SlideShare ist ein Scribd-Unternehmen logo
1 von 100
IMPRESSIONS
IN
FIXED PARTIAL
DENTURESINDIAN DENTAL ACADEMY
Leader in continuing dental education
www.indiandentalacademy.com
www.indiandentalacademy.com
INTRODUCTION
www.indiandentalacademy.com
 .
www.indiandentalacademy.com
 Well-fitting indirect restorations can only be made if
there are accurate casts of the oral tissues available,
made from high quality impressions.
 A good quality impression is only obtained when we
have a thorough knowledge of materials, their
properties, and techniques for their best manipulation.
www.indiandentalacademy.com
TERMINOLOGIES
www.indiandentalacademy.com
IMPRESSION : A negative likeliness or copy
in reverse of the surface of an object; an
imprint of the teeth and adjacent structures for
use in dentistry – G.P.T-8
IMPRESSION TRAY : A receptacle into
which suitable impression material is placed to
make a negative likeliness (or) a device that is
used to carry, confine, and control impression
material while making impression– G.P.T-8
www.indiandentalacademy.com
IMPRESSION MATERIAL: Any substance or
combination of substances used for making an
impression or negative reproduction. – G.P.T-
8
IMPRESSION TECHNIQUE : A method and
manner used in making a negative likeness. –
G.P.T-8
www.indiandentalacademy.com
HistoryHistory
 Philip Pfaff-1756
 First described taking impression with softened
wax
 Christopher Francois Delabarre-1820
 Introduced the metal impression tray
 Chapin Haris-1853
 First used Plaster of Paris for making impressions
 Charles Stent-1857
 Introduced the first impression compound
www.indiandentalacademy.com
 Sears-1937
 First used agar hydrocolloids for recording
crown impressions.
 United States-1945
 Introduced alginate during World War II.
 SL Pearson-1955
 Developed synthetic rubber base impression
materials
 Polysulfide- Late 1950’S
 First developed as an industrial sealant.
www.indiandentalacademy.com
 Condensation Silicone- Early 1960’s
 Addition Silicone-1970’s
 Polyether- Late 1970’s
 Polyether Urethane Dimethacrylate - Late
1980’s
www.indiandentalacademy.com
Properties Of An Ideal Impression
1)Complete plasticity before cure
2)Sufficient fluidity to record fine detail.
3)The ability to wet the oral tissues.
4) Dimensional accuracy.
5)Dimensional stability.
6)Complete elasticity after cure.
7)Optimal stiffness. www.indiandentalacademy.com
Impression Materials Used In F.P.D
1)Hydrocolloid impression material
a) Reversible hydrocolloid
b) Irreversible hydrocolloid
2)Elastomeric impression materials
a) Polysulfide
b)Addition silicone
c) Condensation silicone
d)Polyether
www.indiandentalacademy.com
AGAR (reversible hydrocolloid)
History
 In 1925, Alphous Poller of Vienna was granted a
British patent for a totally different type of
impression material called as Negacol
 Later Poller's 'Negacoll’ was modified and
introduced to the dental profession as 'Dentacol’
in 1928.
www.indiandentalacademy.com
Example
 Slate Hydrocolloid (Van R)
 Cohere
 Superbody
 Super syringe
www.indiandentalacademy.com
 Available as - syringe and tray material
Composition:
Component Function Composition
Agar Brush – heap structure 13 – 17%
Borax Strength 0.2 – 0.5%
Potassium Sulfate Gypsum hardener 1.0 – 2.0%
Water Reaction 80%
Alkyl Benzoate Prevent growth of mold in
impression material during
storage.
0.1%
Color and Flavors Taste & appearance Trace
www.indiandentalacademy.com
 Setting reaction:
Agar hydrocolloid (hot) Agar hydrocolloid (cold)
(Sol) (Gel)
Cool to 43 C
Heat to 100 C
Manipulation:
Three chamber conditioning unit
(1) Liquefy at 100 0
C for 10 minutes converts
gel to sol
(2) Store at 65 – 68 0
C place in tray
(3) Temper at 46 0
C for 3 minutes
seat tray
(4) cool with water at 20 0
C for 3 minutes
converts sol to gel
www.indiandentalacademy.com
Advantages
 Accurate reproduction of surface detail
 Hydrophilic
 displace moisture, blood, fluids
 Inexpensive
 No custom tray or adhesives
 No mixing required
www.indiandentalacademy.com
Disadvantages
 Initial expense
 special equipment
 Material should be prepared in advance
 Tears easily
 Dimensionally unstable
 Pour immediately
 Single cast
 Difficult to disinfect
www.indiandentalacademy.com
ALGINATE (irreversible hydrocolloid)
 Alginate was developed as a substitute for agar when
the agar impression material became scarce because
of World war II (Japan was a prime source of agar).
Examples
 Zelgan, jeltrate (Dentsply)
 Coe Alginate (GC America)
 Integra(kerr)
www.indiandentalacademy.com
Composition
Component Function Weight percentage
Na / Potassium
alginate
Soluble alginate 15
Calcium sulfate
dihydrate
Reactor 16
Potassium titanium
Fluoride
Accelerator 3
Zinc oxide Filler particles 4
Diatomaceous earth Filler particles 60
Sodium phosphate Retarder 2
www.indiandentalacademy.com
Setting reaction: (gelation process)
2 Na3PO4 + 3 CaSO4 Ca3(PO4)2 + 3 Na2SO4
Na alginate + CaSO4 Ca alginate + Na2SO4
(powder) (gel)
H2O
www.indiandentalacademy.com
Modified alginates
 Alginates modified by the incorporation of
silicone polymers (paste form)
 Dustless alginate - glycerin incorporated to
agglomerate the particles.
 Making the powder denser so that no dust is
formed when the lid is opened after tumbling.
www.indiandentalacademy.com
NEWER ALGINATES
 Kromopan 100.
manufactured by LASCOD
 MILLENIUM ALGIN is
considered an alginate of
new generation alginate.
 The impression can be
stored for many hours in a
Long Life Bag before
casting the model without
undergoing any change for
over 100 hours
www.indiandentalacademy.com
AUTOMIX DISPENSING: (Alginate
from Kerr international)
 No hand mixing. Eliminates
mess and cleanup. Saves time and
material.
 Delivery options. Cartridge or
Volume™ auto mix dispensing.
 Impressions remain stable. You
can pour immediately or when
it’s convenient. Impressions
retain dimensional stability for
months.
www.indiandentalacademy.com
Manipulation
www.indiandentalacademy.com
Mechanical mixing devices
www.indiandentalacademy.com
Advantages:
 Inexpensive
 Easy to use
 Hydrophilic
 displace moisture, blood, fluids
 Stock trays
www.indiandentalacademy.com
Disadvantages:
 Tears easily
 Dimensionally unstable
 immediate pour
 single cast
 Lower detail reproduction
 unacceptable for working cast of fixed
prosthodontics
 High permanent deformation
 Difficult to disinfect
www.indiandentalacademy.com
NON AQUEOUS ELASTOMERIC
IMPRESSION MATERIALS
 These are Synthetic rubbers.
 These mimic natural rubber (scarce during World
War II)
 Initially called rubber impression materials
 Currently referred as elastomers or elastomeric
impression materials.
www.indiandentalacademy.com
www.indiandentalacademy.com
Polysulfide
 The first elastomer used
for dental impressions
Examples
 Permlastic (Kerr)
 Omni-Flex (GC America)
– copper hydroxide
system
 Coe-flex( GC America)
www.indiandentalacademy.com
 Available in 3 viscosities,
 light body and medium body ,heavy body.
www.indiandentalacademy.com
Manipulation
 With the proper lengths of the two pastes squeezed
onto a mixing pad or glass slab, the catalyst paste is
first collected on a stainless steel spatula and then
distributed over the base, and the mixture is spread
out over the mixing pad.
 The mass is then scraped up with the spatula blade
and again smoothed out.
www.indiandentalacademy.com
 If sufficient force is applied and spatulation is
performed rapidly, the material will seem thinner
and easier to handle. This phenomenon is known
as pseudoplasticity.
 Most accurate impressions are made using custom
acrylic trays because of uniform thickness of the
material.
www.indiandentalacademy.com
Advantages Disadvantages
 Long working time
 High tear resistant
 inexpensive to use
 Long shelf life
Requires a custom tray
Must be poured in
stone immediately
Potential for
significant distortion
Odor offends patients
Messy and stains
clothes
Second pour is less
accurate
www.indiandentalacademy.com
SILICONES
www.indiandentalacademy.com
CONDENSATION SILICONE
 Condensation reaction – a polymerization reaction in which
the polymer chains grow simultaneously and a reaction
byproduct is ethanol
Available In Three Viscosities:
 Light body
 Medium body
 Putty body
Supplied as:
 Paste – two pastes in collapsible tubes
 Putty – jars
www.indiandentalacademy.com
Examples:
 Speedex
(Coltene/Whaledent)
 Primasil (TISS Dental)
 Accoe (GC-Amer)
 Xantopren (Unitek)
 Elasticon (Kerr)
www.indiandentalacademy.com
Composition:
Composition Components Function
Base paste Hydroxyl terminated
polydimethyl siloxane
prepolymer
undergoes cross linking
to form rubber
Silica Filler
Reactor Orthoethyl Silicate Cross linking agent
Stannous octate Catalyst
www.indiandentalacademy.com
Advantages:
 Better elastic properties
 Clean, pleasant
 Stock tray
 Good working and
setting time
Disadvantages:
Permanent deformation –
high – 1-3%
Poor dimensional stability
high shrinkage
 Hydrophobic
www.indiandentalacademy.com
ADDITION SILICONES
 Frequently called polyvinylsiloxane or vinyl
polysiloxane impression materials.
Supplied in 4 viscosities
 Light body
 Medium body
 Heavy body
 Putty
www.indiandentalacademy.com
Examples:
 Extrude (Kerr)
 Express (3M/ESPE)
 Aquasil (Dentsply )
 Virtual (Ivoclar Vivadent)
www.indiandentalacademy.com
Composition:
Components Function
Base paste Hydroxyl terminated
polymethyl siloxane
prepolymer
Undergoes cross linking
to form rubber
Colloidal silica Filler
Reactor Polyvinyl silicone
prepolymer
Colloidal silica Filler
Chloroplatinic acid Catalyst
www.indiandentalacademy.com
Advantages:
 Excellent reproduction of
surface details
 Highly accurate
 High dimensional stability
 pour up to one week
 Stock or custom trays
 Multiple casts
 Easy to mix
 Pleasant odor
Disadvantages:
 Expensive
 Short working time
 Lower tear strength
 Possible hydrogen gas
release
www.indiandentalacademy.com
POLYETHER
 Introduced in Germany in late 1960s.
Available as
 Base and accelerator in collapsible tubes.
 The accelerator tube is usually smaller.
 Earlier supplied in single viscosity.
 A third tube containing a thinner was provided.
Available in 3 viscosities
 Light body
 Medium body
 Heavy body
www.indiandentalacademy.com
Examples
 Impregum F (3M/ESPE)
 Permadyne (3M/ESPE)
 Pentamix (3M/ESPE)
 P2 (Heraeus Kulzer)
 Polygel (Dentsply )
www.indiandentalacademy.com
www.indiandentalacademy.com
Advantages
 Highly accurate
 Good dimensional
stability
 hydrophilic
 Good surface detail
 Pour within one week
 Multiple casts
 Good wettability
 Good shelf life
Disadvantages
Expensive
Short working time
Rigid
difficult to remove from
undercuts
Bitter taste
Low tear strength
Absorbs water
- changes dimension
- Leaches components
www.indiandentalacademy.com
Impression Techniques
 1. Stock tray technique/putty wash technique
- Double mix
- Single mix
 2. Custom tray technique
- Single mix
- Double mix
 3. Closed bite double arch technique
 4. Copper band technique
 5. Reversible hydrocolloid technique
www.indiandentalacademy.com
STOCK TRAY IMPRESSION
TECHNIQUE (Putty wash technique):
Mixing method: Double mix and single mix
Procedure :
 Place patient in supine position.
 Select tray type based on relative need for
retention and personal preference.
 Select tray shape and size based on patients arch
shape and size.
www.indiandentalacademy.com
 Coat the tray with adhesive on
the inside and rim.
 Mix the high viscosity putty
impression material according to
manufacturer’s instructions.
 Roll putty into elongated
cylinder.
 Insert into the stock impression
tray.
www.indiandentalacademy.com
 Cover putty with the manufacturer’s
spacer (a sheet of polyethylene)
 Insert and seat the tray with a rocking
motion.
 Hold and wait until initial set.
 Remove from the mouth with minimal
sideward movement.
 Wait and test for final set with the
clinical final set, which is when a finer
nail impression rebounds completely.
 Peel off the spacer.
 Remove excess impression material with
a sharp knife.
www.indiandentalacademy.com
MAKING FINAL IMPRESSION:
 Choose a large mixing pad
approximately six by eight
inches.
 Choose a spatula that is long
enough to pick up the mixed
impression material, yet
sufficiently pliable to mix the
material against the pad.
www.indiandentalacademy.com
 Mix the low-viscosity,
impression material according to
manufacturer’s instructions.
 First use a circular motion,
joining the two strands. Then a
figure eight motion to blend and
flatten the mixture onto the
mixing pad.
 While flattening the mixture,
limit the number of times of
lifting the spatula from the pad,
this reduces the number of voids
in the mixture.
www.indiandentalacademy.com
 Load the low viscosity impression
material on to a syringe .
 Syringe in the inaccessible area
first eg disto lingual line angle.
 Seat the tray .
 Wait for the final set.
 Remove the tray parallel to the
preparation path of withdrawal.
 The impression is evaluated for the
finish lines and for any distortion
and tear.
www.indiandentalacademy.com
SINGLE MIX TECHNIQUE:
 For the stock tray Single mix insert the low viscosity
impression material into the prepared area
 Putty material is loaded into the stock tray
 Position the tray over the arch.
 Seat from posterior to anterior, allowing the excess to
extrude anteriorly.
 Apply force in a vertical direction until further seating is
impossible.
 Evaluate final position and adjust tray quickly if necessary.
www.indiandentalacademy.com
EVALUATING FINAL
IMPRESSION
 Elastomeric material should be
present 0.5 mm beyond visible
finish line.
 Note presence of bur marks, the
junction of smooth root surface,
and continuous finish line.
 There should be no shiny
smooth areas; if present, they
suggest moisture contamination.
 There should be no tray show-
though in any areas of the
impression except at tissue
stops.
www.indiandentalacademy.com
 There must be no voids present,
they suggest mixing problems or
contamination.
 There should be no thin areas
leaving the finish line unsupported.
These areas distort under the weight
of the stone.
www.indiandentalacademy.com
Custom Tray Fabrication For Elastomeric
Impression
1)Mark the border of the
tray on the diagnostic
cast with a pencil
approximately 5mm
apically to crest of the
free gingiva.
www.indiandentalacademy.com
2)Adapt a wax spacer to the
diagnostic cast two layers
for 2.5mm thickness
approximately.
www.indiandentalacademy.com
Tray Stops
www.indiandentalacademy.com
3)Apply a layer of tinfoil over
the wax.
4)Mix autopolymerizing acrylic
resin according to manufacturers
recommendation
5)Adapt the resin to the cast
when in dough stage.
www.indiandentalacademy.com
Tray handle is made
Borders are trimmed and the tray is polished
www.indiandentalacademy.com
Lateral wings can be made which will help in easy
removal of the tray
www.indiandentalacademy.com
Prepare syringe:
 Lubricate the syringe lightly.
 Measure arch length of tray to guide in dispensing the
amount of elastomer. (Dispense one time the length
of the tray for the low viscosity elastomer).
www.indiandentalacademy.com
Making the final impression.
Medium or high viscosity is used in
the tray and low viscosity in the syringe.
The low viscosity material syringed in
the prepared site.
The high viscosity material is placed
in the custom tray and seated in the
mouth.
www.indiandentalacademy.com
The impression is removed and
evaluated.
www.indiandentalacademy.com
Close Bite Double Arch Method
synonyms :dual quad tray, double arch ,
triple arch , accu -bite ,closed mouth impression.
Requirements
The articulator should provide for a positive stop or there should
be sufficient teeth to maintain the vertical dimension.
There should be sufficient space distal to the terminal tooth in
the arch to allow tray approximation.
www.indiandentalacademy.com
Advantages
maximum intercuspation position is captured.
Less impression material is needed.
Less gagging may occur.
Disadvantages
The tray is not rigid .
Limited to one casting per quadrant .
The distribution of impression material is not uniform
www.indiandentalacademy.com
Technique
Evaluate the fit of the tray in the
patients mouth.
Observe the complete bilateral closure
and the patients comfort.
Practice till the patient is familiar with
the task.
www.indiandentalacademy.com
Making the final impression
 Mix the low viscosity material and
load the syringe
 The high viscosity material is used in
the tray.
 After the low viscosity material is
syringed the tray is positioned on the
arch.
 Instruct the patient to close the mouth
and observe for the interdigitation on
the opposite arch.
 Wait for the material to set .
www.indiandentalacademy.com
Instruct the patient to open the
mouth remove the tray by
applying equal pressure bilaterally.
Evaluate the impression.
www.indiandentalacademy.com
Copper Band or Tube Method
The copper band is used to salvage an impression of multiple
preparation where there is only vague margins on one or two
preparation that are not adequately replicated in the impression.
Fitting of the copper band to preparation
A copper band is selected and annealed by heating on a flame
and quenching in alcohol.
Mark the finish line with the explorer and round off the edges.
evaluate the fit and cut orientation hole on facial surface .
www.indiandentalacademy.com
Copper band with orientation holes
www.indiandentalacademy.com
Copper band contoured
www.indiandentalacademy.com
Evaluating the fit of the copper band
The circumference of the copper
band must be such that it will fit
over the preparation and still
project into the gingival crevice.
An oversize band should not be
used since it will impinge on the
gingival tissues.
www.indiandentalacademy.com
Making the compound plug
The green stick compound is heated over the Bunsen flame .
Insert the warm compound mass to fill approximately the top
third of the copper band.
Seat and orient on to preparation and compress excess in to the
band.
The compound should just touch the occlusal surface .
Remove and evaluate the impression, only the occlusal surface
should be impressed.
Remove 0.2mm of the compound to create space for the heavy
body poly vinyl silicone.
Drill a hole through the centre of the compound plug.
www.indiandentalacademy.com
Making the impression.
Coat the internal surface sparingly with adhesive .
Clean and isolate the preparation.
Mix heavy viscosity material and inject in to the band and
position it on the tooth.
Wait for the material to set remove the band and inspect the
impression
www.indiandentalacademy.com
Copper band with the final impression
www.indiandentalacademy.com
Reversible hydrocolloid technique
This impression technique requires a special conditioning unit
which consists of 3 thermostatically controlled water baths.
1. A liquefaction bath .
2.A storage bath .
3.A tempering bath.
www.indiandentalacademy.com
Rimlock trays with stops
www.indiandentalacademy.com
Procedure
Select the correct size of water cooled impression trays.
Place small modeling compound or prefabricated stops in the
tray to prevent over seating .
Fill the impression tray with heavy bodied material from the
storage bath and place it in the tempering bath
Load the syringe material in the syringe and replace it in the
storage bath.
Carefully remove the retraction cord and flood the tooth with
water.
www.indiandentalacademy.com
Inject the syringe material on the tooth cover the entire tooth.
Remove the impression tray from the bath wipe with the gauze
and place it in the mouth.
After seating cold water is circulated through the tray until the
impression material is set.
Remove the impression with a rapid motion, wash with cold
water ,evaluate for accuracy.
www.indiandentalacademy.com
Final impression in reversible hydrocolloid
www.indiandentalacademy.com
Laminate Technique (or) Agar
Alginate Combination Technique
 After injecting the syringe agar on to
the area to be recorded, an impression
tray containing a mix of chilled
alginate that will bond with the
syringe agar is positioned on it.
 The alginate gels by a chemical
reaction, whereas the agar gels by
means of contact with the cool
alginate rather than the water
circulating through the tray.
www.indiandentalacademy.com
Advantages
1. Less air bubbles
2. Water cooled trays are not required
3. It sets faster than the regular agar technique.
www.indiandentalacademy.com
Wet Field Technique
 This is relatively new technique
which has become popular.the areas
to be recorded are actually flooded
with warm water.
 Then the syringe material is
introduced quickly, liberally and in
bulk to cover the occlusal and/or
incisal areas only.
 while the syringe material is still
liquid, the tray material is seated.
www.indiandentalacademy.com
 The hydraulic pressure of the
viscous tray materials forces the
fluid syringe hydrocolloid down
into the areas to be recorded.
 This motion displaces the syringe
materials as well as blood and
debris throughout the sulcus
www.indiandentalacademy.com
The matrix impression system
Gus J. Livaditis jpd 1998, vol 79,issue 2
 The system uses a custom matrix to control the sulcular
environment and to deliver the impression material
subgingivally . It also incorporates the attributes of
traditional impression methods and overcomes partial the
deficiencies of impression making such as registration of
the subgingival Margins, gingival retraction and relapse,
hemostasis and sulcular cleaning, strengthening the
sulcular flange of impression and simplification for
making complex impressions.
www.indiandentalacademy.com
The system uses three impression materials
 1.A suitable elastomeric semi rigid material to form the
matrix.
 2. A high viscosity elastomeric impression material which
will preferably bond to the matrix forming material,
required to make an impression of the preparation of the
matrix
 3. A stock tray with medium viscosity elastomeric
impression material to pick up the matrix impression and
remaining arch not covered by the matrix.
 Carrier for matrix forming material, it may be either
custom made or stock available.
www.indiandentalacademy.com
Clear plastic carrier selected from
assortment of premade forms.
Matrix is made in carrier with polyvinyl siloxane material before soft tissue is retracted.
Immediately after tooth preparation
and before any retraction procedures
www.indiandentalacademy.com

