resins
The final restoration is the customized one

24. Advantages:
a.chair side time is required
b.less heat is generated in the mouth .the volume
of resin used during lining is comparatively small.
c.contact between soft tissue and resin monomer is
minimized as compared to the direct procedure.
Disadvantages :
a.Adjustments are frequently needed to seat the
completely on the prepared tooth.this is the chief
disadvantage of direct-indirect technique .

25. 1.Lack of inherent strength: In long span
bridge, patient with bruxism reduced inter-
occlusal clearance.
2. Poor marginal adaptation.
3. Color instability may occur in larger
denture of use.
4. Poor wear properties.
5. Detectable odor emission. This is
considerable as resin is porous.
6. Inadequate bonding characteristics: Very
few temporary luting agents adhere well to
the tooth structure.

26. Although interim restoration are usually
intended for short- term use and then
discarded , they can be made to provide
pleasing aesthetics, adequate support and
good protection for tooth while maintaining
periodontal health. They may be fabricated
in the dental office from any of several
commercially available materials and by a
number of practical methods. The success of
fixed prosthodontics often depends on the
care with which the interim restoration is
designed and fabricated.