Impressions1

Complete Dentures

Appointment 2

Final Impressions

Introduction•Trays•Border molding•Making Impression•Post-Dam

Baseplates

Trim master cast

Draw outline 2 mmshort of periphery.

Block out undercutswith wax or putty.

Border of Mandibular Custom Tray

Make wax spacers

2 mm cutback1 thickness wax

Roll out tray material.

Adapt tray material and

form a handle.

Making a Custom Tray

1.Trim off excess acrylic.

2. Trytray oncast.

3.Observe the tray handle.

Finished TraysFingerRests

Finger rests are placed on traysfor severely atrophic mandibles.

Finished Trays

9-10mm

6-7mm 11-12mm

Finished Mandibular Trays

Triad Trays

Adapt tray material to casts and trim any excess material.

Triad Tray Finished

Finished Tray

Tray is cut backto the 2mm wax

spacer.

Wax is leftin place until

border moldingis completed.

Note the sizeand shape ofthe handles.

Tray ExtensionsBefore the finalimpressions are madeALWAYS check thetrays for proper fitand extension.

Fitting the tray

Fitting the tray

Fitting the tray

Fitting the trayPoints to relieve in the mouth.

Modeling Plastic•Gray or green•Water bath•128-135oF•Ice

Armamentarium

Border Molding

Making an impressionof the vestibule duringfunction.

•Selective pressure

Fitting the tray

TemperAlways remember to temper the compound

in a water bath before placing it in the mouth to avoid serious burns.

Border Molding•Temper in waterbath 3-5 sec. thenplace in the mouthafter removal.

•Trim

Muscle Trimming

stable. no tray displacement.no tissue impingement.

Border mold the mandibular tray first.

•Less chance of gagging patient.•Patient is more cooperative.•Familiarizes patient with procedure.•Allays apprehension.

•Start by doing small areas.•Do the critical areas first.

• Lingual Frenum• Labial Frenum• Buccal Frenum

Functional Border Molding

Sublingual Roll

Border Molding

Function Check

Functional Border Molding

Buccal Frenum

Heat with alcohol torch.

Temper, then muscle trim again.

As you gain more skill andbecome more confident thentry the following technique.

Start by border molding

the labial and buccalflanges on the mandibular.

Do one side of the lingualflange before moving to

the other side.

Move to the other sideand finish that side of

the lingual flange.

Finish the lingual frenum area of the mandibular denture by having the pt. thrust out his tongue.

Heat with alcohol torchto soften selected areasand replace in mouth.

Remove the wax spacerprior to making impression.

Border Molding Maxillary

Do Anterior First.

Muscle Trimthe maxillary

custom tray in the mouth.

First do one side...

...then the other.

Finish with the postpalatal seal.

Border-Molded Maxillary Tray

Properly Border-moldedMaxillary Trays

Polyether Technique

Polyether impressionmaterial can also beused for border-molding the final tray.

Polyether Technique•Advantages

•Disadvantages

•Reduces overextension.•Quick

•Cost•Taste

Polyether•It is critical that thetrays are madecorrectly.

•2mm shy of fornixof vestibules.•2mm thick.

Polyether

Paint on adhesive.Mix impression material.

PolyetherA

B

C

A.Load tray with polyether impression material.B. Place tray in mouth.C. Borders of tray are defined by impression.

Polyether

Follow the same procedure for themaxillary impression. The most obvious difference between the twotrays is that the maxillary border molding does not cover the tray.

Polysulfide

Impression

Polysulfide•Remove Wax•Trim MP•Tray Adhesive

FinalImpression

•Ready to make finalimpression.

•Trays are retentive.•Borders are finished.

Impression•Final impressions are:

•Of uniform thickness.•(1mm)•Free of voids.•Contoured over ridge.

Impression•Possess excellantsurface detail.•Not be too thick atthe borders (25mm)or overextended.

Procedure

After the border molding is completed the spacer wax isremoved and the tray is painted with adhesive.

Wax spacer is removed.

Adhesive is painted on.

ARMAMENTARIUM FOR FINAL IMPRESSION

Procedure

The patient isseated in theupright position.

•Mouthwash•Reduce the saliva.

Procedure

The patient isasked to suckon a piece ofice to reducethe function of the palatine glands.

Procedure

Approximately 3-3.5 inches oflight body Permalastic is used to make the impression.

Procedure

Procedure

Loading the impression tray.

Procedure

FUNCTIONAL MOVEMENTS

Mandibular Impression

“Show-through” of border molding

The filled tray.

Muscle trim.

Procedure

The impression is heldin place for 6-8 minutes.

•Tissue detail•Voids•Even thickness

Hold tray in place.

Zinc Oxide-Eugenol Paste Final Impressions

Other Types of Impressions

Polyvinylsiloxane Impression

COMPLETED FINAL MANDIBULAR IMPRESSION

HIGHLY DETAILED REPRODUCTION OF TISSUE SURFACE

Land Area

POST DAM

Advantages•Aids In retention of theupper denture.•Helps control Gagging.•Compensates for processing shrinkage.

Landmarks•Hamular Notch•Vibrating Line•Midpalatal Suture•Glandular Zone•Fovea Palatina

Vibrating Line Imaginary line across the posterior part of the palate, marking the division betweenthe moveable and immovable tissues of the soft palate.

FoveaePalatina

Two small pits, one on eachside of the mid-line, near thejunction of the hard and softpalate.

Landmarks

Hamular NotchFovea

Soft Palate

House classified the soft palateaccording to how it drapes.

House Classifications

CLI

CLII

CLIII

Soft Palate, Class I

Vibrating line

5-10 mm

Soft Palate: Class II

•Area for placement ofthe post-dam isreduced to 3-5mm.•Most common typefound in patients.

Soft Palate: Class II

Vibrating Line

Class II

3-5mm

Soft Palate: Class III

•Represents the mostlimited area.

•It usually ranges from1-3 mm.

Soft Palate: Class III

•It is easiest to locate.•Care should be takennot to overextend thedenture.

Soft Palate: Class III

1-3 mm

Vibrating line

Class III

Vibrating Line

Located within these areas according to the type of soft palate. The area must be palpated to determine how far the line can be placed.

Vibrating line

Placement Zone

CD

Class III

Bead End of Denture

Locating the Post-Dam

•Dry the area with 4X4gauze.•Palpate the tuberosity,midpalatal raphae, andhamular nitch.

Procedure

•Mark the hamularnotch with sterile inkstick.•Locate by having the patient say ‘Ah’ in short bursts.

Procedure

Palpate and mark the area of the hamular notch.

Post Dam

Procedure

Post-Dam

Procedure

Connect to vibrating line.

Procedure

Reinsert Impression.

Post-Dam

Post-Dam

Post-Dam

Post-Dam

Box and Pour•Rim, box, pour, separate, and trim the final cast.•You will need to retrace the marks on the cast sothat the post palatal seal is clearly marked.

Box and Pour

Boxing wax should extend 10 mmabove impression.

Box and Pour

Finishing land area of maxillary master cast.

Making a BaseplateSprinkle Method

•Work In sections •sift powder

•wet with monomer

Making a Baseplate

Keep wet with monomerto avoid “sugar” look.

Making a BaseplateFinger Adapted Dough Method

Forming resin well in dough stage.

Making a BaseplateFinger Adapted Dough Method

Place dough over cast and adapt it well.

Making a Baseplate

Cure in warm pressure pot@ 20 psi/20 minutes.

Making a Baseplate

Remove from cast and trim off flash.

Immediate Mandibular CD Boxed Impression and Final Cast