Black Lines Indicate Sulcular extension.
Thick red line indicates crest of gingiva.
Two black marks point out proximal contacts
that must be relieved.
Slender bur or knife edged rubber
wheel used to enlarge interproximal
embrasures.
Matrix should extend one half to two thirds of tooth
beyond prepared teeth and close to gingival crest.
www.indiandentalacademy.com
syringe is used to fill matrix with high
viscosity impression material.
Matrix impression is seated with
light pressure.
Stock tray filled with medium viscosity impression material is seated over matrix
impression before matrix material polymerizes.
www.indiandentalacademy.com
REVIEW OF LITERATURE
 Nachum Samet DMD, Michael Shohat DMD, Alon Livny
DMD and Ervin I. Weiss DMD: A clinical evaluation of fixed
partial denture impressions; J Prosthet Dent, volume 94,
issue 2, August 2005, pages 112 – 117: This study evaluated the
quality of impressions sent to commercial laboratories for the
fabrication of fixed partial dentures (FPD) by describing the
frequency of clinically detectable errors and by analyzing
correlations between the various factors involved. Within the
limitations of this study, impressions made with polyethers had
the most detectable errors, followed by condensation-type
silicones. The high frequency of detectable errors found in
impressions sent for FPD fabrication is of concern.
www.indiandentalacademy.com
 Hung SH, Purk JH, Tira DE, Eick JD : Accuracy of one-step
versus two-step putty wash addition silicone impression technique;
J Prosthet Dent 1992 May; 67(5):583-9: This study compared the
accuracy of one-step putty wash with two-step putty wash impression
techniques. Five addition silicone impression materials-Mirror 3 (MR),
Mirror 3 Extrude (ME), Express (E), Permagum (P), and Absolute (A)--
were tested. A stainless steel model containing two full-crown
abutment preparations was used as the positive control. Five
replications for one-step and two-step putty wash impressions of the
master model were made for each test material. Accuracy of the
materials was assessed by measuring six dimensions on stone dies
poured from impressions of the master model. Accuracy of addition
silicone impression material is affected more by material than
technique. Accuracy of the putty wash one-step impression technique
was not different from the putty wash two-step impression technique
except at one of the six dimensions where one-step was more accurate
than two-step. Mirror 3 putty wash two-step impression presented less
distortion than Mirror 3 Extrude putty wash one-step or two-step
impression.
www.indiandentalacademy.com
 Nissan J, Laufer BZ, Brosh T, Assif D : Accuracy of three
polyvinyl siloxane putty-wash impression techniques; J
Prosthet Dent. 2000 Feb; 83(2):161-5; This study assessed
the accuracy of 3 putty-wash impression techniques (1) 1-step
(putty and wash impression materials used simultaneously);
(2) 2-step with 2-mm relief (putty first as a preliminary
impression to create 2-mm wash space with prefabricated
copings. In the second step, the wash stage was carried out);
and (3) 2-step technique with a polyethylene spacer (plastic
spacer used with the putty impression first and then the wash
stage). using the same impression material (polyvinyl
siloxane) in a laboratory model. For each technique, 15
impressions were made of a stainless steel master model that
contained 3 complete crown abutment preparations, which
were used as the positive control. Accuracy was assessed by
measuring 6 dimensions on stone dies poured from
impressions of the master model.
CONCLUSION: The polyvinyl siloxane 2-step, 2-mm, relief
putty-wash impression technique was the most accurate for
fabricating stone dies.
www.indiandentalacademy.com
SUMMARY
A good impression is an exact replica of each prepared tooth and
should include adequate amount of the unprepared surfaces
adjacent to the margin.
Impression technique and material should be selected on the basis
of biologic factor dictated by the anatomy and the physiology of
the mouth dictated by the orofacial tissues. Even though there are
innumerable techniques and procedure for impression making ,it is
the responsibility of the dentist to select the best possible procedure
based on sound knowledge , for achieving the best possible result
for the patient.
www.indiandentalacademy.com
REFERENCES
 1.Phillips science of dental materials – 11th
edition – Anusavice
 2.fundamentals of fixed prosthdontics- 3rd
edition Herbert T.Shillingburg
 3.Dental Materials – E. C. Coombe
 4.Applied Dental Materials – 8th Edition –
McCabe
 5.Contemporary Fixed Prosthodontics – 3rd
edition Stephen F.Rosenstiel
www.indiandentalacademy.com
1.Nachum Samet DMD, Michal Shohat DMD, Alon
Livny DMD and Ervin I. Weiss DMD: A clinical
evaluation of fixed partial denture impressions; J
Prosthet Dent, volume 94, issue 2, August 2005, pages
112 – 117.
2.Hung SH, Purk JH, Tira DE, Eick JD : Accuracy of
one-step versus two-step putty wash addition silicone
impression technique; J Prosthet Dent. 1992 May;
67(5):583-9.
3. Laufer BZ, Brosh T, Assif D : Accuracy of three
polyvinyl siloxane putty-wash impression techniques; J
Prosthet Dent. 2000 Feb; 83(2):161
www.indiandentalacademy.com
Thank youFor more details please visit
www.indiandentalacademy.com
www.indiandentalacademy.com

