Polyether Final Dental Impressions

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Polyether ImpressionPolyether Impression

ParagParag R. R. KachaliaKachalia, DDS, DDSJessie V. Vallee, DDSJessie V. Vallee, DDS

Elastic Impression MaterialsElastic Impression MaterialsReviewReview

•• Reversable HydrocolloidsReversable Hydrocolloids

HydrophyllicHydrophyllic

Must be poured immediately but can only beMust be poured immediately but can only bepoured once. They lack dimensional stability poured once. They lack dimensional stability due to due to syneresis syneresis ( the ease in which water can be ( the ease in which water can be released and released and imbibition imbibition ( the rate that water can be( the rate that water can beabsorbed).absorbed).

Excellent dimensional accuracy.Excellent dimensional accuracy.

Requires additional equipment to use and special impressiRequires additional equipment to use and special impression trayson trays


•• Polysulfide polymer, commonly referred to as rubber Polysulfide polymer, commonly referred to as rubber base.base.

High tear strengthHigh tear strength

Messy, unpleasant odor, long setting time (10 minutes)Messy, unpleasant odor, long setting time (10 minutes)

Poor dimensional stability, should be poured as soon as Poor dimensional stability, should be poured as soon as possible.possible.


•• Condensation siliconesCondensation silicones

Pleasant to use, short setting time.Pleasant to use, short setting time.

Hydrophobic, stability is only fair due to Hydrophobic, stability is only fair due to dimensional change with time.dimensional change with time.

Should be poured immediately.Should be poured immediately.


•• Addition Silicone (Aquasil)Addition Silicone (Aquasil)

Excellent dimensional stability, pleasant to use, short Excellent dimensional stability, pleasant to use, short setting time, setting time, automixautomix is available.is available.

Hydrophobic, some have surfactants added to Hydrophobic, some have surfactants added to empartempart a hydrophilic characteristic. Can imbibe a hydrophilic characteristic. Can imbibe moisture.moisture.

Some release hydrogen gas after setting, requiring a Some release hydrogen gas after setting, requiring a delay in pouringdelay in pouring


•• Polyether (Polyether (ImpregumImpregum))

Excellent dimensional stability, very accurate, short settinExcellent dimensional stability, very accurate, short setting time, g time, automixautomix and auto dispensing systems available.and auto dispensing systems available.

The set material can be very stiff, new formulations offer sThe set material can be very stiff, new formulations offer softer ofter set material. Care must be taken with the stiffer set materialsset material. Care must be taken with the stiffer set materials not not to break teeth when separating casts form the impression.to break teeth when separating casts form the impression.

Will imbibe moisture if stored in a moist environment.Will imbibe moisture if stored in a moist environment.

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MonophaseMonophase Wash Wash TechniqueTechnique

Polyether (ImpregumPolyether (Impregum--3M ESPE)3M ESPE)

Polyether (ImpregumPolyether (Impregum--3M ESPE)3M ESPE) Polyether (ImpregumPolyether (Impregum--3M ESPE)3M ESPE)

Polyether (ImpregumPolyether (Impregum--3M ESPE3M ESPE Polyether (ImpregumPolyether (Impregum--3M ESPE3M ESPE

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Polyether (ImpregumPolyether (Impregum--3M ESPE3M ESPE



Volume indicator windowOn Pentamix machine

Volume indicator on Pentamix machine

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Polyether (ImpregumPolyether (Impregum--3M 3M ESPEThESPETh

•• This technique is essentially the same as the one used for the This technique is essentially the same as the one used for the Aquasil impressionAquasil impression

•• Load the tray with Load the tray with monophasemonophase Material from the Pentamix Material from the Pentamix machine.machine.

•• Load the impression syringe with the wash material.Load the impression syringe with the wash material.•• Either place the extra wash material on the occlusal surfaces ofEither place the extra wash material on the occlusal surfaces of

the remaining teeth in the arch or place some wash material on the remaining teeth in the arch or place some wash material on the top of the the top of the monophasemonophase material in the tray.material in the tray.

•• Syringe the wash material around the preparation, watch the Syringe the wash material around the preparation, watch the material completely cover the margin and completely cover the material completely cover the margin and completely cover the preparation.preparation.

•• Seat the tray and leave supported but undisturbed until the Seat the tray and leave supported but undisturbed until the Impragum has completely set, approx. 5 minutes. Impragum has completely set, approx. 5 minutes.

Custom Tray Wash Custom Tray Wash TechniqueTechnique

(Wash (Wash –– Wash technique)Wash technique)


•• Custom tray must be perforatedCustom tray must be perforated

•• Custom tray must have the polyether adhesive Custom tray must have the polyether adhesive applied to all internal surfacesapplied to all internal surfaces

•• Must only use wash material in custom tray. Must only use wash material in custom tray. Never use Never use monophasemonophase with light body wash in with light body wash in custom tray.custom tray.



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•• Load custom tray with Load custom tray with ImpregumImpregum wash materialwash material•• Load Impression syringe with Load Impression syringe with ImpregumImpregum wash materialwash material•• Inject wash material into Inject wash material into sulcussulcus around the around the

circumference of preparation, do not remove tip of circumference of preparation, do not remove tip of syringe from the mass of material until entire syringe from the mass of material until entire preparation has been covered.preparation has been covered.

•• Seat the custom tray. Let tray remain undisturbed until Seat the custom tray. Let tray remain undisturbed until ImpregumImpregum has completely set, approximately 5 minutes has completely set, approximately 5 minutes after the tray was seated.after the tray was seated.

TodayToday’’s Lab Assignments Lab Assignment

•• Refine preparation for tooth #20Refine preparation for tooth #20•• Fabricate a provisional restoration using Fabricate a provisional restoration using

Integrity.Integrity.•• No lecture this afternoonNo lecture this afternoon•• Afternoon LabAfternoon Lab

Make Make ImpregumImpregum impression #20 using custom impression #20 using custom tray. We must get an acceptable impression by tray. We must get an acceptable impression by the end of todaythe end of today’’s laboratory session.s laboratory session.

TodayToday’’s projectss projects

•• Refine FVC prep tooth # 20Refine FVC prep tooth # 20•• Fabricate a provisionalFabricate a provisional

–– Ideal provisional to be graded by 12:45 P.M.Ideal provisional to be graded by 12:45 P.M.

•• Take a final impression on tooth #20 utilizing Take a final impression on tooth #20 utilizing ImpregumImpregum impression material in a custom trayimpression material in a custom tray

•• Impression should be completed by 4:00Impression should be completed by 4:00•• Practice a new #20 for the practical next week.Practice a new #20 for the practical next week.

Due Next WeekDue Next Week

•• #20 FVC preparation#20 FVC preparation–– Please put this tooth into a second Please put this tooth into a second typodonttypodont for your for your

instructors to grade during your practicalinstructors to grade during your practical

•• #20 provisional#20 provisional•• Both projects should be available for grading at Both projects should be available for grading at

8:00 A.M. on 11/19/20088:00 A.M. on 11/19/2008

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Practical ProtocolPractical Protocol

Polyether Final Dental Impressions

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