Weitere ähnliche Inhalte

Was ist angesagt?

Relining and Rebasing
Relining and RebasingRelining and Rebasing
Relining and RebasingAnuja Gunjal
 
bite registration for fixed Prosthodontic restoration
bite registration for fixed Prosthodontic restorationbite registration for fixed Prosthodontic restoration
bite registration for fixed Prosthodontic restorationBotan Khafaf
 
Digital impressions
Digital impressions Digital impressions
Digital impressions Navreet Bajwa
 
6. final impression techniques for removable partial dentures
6. final impression techniques for removable partial dentures6. final impression techniques for removable partial dentures
6. final impression techniques for removable partial denturesAmal Kaddah
 
Provisional restoration in fixed partial denture
Provisional restoration in fixed partial dentureProvisional restoration in fixed partial denture
Provisional restoration in fixed partial denturebhuvanesh4668
 
Impression techniques in complete denture
Impression techniques in complete dentureImpression techniques in complete denture
Impression techniques in complete dentureNikitaChhabariya
 
Temporary removable partial dentures
Temporary removable partial denturesTemporary removable partial dentures
Temporary removable partial denturesAmal Kaddah
 
Luting agents and cementation
Luting agents and cementation Luting agents and cementation
Luting agents and cementation Cing Sian Dal
 
journal club presentation on prosthodontics
journal club presentation on prosthodonticsjournal club presentation on prosthodontics
journal club presentation on prosthodonticsNAMITHA ANAND
 
Indications contraindications and classification of bridges/endodontic courses
Indications contraindications and classification of bridges/endodontic coursesIndications contraindications and classification of bridges/endodontic courses
Indications contraindications and classification of bridges/endodontic coursesIndian dental academy
 
Soft liners and tissue conditioners
Soft liners and tissue conditionersSoft liners and tissue conditioners
Soft liners and tissue conditionersDHANANJAYSHETH1
 
IMPRESSION MATERIALS PROSTHODONTICS
IMPRESSION MATERIALS PROSTHODONTICS IMPRESSION MATERIALS PROSTHODONTICS
IMPRESSION MATERIALS PROSTHODONTICS SUBHRAKANTI PANDIT
 
Resin bonded prosthesis /certified fixed orthodontic courses by Indian dental...
Resin bonded prosthesis /certified fixed orthodontic courses by Indian dental...Resin bonded prosthesis /certified fixed orthodontic courses by Indian dental...
Resin bonded prosthesis /certified fixed orthodontic courses by Indian dental...Indian dental academy
 
Horizontal jaw relation in complete denture
Horizontal jaw relation in complete dentureHorizontal jaw relation in complete denture
Horizontal jaw relation in complete dentureVinay Kadavakolanu
 
Gothic arch tracing/prosthodontic courses
Gothic arch tracing/prosthodontic coursesGothic arch tracing/prosthodontic courses
Gothic arch tracing/prosthodontic coursesIndian dental academy
 
Impressions for fpd/ implant dentistry course
Impressions for fpd/ implant dentistry courseImpressions for fpd/ implant dentistry course
Impressions for fpd/ implant dentistry courseIndian dental academy
 
recent advances in impression materials
recent advances in impression materialsrecent advances in impression materials
recent advances in impression materialsramkoti reddy
 

Was ist angesagt? (20)

Relining and Rebasing
Relining and RebasingRelining and Rebasing
Relining and Rebasing
 
bite registration for fixed Prosthodontic restoration
bite registration for fixed Prosthodontic restorationbite registration for fixed Prosthodontic restoration
bite registration for fixed Prosthodontic restoration
 
Digital impressions
Digital impressions Digital impressions
Digital impressions
 
6. final impression techniques for removable partial dentures
6. final impression techniques for removable partial dentures6. final impression techniques for removable partial dentures
6. final impression techniques for removable partial dentures
 
Provisional restoration in fixed partial denture
Provisional restoration in fixed partial dentureProvisional restoration in fixed partial denture
Provisional restoration in fixed partial denture
 
Impression techniques in complete denture
Impression techniques in complete dentureImpression techniques in complete denture
Impression techniques in complete denture
 
Temporary removable partial dentures
Temporary removable partial denturesTemporary removable partial dentures
Temporary removable partial dentures
 
Luting agents and cementation
Luting agents and cementation Luting agents and cementation
Luting agents and cementation
 
journal club presentation on prosthodontics
journal club presentation on prosthodonticsjournal club presentation on prosthodontics
journal club presentation on prosthodontics
 
Indications contraindications and classification of bridges/endodontic courses
Indications contraindications and classification of bridges/endodontic coursesIndications contraindications and classification of bridges/endodontic courses
Indications contraindications and classification of bridges/endodontic courses
 
Soft liners and tissue conditioners
Soft liners and tissue conditionersSoft liners and tissue conditioners
Soft liners and tissue conditioners
 
Impression - RPD
Impression - RPDImpression - RPD
Impression - RPD
 
IMPRESSION MATERIALS PROSTHODONTICS
IMPRESSION MATERIALS PROSTHODONTICS IMPRESSION MATERIALS PROSTHODONTICS
IMPRESSION MATERIALS PROSTHODONTICS
 
Resin bonded prosthesis /certified fixed orthodontic courses by Indian dental...
Resin bonded prosthesis /certified fixed orthodontic courses by Indian dental...Resin bonded prosthesis /certified fixed orthodontic courses by Indian dental...
Resin bonded prosthesis /certified fixed orthodontic courses by Indian dental...
 
Horizontal jaw relation in complete denture
Horizontal jaw relation in complete dentureHorizontal jaw relation in complete denture
Horizontal jaw relation in complete denture
 
Types of Articulators
Types of Articulators Types of Articulators
Types of Articulators
 
Gothic arch tracing/prosthodontic courses
Gothic arch tracing/prosthodontic coursesGothic arch tracing/prosthodontic courses
Gothic arch tracing/prosthodontic courses
 
Complete dentures 7. final impressions
Complete dentures 7. final impressionsComplete dentures 7. final impressions
Complete dentures 7. final impressions
 
Impressions for fpd/ implant dentistry course
Impressions for fpd/ implant dentistry courseImpressions for fpd/ implant dentistry course
Impressions for fpd/ implant dentistry course
 
recent advances in impression materials
recent advances in impression materialsrecent advances in impression materials
recent advances in impression materials
 

Ähnlich wie Impressions for fpd / implant dentistry course

Impressions for fpd / implant dentistry course
Impressions for fpd / implant dentistry courseImpressions for fpd / implant dentistry course
Impressions for fpd / implant dentistry courseIndian dental academy
 
Recent advances in dental materials /certified fixed orthodontic courses by I...
Recent advances in dental materials /certified fixed orthodontic courses by I...Recent advances in dental materials /certified fixed orthodontic courses by I...
Recent advances in dental materials /certified fixed orthodontic courses by I...Indian dental academy
 
Recent advances in dental materials /certified fixed orthodontic courses by I...
Recent advances in dental materials /certified fixed orthodontic courses by I...Recent advances in dental materials /certified fixed orthodontic courses by I...
Recent advances in dental materials /certified fixed orthodontic courses by I...Indian dental academy
 
Recent advances in dental materials/dental crown &bridge course by Indian den...
Recent advances in dental materials/dental crown &bridge course by Indian den...Recent advances in dental materials/dental crown &bridge course by Indian den...
Recent advances in dental materials/dental crown &bridge course by Indian den...Indian dental academy
 
Recent advances in dental materials certified fixed orthodontic courses by In...
Recent advances in dental materials certified fixed orthodontic courses by In...Recent advances in dental materials certified fixed orthodontic courses by In...
Recent advances in dental materials certified fixed orthodontic courses by In...Indian dental academy
 
Elastic impression materials/ dentistry online
Elastic impression materials/ dentistry onlineElastic impression materials/ dentistry online
Elastic impression materials/ dentistry onlineIndian dental academy
 
Elastic impression materials/endodontic courses
Elastic impression materials/endodontic coursesElastic impression materials/endodontic courses
Elastic impression materials/endodontic coursesIndian dental academy
 
Impression materials in orthodontics/endodontic courses
Impression materials in orthodontics/endodontic coursesImpression materials in orthodontics/endodontic courses
Impression materials in orthodontics/endodontic coursesIndian dental academy
 
Materials used for maxillo facial construction2/endodontic courses
Materials used for maxillo facial construction2/endodontic coursesMaterials used for maxillo facial construction2/endodontic courses
Materials used for maxillo facial construction2/endodontic coursesIndian dental academy
 
2.impression material in orthodontics
2.impression material in orthodontics2.impression material in orthodontics
2.impression material in orthodonticsKaran Purohit
 
Impression materials/ dentist laboratory technician
Impression materials/ dentist laboratory technicianImpression materials/ dentist laboratory technician
Impression materials/ dentist laboratory technicianIndian dental academy
 
Impression materials and gingival tissue management
Impression materials and gingival tissue managementImpression materials and gingival tissue management
Impression materials and gingival tissue managementNivedha Tina
 
Impression materials /certified fixed orthodontic courses by Indian dental ac...
Impression materials /certified fixed orthodontic courses by Indian dental ac...Impression materials /certified fixed orthodontic courses by Indian dental ac...
Impression materials /certified fixed orthodontic courses by Indian dental ac...Indian dental academy
 
Elastic impression materials/ esthetic dentistry programs
Elastic impression materials/ esthetic dentistry programsElastic impression materials/ esthetic dentistry programs
Elastic impression materials/ esthetic dentistry programsIndian dental academy
 
Materials used for maxillo facial construction/ dental crown & bridge courses
Materials used for maxillo facial construction/ dental crown & bridge coursesMaterials used for maxillo facial construction/ dental crown & bridge courses
Materials used for maxillo facial construction/ dental crown & bridge coursesIndian dental academy
 
Elastic impression materials/cosmetic dentistry courses
Elastic impression materials/cosmetic dentistry coursesElastic impression materials/cosmetic dentistry courses
Elastic impression materials/cosmetic dentistry coursesIndian dental academy
 
Impression materials /certified fixed orthodontic courses by Indian dental ac...
Impression materials /certified fixed orthodontic courses by Indian dental ac...Impression materials /certified fixed orthodontic courses by Indian dental ac...
Impression materials /certified fixed orthodontic courses by Indian dental ac...Indian dental academy
 
Impression materials / dental implant courses by Indian dental academy 
Impression materials / dental implant courses by Indian dental academy Impression materials / dental implant courses by Indian dental academy 
Impression materials / dental implant courses by Indian dental academy Indian dental academy
 

Ähnlich wie Impressions for fpd / implant dentistry course (20)

Impressions for fpd / implant dentistry course
Impressions for fpd / implant dentistry courseImpressions for fpd / implant dentistry course
Impressions for fpd / implant dentistry course
 
Recent advances in dental materials /certified fixed orthodontic courses by I...
Recent advances in dental materials /certified fixed orthodontic courses by I...Recent advances in dental materials /certified fixed orthodontic courses by I...
Recent advances in dental materials /certified fixed orthodontic courses by I...
 
Recent advances in dental materials /certified fixed orthodontic courses by I...
Recent advances in dental materials /certified fixed orthodontic courses by I...Recent advances in dental materials /certified fixed orthodontic courses by I...
Recent advances in dental materials /certified fixed orthodontic courses by I...
 
Recent advances in dental materials/dental crown &bridge course by Indian den...
Recent advances in dental materials/dental crown &bridge course by Indian den...Recent advances in dental materials/dental crown &bridge course by Indian den...
Recent advances in dental materials/dental crown &bridge course by Indian den...
 
Impression materials
Impression materialsImpression materials
Impression materials
 
Recent advances in dental materials certified fixed orthodontic courses by In...
Recent advances in dental materials certified fixed orthodontic courses by In...Recent advances in dental materials certified fixed orthodontic courses by In...
Recent advances in dental materials certified fixed orthodontic courses by In...
 
Elastic impression materials/ dentistry online
Elastic impression materials/ dentistry onlineElastic impression materials/ dentistry online
Elastic impression materials/ dentistry online
 
Elastic impression materials/endodontic courses
Elastic impression materials/endodontic coursesElastic impression materials/endodontic courses
Elastic impression materials/endodontic courses
 
Impression materials in orthodontics/endodontic courses
Impression materials in orthodontics/endodontic coursesImpression materials in orthodontics/endodontic courses
Impression materials in orthodontics/endodontic courses
 
Materials used for maxillo facial construction2/endodontic courses
Materials used for maxillo facial construction2/endodontic coursesMaterials used for maxillo facial construction2/endodontic courses
Materials used for maxillo facial construction2/endodontic courses
 
2.impression material in orthodontics
2.impression material in orthodontics2.impression material in orthodontics
2.impression material in orthodontics
 
Impression materials/ dentist laboratory technician
Impression materials/ dentist laboratory technicianImpression materials/ dentist laboratory technician
Impression materials/ dentist laboratory technician
 
Impression materials and gingival tissue management
Impression materials and gingival tissue managementImpression materials and gingival tissue management
Impression materials and gingival tissue management
 
Impression materials /certified fixed orthodontic courses by Indian dental ac...
Impression materials /certified fixed orthodontic courses by Indian dental ac...Impression materials /certified fixed orthodontic courses by Indian dental ac...
Impression materials /certified fixed orthodontic courses by Indian dental ac...
 
Elastic impression materials/ esthetic dentistry programs
Elastic impression materials/ esthetic dentistry programsElastic impression materials/ esthetic dentistry programs
Elastic impression materials/ esthetic dentistry programs
 
Materials used for maxillo facial construction/ dental crown & bridge courses
Materials used for maxillo facial construction/ dental crown & bridge coursesMaterials used for maxillo facial construction/ dental crown & bridge courses
Materials used for maxillo facial construction/ dental crown & bridge courses
 
Elastic impression materials/cosmetic dentistry courses
Elastic impression materials/cosmetic dentistry coursesElastic impression materials/cosmetic dentistry courses
Elastic impression materials/cosmetic dentistry courses
 
Impression materials /certified fixed orthodontic courses by Indian dental ac...
Impression materials /certified fixed orthodontic courses by Indian dental ac...Impression materials /certified fixed orthodontic courses by Indian dental ac...
Impression materials /certified fixed orthodontic courses by Indian dental ac...
 
Impression materials / dental implant courses by Indian dental academy 
Impression materials / dental implant courses by Indian dental academy Impression materials / dental implant courses by Indian dental academy 
Impression materials / dental implant courses by Indian dental academy 
 
Impression materials
Impression materialsImpression materials
Impression materials
 

Mehr von Indian dental academy

Indian Dentist - relocate to united kingdom
Indian Dentist - relocate to united kingdomIndian Dentist - relocate to united kingdom
Indian Dentist - relocate to united kingdomIndian dental academy
 
1ST, 2ND AND 3RD ORDER BENDS IN STANDARD EDGEWISE APPLIANCE SYSTEM /Fixed ort...
1ST, 2ND AND 3RD ORDER BENDS IN STANDARD EDGEWISE APPLIANCE SYSTEM /Fixed ort...1ST, 2ND AND 3RD ORDER BENDS IN STANDARD EDGEWISE APPLIANCE SYSTEM /Fixed ort...
1ST, 2ND AND 3RD ORDER BENDS IN STANDARD EDGEWISE APPLIANCE SYSTEM /Fixed ort...Indian dental academy
 
Invisalign -invisible aligners course in india
Invisalign -invisible aligners course in india Invisalign -invisible aligners course in india
Invisalign -invisible aligners course in india Indian dental academy
 
Invisible aligners for your orthodontics pratice
Invisible aligners for your orthodontics praticeInvisible aligners for your orthodontics pratice
Invisible aligners for your orthodontics praticeIndian dental academy
 
Development of muscles of mastication / dental implant courses
Development of muscles of mastication / dental implant coursesDevelopment of muscles of mastication / dental implant courses
Development of muscles of mastication / dental implant coursesIndian dental academy
 
Corticosteriods uses in dentistry/ oral surgery courses  
Corticosteriods uses in dentistry/ oral surgery courses  Corticosteriods uses in dentistry/ oral surgery courses  
Corticosteriods uses in dentistry/ oral surgery courses  Indian dental academy
 
Cytotoxicity of silicone materials used in maxillofacial prosthesis / dental ...
Cytotoxicity of silicone materials used in maxillofacial prosthesis / dental ...Cytotoxicity of silicone materials used in maxillofacial prosthesis / dental ...
Cytotoxicity of silicone materials used in maxillofacial prosthesis / dental ...Indian dental academy
 
Diagnosis and treatment planning in completely endntulous arches/dental courses
Diagnosis and treatment planning in completely endntulous arches/dental coursesDiagnosis and treatment planning in completely endntulous arches/dental courses
Diagnosis and treatment planning in completely endntulous arches/dental coursesIndian dental academy
 
Properties of Denture base materials /rotary endodontic courses
Properties of Denture base materials /rotary endodontic coursesProperties of Denture base materials /rotary endodontic courses
Properties of Denture base materials /rotary endodontic coursesIndian dental academy
 
Use of modified tooth forms in complete denture occlusion / dental implant...
Use of modified  tooth forms  in  complete denture occlusion / dental implant...Use of modified  tooth forms  in  complete denture occlusion / dental implant...
Use of modified tooth forms in complete denture occlusion / dental implant...Indian dental academy
 
Dental luting cements / oral surgery courses  
Dental   luting cements / oral surgery courses  Dental   luting cements / oral surgery courses  
Dental luting cements / oral surgery courses  Indian dental academy
 
Dental casting alloys/ oral surgery courses  
Dental casting alloys/ oral surgery courses  Dental casting alloys/ oral surgery courses  
Dental casting alloys/ oral surgery courses  Indian dental academy
 
Dental casting investment materials/endodontic courses
Dental casting investment materials/endodontic coursesDental casting investment materials/endodontic courses
Dental casting investment materials/endodontic coursesIndian dental academy
 
Dental casting waxes/ oral surgery courses  
Dental casting waxes/ oral surgery courses  Dental casting waxes/ oral surgery courses  
Dental casting waxes/ oral surgery courses  Indian dental academy
 
Dental ceramics/prosthodontic courses
Dental ceramics/prosthodontic coursesDental ceramics/prosthodontic courses
Dental ceramics/prosthodontic coursesIndian dental academy
 
Dental implant/ oral surgery courses  
Dental implant/ oral surgery courses  Dental implant/ oral surgery courses  
Dental implant/ oral surgery courses  Indian dental academy
 
Dental perspective/cosmetic dentistry courses
Dental perspective/cosmetic dentistry coursesDental perspective/cosmetic dentistry courses
Dental perspective/cosmetic dentistry coursesIndian dental academy
 
Dental tissues and their replacements/ oral surgery courses  
Dental tissues and their replacements/ oral surgery courses  Dental tissues and their replacements/ oral surgery courses  
Dental tissues and their replacements/ oral surgery courses  Indian dental academy
 

Mehr von Indian dental academy (20)

Indian Dentist - relocate to united kingdom
Indian Dentist - relocate to united kingdomIndian Dentist - relocate to united kingdom
Indian Dentist - relocate to united kingdom
 
1ST, 2ND AND 3RD ORDER BENDS IN STANDARD EDGEWISE APPLIANCE SYSTEM /Fixed ort...
1ST, 2ND AND 3RD ORDER BENDS IN STANDARD EDGEWISE APPLIANCE SYSTEM /Fixed ort...1ST, 2ND AND 3RD ORDER BENDS IN STANDARD EDGEWISE APPLIANCE SYSTEM /Fixed ort...
1ST, 2ND AND 3RD ORDER BENDS IN STANDARD EDGEWISE APPLIANCE SYSTEM /Fixed ort...
 
Invisalign -invisible aligners course in india
Invisalign -invisible aligners course in india Invisalign -invisible aligners course in india
Invisalign -invisible aligners course in india
 
Invisible aligners for your orthodontics pratice
Invisible aligners for your orthodontics praticeInvisible aligners for your orthodontics pratice
Invisible aligners for your orthodontics pratice
 
online fixed orthodontics course
online fixed orthodontics courseonline fixed orthodontics course
online fixed orthodontics course
 
online orthodontics course
online orthodontics courseonline orthodontics course
online orthodontics course
 
Development of muscles of mastication / dental implant courses
Development of muscles of mastication / dental implant coursesDevelopment of muscles of mastication / dental implant courses
Development of muscles of mastication / dental implant courses
 
Corticosteriods uses in dentistry/ oral surgery courses  
Corticosteriods uses in dentistry/ oral surgery courses  Corticosteriods uses in dentistry/ oral surgery courses  
Corticosteriods uses in dentistry/ oral surgery courses  
 
Cytotoxicity of silicone materials used in maxillofacial prosthesis / dental ...
Cytotoxicity of silicone materials used in maxillofacial prosthesis / dental ...Cytotoxicity of silicone materials used in maxillofacial prosthesis / dental ...
Cytotoxicity of silicone materials used in maxillofacial prosthesis / dental ...
 
Diagnosis and treatment planning in completely endntulous arches/dental courses
Diagnosis and treatment planning in completely endntulous arches/dental coursesDiagnosis and treatment planning in completely endntulous arches/dental courses
Diagnosis and treatment planning in completely endntulous arches/dental courses
 
Properties of Denture base materials /rotary endodontic courses
Properties of Denture base materials /rotary endodontic coursesProperties of Denture base materials /rotary endodontic courses
Properties of Denture base materials /rotary endodontic courses
 
Use of modified tooth forms in complete denture occlusion / dental implant...
Use of modified  tooth forms  in  complete denture occlusion / dental implant...Use of modified  tooth forms  in  complete denture occlusion / dental implant...
Use of modified tooth forms in complete denture occlusion / dental implant...
 
Dental luting cements / oral surgery courses  
Dental   luting cements / oral surgery courses  Dental   luting cements / oral surgery courses  
Dental luting cements / oral surgery courses  
 
Dental casting alloys/ oral surgery courses  
Dental casting alloys/ oral surgery courses  Dental casting alloys/ oral surgery courses  
Dental casting alloys/ oral surgery courses  
 
Dental casting investment materials/endodontic courses
Dental casting investment materials/endodontic coursesDental casting investment materials/endodontic courses
Dental casting investment materials/endodontic courses
 
Dental casting waxes/ oral surgery courses  
Dental casting waxes/ oral surgery courses  Dental casting waxes/ oral surgery courses  
Dental casting waxes/ oral surgery courses  
 
Dental ceramics/prosthodontic courses
Dental ceramics/prosthodontic coursesDental ceramics/prosthodontic courses
Dental ceramics/prosthodontic courses
 
Dental implant/ oral surgery courses  
Dental implant/ oral surgery courses  Dental implant/ oral surgery courses  
Dental implant/ oral surgery courses  
 
Dental perspective/cosmetic dentistry courses
Dental perspective/cosmetic dentistry coursesDental perspective/cosmetic dentistry courses
Dental perspective/cosmetic dentistry courses
 
Dental tissues and their replacements/ oral surgery courses  
Dental tissues and their replacements/ oral surgery courses  Dental tissues and their replacements/ oral surgery courses  
Dental tissues and their replacements/ oral surgery courses  
 

Kürzlich hochgeladen

Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdf
Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdfMaximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdf
Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdfTechSoup
 
Quality Assurance_GOOD LABORATORY PRACTICE
Quality Assurance_GOOD LABORATORY PRACTICEQuality Assurance_GOOD LABORATORY PRACTICE
Quality Assurance_GOOD LABORATORY PRACTICESayali Powar
 
How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17Celine George
 
What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?TechSoup
 
How to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesHow to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesCeline George
 
CapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapitolTechU
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxDr. Asif Anas
 
In - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptxIn - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptxAditiChauhan701637
 
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptxClinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptxraviapr7
 
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfP4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfYu Kanazawa / Osaka University
 
General views of Histopathology and step
General views of Histopathology and stepGeneral views of Histopathology and step
General views of Histopathology and stepobaje godwin sunday
 
Presentation on the Basics of Writing. Writing a Paragraph
Presentation on the Basics of Writing. Writing a ParagraphPresentation on the Basics of Writing. Writing a Paragraph
Presentation on the Basics of Writing. Writing a ParagraphNetziValdelomar1
 
UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024UKCGE
 
Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...raviapr7
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsEugene Lysak
 
Prescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxPrescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxraviapr7
 
Philosophy of Education and Educational Philosophy
Philosophy of Education  and Educational PhilosophyPhilosophy of Education  and Educational Philosophy
Philosophy of Education and Educational PhilosophyShuvankar Madhu
 
CAULIFLOWER BREEDING 1 Parmar pptx
CAULIFLOWER BREEDING 1 Parmar pptxCAULIFLOWER BREEDING 1 Parmar pptx
CAULIFLOWER BREEDING 1 Parmar pptxSaurabhParmar42
 
Easter in the USA presentation by Chloe.
Easter in the USA presentation by Chloe.Easter in the USA presentation by Chloe.
Easter in the USA presentation by Chloe.EnglishCEIPdeSigeiro
 

Kürzlich hochgeladen (20)

Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdf
Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdfMaximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdf
Maximizing Impact_ Nonprofit Website Planning, Budgeting, and Design.pdf
 
Quality Assurance_GOOD LABORATORY PRACTICE
Quality Assurance_GOOD LABORATORY PRACTICEQuality Assurance_GOOD LABORATORY PRACTICE
Quality Assurance_GOOD LABORATORY PRACTICE
 
Finals of Kant get Marx 2.0 : a general politics quiz
Finals of Kant get Marx 2.0 : a general politics quizFinals of Kant get Marx 2.0 : a general politics quiz
Finals of Kant get Marx 2.0 : a general politics quiz
 
How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17How to Add Existing Field in One2Many Tree View in Odoo 17
How to Add Existing Field in One2Many Tree View in Odoo 17
 
What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?What is the Future of QuickBooks DeskTop?
What is the Future of QuickBooks DeskTop?
 
How to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 SalesHow to Manage Cross-Selling in Odoo 17 Sales
How to Manage Cross-Selling in Odoo 17 Sales
 
CapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptxCapTechU Doctoral Presentation -March 2024 slides.pptx
CapTechU Doctoral Presentation -March 2024 slides.pptx
 
Ultra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptxUltra structure and life cycle of Plasmodium.pptx
Ultra structure and life cycle of Plasmodium.pptx
 
In - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptxIn - Vivo and In - Vitro Correlation.pptx
In - Vivo and In - Vitro Correlation.pptx
 
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptxClinical Pharmacy  Introduction to Clinical Pharmacy, Concept of clinical pptx
Clinical Pharmacy Introduction to Clinical Pharmacy, Concept of clinical pptx
 
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdfP4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
P4C x ELT = P4ELT: Its Theoretical Background (Kanazawa, 2024 March).pdf
 
General views of Histopathology and step
General views of Histopathology and stepGeneral views of Histopathology and step
General views of Histopathology and step
 
Presentation on the Basics of Writing. Writing a Paragraph
Presentation on the Basics of Writing. Writing a ParagraphPresentation on the Basics of Writing. Writing a Paragraph
Presentation on the Basics of Writing. Writing a Paragraph
 
UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024UKCGE Parental Leave Discussion March 2024
UKCGE Parental Leave Discussion March 2024
 
Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...Patient Counselling. Definition of patient counseling; steps involved in pati...
Patient Counselling. Definition of patient counseling; steps involved in pati...
 
The Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George WellsThe Stolen Bacillus by Herbert George Wells
The Stolen Bacillus by Herbert George Wells
 
Prescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptxPrescribed medication order and communication skills.pptx
Prescribed medication order and communication skills.pptx
 
Philosophy of Education and Educational Philosophy
Philosophy of Education  and Educational PhilosophyPhilosophy of Education  and Educational Philosophy
Philosophy of Education and Educational Philosophy
 
CAULIFLOWER BREEDING 1 Parmar pptx
CAULIFLOWER BREEDING 1 Parmar pptxCAULIFLOWER BREEDING 1 Parmar pptx
CAULIFLOWER BREEDING 1 Parmar pptx
 
Easter in the USA presentation by Chloe.
Easter in the USA presentation by Chloe.Easter in the USA presentation by Chloe.
Easter in the USA presentation by Chloe.
 

Impressions for fpd / implant dentistry course

  • 1. IMPRESSIONS IN FIXED PARTIAL DENTURESINDIAN DENTAL ACADEMY Leader in continuing dental education www.indiandentalacademy.com www.indiandentalacademy.com
  • 4.  Well-fitting indirect restorations can only be made if there are accurate casts of the oral tissues available, made from high quality impressions.  A good quality impression is only obtained when we have a thorough knowledge of materials, their properties, and techniques for their best manipulation. www.indiandentalacademy.com
  • 6. IMPRESSION : A negative likeliness or copy in reverse of the surface of an object; an imprint of the teeth and adjacent structures for use in dentistry – G.P.T-8 IMPRESSION TRAY : A receptacle into which suitable impression material is placed to make a negative likeliness (or) a device that is used to carry, confine, and control impression material while making impression– G.P.T-8 www.indiandentalacademy.com
  • 7. IMPRESSION MATERIAL: Any substance or combination of substances used for making an impression or negative reproduction. – G.P.T- 8 IMPRESSION TECHNIQUE : A method and manner used in making a negative likeness. – G.P.T-8 www.indiandentalacademy.com
  • 8. HistoryHistory  Philip Pfaff-1756  First described taking impression with softened wax  Christopher Francois Delabarre-1820  Introduced the metal impression tray  Chapin Haris-1853  First used Plaster of Paris for making impressions  Charles Stent-1857  Introduced the first impression compound www.indiandentalacademy.com
  • 9.  Sears-1937  First used agar hydrocolloids for recording crown impressions.  United States-1945  Introduced alginate during World War II.  SL Pearson-1955  Developed synthetic rubber base impression materials  Polysulfide- Late 1950’S  First developed as an industrial sealant. www.indiandentalacademy.com
  • 10.  Condensation Silicone- Early 1960’s  Addition Silicone-1970’s  Polyether- Late 1970’s  Polyether Urethane Dimethacrylate - Late 1980’s www.indiandentalacademy.com
  • 11. Properties Of An Ideal Impression 1)Complete plasticity before cure 2)Sufficient fluidity to record fine detail. 3)The ability to wet the oral tissues. 4) Dimensional accuracy. 5)Dimensional stability. 6)Complete elasticity after cure. 7)Optimal stiffness. www.indiandentalacademy.com
  • 12. Impression Materials Used In F.P.D 1)Hydrocolloid impression material a) Reversible hydrocolloid b) Irreversible hydrocolloid 2)Elastomeric impression materials a) Polysulfide b)Addition silicone c) Condensation silicone d)Polyether www.indiandentalacademy.com
  • 13. AGAR (reversible hydrocolloid) History  In 1925, Alphous Poller of Vienna was granted a British patent for a totally different type of impression material called as Negacol  Later Poller's 'Negacoll’ was modified and introduced to the dental profession as 'Dentacol’ in 1928. www.indiandentalacademy.com
  • 14. Example  Slate Hydrocolloid (Van R)  Cohere  Superbody  Super syringe www.indiandentalacademy.com
  • 15.  Available as - syringe and tray material Composition: Component Function Composition Agar Brush – heap structure 13 – 17% Borax Strength 0.2 – 0.5% Potassium Sulfate Gypsum hardener 1.0 – 2.0% Water Reaction 80% Alkyl Benzoate Prevent growth of mold in impression material during storage. 0.1% Color and Flavors Taste & appearance Trace www.indiandentalacademy.com
  • 16.  Setting reaction: Agar hydrocolloid (hot) Agar hydrocolloid (cold) (Sol) (Gel) Cool to 43 C Heat to 100 C Manipulation: Three chamber conditioning unit (1) Liquefy at 100 0 C for 10 minutes converts gel to sol (2) Store at 65 – 68 0 C place in tray (3) Temper at 46 0 C for 3 minutes seat tray (4) cool with water at 20 0 C for 3 minutes converts sol to gel www.indiandentalacademy.com
  • 17. Advantages  Accurate reproduction of surface detail  Hydrophilic  displace moisture, blood, fluids  Inexpensive  No custom tray or adhesives  No mixing required www.indiandentalacademy.com
  • 18. Disadvantages  Initial expense  special equipment  Material should be prepared in advance  Tears easily  Dimensionally unstable  Pour immediately  Single cast  Difficult to disinfect www.indiandentalacademy.com
  • 19. ALGINATE (irreversible hydrocolloid)  Alginate was developed as a substitute for agar when the agar impression material became scarce because of World war II (Japan was a prime source of agar). Examples  Zelgan, jeltrate (Dentsply)  Coe Alginate (GC America)  Integra(kerr) www.indiandentalacademy.com
  • 20. Composition Component Function Weight percentage Na / Potassium alginate Soluble alginate 15 Calcium sulfate dihydrate Reactor 16 Potassium titanium Fluoride Accelerator 3 Zinc oxide Filler particles 4 Diatomaceous earth Filler particles 60 Sodium phosphate Retarder 2 www.indiandentalacademy.com
  • 21. Setting reaction: (gelation process) 2 Na3PO4 + 3 CaSO4 Ca3(PO4)2 + 3 Na2SO4 Na alginate + CaSO4 Ca alginate + Na2SO4 (powder) (gel) H2O www.indiandentalacademy.com
  • 22. Modified alginates  Alginates modified by the incorporation of silicone polymers (paste form)  Dustless alginate - glycerin incorporated to agglomerate the particles.  Making the powder denser so that no dust is formed when the lid is opened after tumbling. www.indiandentalacademy.com
  • 23. NEWER ALGINATES  Kromopan 100. manufactured by LASCOD  MILLENIUM ALGIN is considered an alginate of new generation alginate.  The impression can be stored for many hours in a Long Life Bag before casting the model without undergoing any change for over 100 hours www.indiandentalacademy.com
  • 24. AUTOMIX DISPENSING: (Alginate from Kerr international)  No hand mixing. Eliminates mess and cleanup. Saves time and material.  Delivery options. Cartridge or Volume™ auto mix dispensing.  Impressions remain stable. You can pour immediately or when it’s convenient. Impressions retain dimensional stability for months. www.indiandentalacademy.com
  • 27. Advantages:  Inexpensive  Easy to use  Hydrophilic  displace moisture, blood, fluids  Stock trays www.indiandentalacademy.com
  • 28. Disadvantages:  Tears easily  Dimensionally unstable  immediate pour  single cast  Lower detail reproduction  unacceptable for working cast of fixed prosthodontics  High permanent deformation  Difficult to disinfect www.indiandentalacademy.com
  • 29. NON AQUEOUS ELASTOMERIC IMPRESSION MATERIALS  These are Synthetic rubbers.  These mimic natural rubber (scarce during World War II)  Initially called rubber impression materials  Currently referred as elastomers or elastomeric impression materials. www.indiandentalacademy.com
  • 31. Polysulfide  The first elastomer used for dental impressions Examples  Permlastic (Kerr)  Omni-Flex (GC America) – copper hydroxide system  Coe-flex( GC America) www.indiandentalacademy.com
  • 32.  Available in 3 viscosities,  light body and medium body ,heavy body. www.indiandentalacademy.com
  • 33. Manipulation  With the proper lengths of the two pastes squeezed onto a mixing pad or glass slab, the catalyst paste is first collected on a stainless steel spatula and then distributed over the base, and the mixture is spread out over the mixing pad.  The mass is then scraped up with the spatula blade and again smoothed out. www.indiandentalacademy.com
  • 34.  If sufficient force is applied and spatulation is performed rapidly, the material will seem thinner and easier to handle. This phenomenon is known as pseudoplasticity.  Most accurate impressions are made using custom acrylic trays because of uniform thickness of the material. www.indiandentalacademy.com
  • 35. Advantages Disadvantages  Long working time  High tear resistant  inexpensive to use  Long shelf life Requires a custom tray Must be poured in stone immediately Potential for significant distortion Odor offends patients Messy and stains clothes Second pour is less accurate www.indiandentalacademy.com
  • 37. CONDENSATION SILICONE  Condensation reaction – a polymerization reaction in which the polymer chains grow simultaneously and a reaction byproduct is ethanol Available In Three Viscosities:  Light body  Medium body  Putty body Supplied as:  Paste – two pastes in collapsible tubes  Putty – jars www.indiandentalacademy.com
  • 38. Examples:  Speedex (Coltene/Whaledent)  Primasil (TISS Dental)  Accoe (GC-Amer)  Xantopren (Unitek)  Elasticon (Kerr) www.indiandentalacademy.com
  • 39. Composition: Composition Components Function Base paste Hydroxyl terminated polydimethyl siloxane prepolymer undergoes cross linking to form rubber Silica Filler Reactor Orthoethyl Silicate Cross linking agent Stannous octate Catalyst www.indiandentalacademy.com
  • 40. Advantages:  Better elastic properties  Clean, pleasant  Stock tray  Good working and setting time Disadvantages: Permanent deformation – high – 1-3% Poor dimensional stability high shrinkage  Hydrophobic www.indiandentalacademy.com
  • 41. ADDITION SILICONES  Frequently called polyvinylsiloxane or vinyl polysiloxane impression materials. Supplied in 4 viscosities  Light body  Medium body  Heavy body  Putty www.indiandentalacademy.com
  • 42. Examples:  Extrude (Kerr)  Express (3M/ESPE)  Aquasil (Dentsply )  Virtual (Ivoclar Vivadent) www.indiandentalacademy.com
  • 43. Composition: Components Function Base paste Hydroxyl terminated polymethyl siloxane prepolymer Undergoes cross linking to form rubber Colloidal silica Filler Reactor Polyvinyl silicone prepolymer Colloidal silica Filler Chloroplatinic acid Catalyst www.indiandentalacademy.com
  • 44. Advantages:  Excellent reproduction of surface details  Highly accurate  High dimensional stability  pour up to one week  Stock or custom trays  Multiple casts  Easy to mix  Pleasant odor Disadvantages:  Expensive  Short working time  Lower tear strength  Possible hydrogen gas release www.indiandentalacademy.com
  • 45. POLYETHER  Introduced in Germany in late 1960s. Available as  Base and accelerator in collapsible tubes.  The accelerator tube is usually smaller.  Earlier supplied in single viscosity.  A third tube containing a thinner was provided. Available in 3 viscosities  Light body  Medium body  Heavy body www.indiandentalacademy.com
  • 46. Examples  Impregum F (3M/ESPE)  Permadyne (3M/ESPE)  Pentamix (3M/ESPE)  P2 (Heraeus Kulzer)  Polygel (Dentsply ) www.indiandentalacademy.com
  • 48. Advantages  Highly accurate  Good dimensional stability  hydrophilic  Good surface detail  Pour within one week  Multiple casts  Good wettability  Good shelf life Disadvantages Expensive Short working time Rigid difficult to remove from undercuts Bitter taste Low tear strength Absorbs water - changes dimension - Leaches components www.indiandentalacademy.com
  • 49. Impression Techniques  1. Stock tray technique/putty wash technique - Double mix - Single mix  2. Custom tray technique - Single mix - Double mix  3. Closed bite double arch technique  4. Copper band technique  5. Reversible hydrocolloid technique www.indiandentalacademy.com
  • 50. STOCK TRAY IMPRESSION TECHNIQUE (Putty wash technique): Mixing method: Double mix and single mix Procedure :  Place patient in supine position.  Select tray type based on relative need for retention and personal preference.  Select tray shape and size based on patients arch shape and size. www.indiandentalacademy.com
  • 51.  Coat the tray with adhesive on the inside and rim.  Mix the high viscosity putty impression material according to manufacturer’s instructions.  Roll putty into elongated cylinder.  Insert into the stock impression tray. www.indiandentalacademy.com
  • 52.  Cover putty with the manufacturer’s spacer (a sheet of polyethylene)  Insert and seat the tray with a rocking motion.  Hold and wait until initial set.  Remove from the mouth with minimal sideward movement.  Wait and test for final set with the clinical final set, which is when a finer nail impression rebounds completely.  Peel off the spacer.  Remove excess impression material with a sharp knife. www.indiandentalacademy.com
  • 53. MAKING FINAL IMPRESSION:  Choose a large mixing pad approximately six by eight inches.  Choose a spatula that is long enough to pick up the mixed impression material, yet sufficiently pliable to mix the material against the pad. www.indiandentalacademy.com
  • 54.  Mix the low-viscosity, impression material according to manufacturer’s instructions.  First use a circular motion, joining the two strands. Then a figure eight motion to blend and flatten the mixture onto the mixing pad.  While flattening the mixture, limit the number of times of lifting the spatula from the pad, this reduces the number of voids in the mixture. www.indiandentalacademy.com
  • 55.  Load the low viscosity impression material on to a syringe .  Syringe in the inaccessible area first eg disto lingual line angle.  Seat the tray .  Wait for the final set.  Remove the tray parallel to the preparation path of withdrawal.  The impression is evaluated for the finish lines and for any distortion and tear. www.indiandentalacademy.com
  • 56. SINGLE MIX TECHNIQUE:  For the stock tray Single mix insert the low viscosity impression material into the prepared area  Putty material is loaded into the stock tray  Position the tray over the arch.  Seat from posterior to anterior, allowing the excess to extrude anteriorly.  Apply force in a vertical direction until further seating is impossible.  Evaluate final position and adjust tray quickly if necessary. www.indiandentalacademy.com
  • 57. EVALUATING FINAL IMPRESSION  Elastomeric material should be present 0.5 mm beyond visible finish line.  Note presence of bur marks, the junction of smooth root surface, and continuous finish line.  There should be no shiny smooth areas; if present, they suggest moisture contamination.  There should be no tray show- though in any areas of the impression except at tissue stops. www.indiandentalacademy.com
  • 58.  There must be no voids present, they suggest mixing problems or contamination.  There should be no thin areas leaving the finish line unsupported. These areas distort under the weight of the stone. www.indiandentalacademy.com
  • 59. Custom Tray Fabrication For Elastomeric Impression 1)Mark the border of the tray on the diagnostic cast with a pencil approximately 5mm apically to crest of the free gingiva. www.indiandentalacademy.com
  • 60. 2)Adapt a wax spacer to the diagnostic cast two layers for 2.5mm thickness approximately. www.indiandentalacademy.com
  • 62. 3)Apply a layer of tinfoil over the wax. 4)Mix autopolymerizing acrylic resin according to manufacturers recommendation 5)Adapt the resin to the cast when in dough stage. www.indiandentalacademy.com
  • 63. Tray handle is made Borders are trimmed and the tray is polished www.indiandentalacademy.com
  • 64. Lateral wings can be made which will help in easy removal of the tray www.indiandentalacademy.com
  • 65. Prepare syringe:  Lubricate the syringe lightly.  Measure arch length of tray to guide in dispensing the amount of elastomer. (Dispense one time the length of the tray for the low viscosity elastomer). www.indiandentalacademy.com
  • 66. Making the final impression. Medium or high viscosity is used in the tray and low viscosity in the syringe. The low viscosity material syringed in the prepared site. The high viscosity material is placed in the custom tray and seated in the mouth. www.indiandentalacademy.com
  • 67. The impression is removed and evaluated. www.indiandentalacademy.com
  • 68. Close Bite Double Arch Method synonyms :dual quad tray, double arch , triple arch , accu -bite ,closed mouth impression. Requirements The articulator should provide for a positive stop or there should be sufficient teeth to maintain the vertical dimension. There should be sufficient space distal to the terminal tooth in the arch to allow tray approximation. www.indiandentalacademy.com
  • 69. Advantages maximum intercuspation position is captured. Less impression material is needed. Less gagging may occur. Disadvantages The tray is not rigid . Limited to one casting per quadrant . The distribution of impression material is not uniform www.indiandentalacademy.com
  • 70. Technique Evaluate the fit of the tray in the patients mouth. Observe the complete bilateral closure and the patients comfort. Practice till the patient is familiar with the task. www.indiandentalacademy.com
  • 71. Making the final impression  Mix the low viscosity material and load the syringe  The high viscosity material is used in the tray.  After the low viscosity material is syringed the tray is positioned on the arch.  Instruct the patient to close the mouth and observe for the interdigitation on the opposite arch.  Wait for the material to set . www.indiandentalacademy.com
  • 72. Instruct the patient to open the mouth remove the tray by applying equal pressure bilaterally. Evaluate the impression. www.indiandentalacademy.com
  • 73. Copper Band or Tube Method The copper band is used to salvage an impression of multiple preparation where there is only vague margins on one or two preparation that are not adequately replicated in the impression. Fitting of the copper band to preparation A copper band is selected and annealed by heating on a flame and quenching in alcohol. Mark the finish line with the explorer and round off the edges. evaluate the fit and cut orientation hole on facial surface . www.indiandentalacademy.com
  • 74. Copper band with orientation holes www.indiandentalacademy.com
  • 76. Evaluating the fit of the copper band The circumference of the copper band must be such that it will fit over the preparation and still project into the gingival crevice. An oversize band should not be used since it will impinge on the gingival tissues. www.indiandentalacademy.com
  • 77. Making the compound plug The green stick compound is heated over the Bunsen flame . Insert the warm compound mass to fill approximately the top third of the copper band. Seat and orient on to preparation and compress excess in to the band. The compound should just touch the occlusal surface . Remove and evaluate the impression, only the occlusal surface should be impressed. Remove 0.2mm of the compound to create space for the heavy body poly vinyl silicone. Drill a hole through the centre of the compound plug. www.indiandentalacademy.com
  • 78. Making the impression. Coat the internal surface sparingly with adhesive . Clean and isolate the preparation. Mix heavy viscosity material and inject in to the band and position it on the tooth. Wait for the material to set remove the band and inspect the impression www.indiandentalacademy.com
  • 79. Copper band with the final impression www.indiandentalacademy.com
  • 80. Reversible hydrocolloid technique This impression technique requires a special conditioning unit which consists of 3 thermostatically controlled water baths. 1. A liquefaction bath . 2.A storage bath . 3.A tempering bath. www.indiandentalacademy.com
  • 81. Rimlock trays with stops www.indiandentalacademy.com
  • 82. Procedure Select the correct size of water cooled impression trays. Place small modeling compound or prefabricated stops in the tray to prevent over seating . Fill the impression tray with heavy bodied material from the storage bath and place it in the tempering bath Load the syringe material in the syringe and replace it in the storage bath. Carefully remove the retraction cord and flood the tooth with water. www.indiandentalacademy.com
  • 83. Inject the syringe material on the tooth cover the entire tooth. Remove the impression tray from the bath wipe with the gauze and place it in the mouth. After seating cold water is circulated through the tray until the impression material is set. Remove the impression with a rapid motion, wash with cold water ,evaluate for accuracy. www.indiandentalacademy.com
  • 84. Final impression in reversible hydrocolloid www.indiandentalacademy.com
  • 85. Laminate Technique (or) Agar Alginate Combination Technique  After injecting the syringe agar on to the area to be recorded, an impression tray containing a mix of chilled alginate that will bond with the syringe agar is positioned on it.  The alginate gels by a chemical reaction, whereas the agar gels by means of contact with the cool alginate rather than the water circulating through the tray. www.indiandentalacademy.com
  • 86. Advantages 1. Less air bubbles 2. Water cooled trays are not required 3. It sets faster than the regular agar technique. www.indiandentalacademy.com
  • 87. Wet Field Technique  This is relatively new technique which has become popular.the areas to be recorded are actually flooded with warm water.  Then the syringe material is introduced quickly, liberally and in bulk to cover the occlusal and/or incisal areas only.  while the syringe material is still liquid, the tray material is seated. www.indiandentalacademy.com
  • 88.  The hydraulic pressure of the viscous tray materials forces the fluid syringe hydrocolloid down into the areas to be recorded.  This motion displaces the syringe materials as well as blood and debris throughout the sulcus www.indiandentalacademy.com
  • 89. The matrix impression system Gus J. Livaditis jpd 1998, vol 79,issue 2  The system uses a custom matrix to control the sulcular environment and to deliver the impression material subgingivally . It also incorporates the attributes of traditional impression methods and overcomes partial the deficiencies of impression making such as registration of the subgingival Margins, gingival retraction and relapse, hemostasis and sulcular cleaning, strengthening the sulcular flange of impression and simplification for making complex impressions. www.indiandentalacademy.com
  • 90. The system uses three impression materials  1.A suitable elastomeric semi rigid material to form the matrix.  2. A high viscosity elastomeric impression material which will preferably bond to the matrix forming material, required to make an impression of the preparation of the matrix  3. A stock tray with medium viscosity elastomeric impression material to pick up the matrix impression and remaining arch not covered by the matrix.  Carrier for matrix forming material, it may be either custom made or stock available. www.indiandentalacademy.com
  • 91. Clear plastic carrier selected from assortment of premade forms. Matrix is made in carrier with polyvinyl siloxane material before soft tissue is retracted. Immediately after tooth preparation and before any retraction procedures www.indiandentalacademy.com
  • 92.  Black Lines Indicate Sulcular extension. Thick red line indicates crest of gingiva. Two black marks point out proximal contacts that must be relieved. Slender bur or knife edged rubber wheel used to enlarge interproximal embrasures. Matrix should extend one half to two thirds of tooth beyond prepared teeth and close to gingival crest. www.indiandentalacademy.com
  • 93. syringe is used to fill matrix with high viscosity impression material. Matrix impression is seated with light pressure. Stock tray filled with medium viscosity impression material is seated over matrix impression before matrix material polymerizes. www.indiandentalacademy.com
  • 94. REVIEW OF LITERATURE  Nachum Samet DMD, Michael Shohat DMD, Alon Livny DMD and Ervin I. Weiss DMD: A clinical evaluation of fixed partial denture impressions; J Prosthet Dent, volume 94, issue 2, August 2005, pages 112 – 117: This study evaluated the quality of impressions sent to commercial laboratories for the fabrication of fixed partial dentures (FPD) by describing the frequency of clinically detectable errors and by analyzing correlations between the various factors involved. Within the limitations of this study, impressions made with polyethers had the most detectable errors, followed by condensation-type silicones. The high frequency of detectable errors found in impressions sent for FPD fabrication is of concern. www.indiandentalacademy.com
  • 95.  Hung SH, Purk JH, Tira DE, Eick JD : Accuracy of one-step versus two-step putty wash addition silicone impression technique; J Prosthet Dent 1992 May; 67(5):583-9: This study compared the accuracy of one-step putty wash with two-step putty wash impression techniques. Five addition silicone impression materials-Mirror 3 (MR), Mirror 3 Extrude (ME), Express (E), Permagum (P), and Absolute (A)-- were tested. A stainless steel model containing two full-crown abutment preparations was used as the positive control. Five replications for one-step and two-step putty wash impressions of the master model were made for each test material. Accuracy of the materials was assessed by measuring six dimensions on stone dies poured from impressions of the master model. Accuracy of addition silicone impression material is affected more by material than technique. Accuracy of the putty wash one-step impression technique was not different from the putty wash two-step impression technique except at one of the six dimensions where one-step was more accurate than two-step. Mirror 3 putty wash two-step impression presented less distortion than Mirror 3 Extrude putty wash one-step or two-step impression. www.indiandentalacademy.com
  • 96.  Nissan J, Laufer BZ, Brosh T, Assif D : Accuracy of three polyvinyl siloxane putty-wash impression techniques; J Prosthet Dent. 2000 Feb; 83(2):161-5; This study assessed the accuracy of 3 putty-wash impression techniques (1) 1-step (putty and wash impression materials used simultaneously); (2) 2-step with 2-mm relief (putty first as a preliminary impression to create 2-mm wash space with prefabricated copings. In the second step, the wash stage was carried out); and (3) 2-step technique with a polyethylene spacer (plastic spacer used with the putty impression first and then the wash stage). using the same impression material (polyvinyl siloxane) in a laboratory model. For each technique, 15 impressions were made of a stainless steel master model that contained 3 complete crown abutment preparations, which were used as the positive control. Accuracy was assessed by measuring 6 dimensions on stone dies poured from impressions of the master model. CONCLUSION: The polyvinyl siloxane 2-step, 2-mm, relief putty-wash impression technique was the most accurate for fabricating stone dies. www.indiandentalacademy.com
  • 97. SUMMARY A good impression is an exact replica of each prepared tooth and should include adequate amount of the unprepared surfaces adjacent to the margin. Impression technique and material should be selected on the basis of biologic factor dictated by the anatomy and the physiology of the mouth dictated by the orofacial tissues. Even though there are innumerable techniques and procedure for impression making ,it is the responsibility of the dentist to select the best possible procedure based on sound knowledge , for achieving the best possible result for the patient. www.indiandentalacademy.com
  • 98. REFERENCES  1.Phillips science of dental materials – 11th edition – Anusavice  2.fundamentals of fixed prosthdontics- 3rd edition Herbert T.Shillingburg  3.Dental Materials – E. C. Coombe  4.Applied Dental Materials – 8th Edition – McCabe  5.Contemporary Fixed Prosthodontics – 3rd edition Stephen F.Rosenstiel www.indiandentalacademy.com
  • 99. 1.Nachum Samet DMD, Michal Shohat DMD, Alon Livny DMD and Ervin I. Weiss DMD: A clinical evaluation of fixed partial denture impressions; J Prosthet Dent, volume 94, issue 2, August 2005, pages 112 – 117. 2.Hung SH, Purk JH, Tira DE, Eick JD : Accuracy of one-step versus two-step putty wash addition silicone impression technique; J Prosthet Dent. 1992 May; 67(5):583-9. 3. Laufer BZ, Brosh T, Assif D : Accuracy of three polyvinyl siloxane putty-wash impression techniques; J Prosthet Dent. 2000 Feb; 83(2):161 www.indiandentalacademy.com
  • 100. Thank youFor more details please visit www.indiandentalacademy.com www.indiandentalacademy.com

Hinweis der Redaktion

  1. To obtain an impression is the first step in indirect fabrication of a prosthesis.. And fixed prosthodontics is practised as indirect restorations
  2. Plasticity-ability to be shaped
  3. Agar-organic hydrophilic colloid(polysaccharide) extracted from certain sea weeds.
  4. Potassium titanium fluoride –accelerator for setting of gypsum
  5. W/P ratio is specified by the manufacturer. Mixing is done in a clean bolw with a wide bladed spatula.. The mixing is started in circular to wet the powder with water and later spatulation is done by swiping it against the side of the bowl. A figure of 8 motion can be used.
  6. They were introduced in 1950 s . They were acceptable due to dimensional stability and tear resistance when compared to hydrocolloid impression mateials.
  7. There is a slight contraction in these materials during polymerisation but this can be compensated by custom trays since bulk is reduced The main component is multifunctional mecaptan or polysulfide polymer. Plasticizer to get appropriate viscosity of paste.sulphur to accelerate the reaction
  8. Why catalyst is mixed over the base.
  9. Polydimethy siloxane reacts with tetraethyl orthosilicate in presence of stannous octoate to give ethyl alcohol
  10. Base paste contains amine terminated polyether polymer with is cross linked with aromatic sulfonate ester
  11. Autoplymerised,thermoplastic and photopolymerised resin
  12. Black lines indicate sulcular extension and proximal contacts .
  13. Nachum etal did a study to evaluate the fpd impressions
  14. Hung etal did a study to evaluate the accuracy of one step vs two step putty wash impression techniques