Download - 14. Altered Cast
![Page 1: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/1.jpg)
Altered Cast TechniqueAltered Cast Technique
![Page 2: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/2.jpg)
Altered Cast TechniqueAltered Cast Technique
• Corrected Cast
• Modified Cast
• Corrected Cast
• Modified Cast
![Page 3: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/3.jpg)
Altered Cast ImpressionsAltered Cast Impressions
• Impression of residual ridge
• Custom impression tray attached to the framework
• Impression of residual ridge
• Custom impression tray attached to the framework
![Page 4: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/4.jpg)
PurposePurpose
• Impression is used to modify master cast
• More accurate relationship between abutments & ridge
• Equalize stress between ridge and abutments
• Correct peripheral adaptation
• Impression is used to modify master cast
• More accurate relationship between abutments & ridge
• Equalize stress between ridge and abutments
• Correct peripheral adaptation
![Page 5: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/5.jpg)
When NeededWhen Needed
• Framework most likely adjusted
• Class I & II - relationship most N.B.
• Extensive Class III & IV cases
• Tooth mobility + compressible mucosa
• Less necessary in maxilla
• Framework most likely adjusted
• Class I & II - relationship most N.B.
• Extensive Class III & IV cases
• Tooth mobility + compressible mucosa
• Less necessary in maxilla
![Page 6: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/6.jpg)
Impression TechniqueImpression Technique
• Well Fitting Framework
• Place relief over ridge– 1 mm wax relief
– Separator (Alcote)
– Heat and fully seat framework
• Well Fitting Framework
• Place relief over ridge– 1 mm wax relief
– Separator (Alcote)
– Heat and fully seat framework
![Page 7: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/7.jpg)
Check SeatingCheck Seating
• If not seated, remove, repeat– Rests fully seated
– Tissue stop contacts cast
– Metal adjacent abutment contacts cast
– No resistance as framework seated
• If not seated, remove, repeat– Rests fully seated
– Tissue stop contacts cast
– Metal adjacent abutment contacts cast
– No resistance as framework seated
![Page 8: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/8.jpg)
Check PeripheriesCheck Peripheries
• 2-3 mm short of vestibular
• No displacement when: – Pull on cheeks, lips
– Patient activates tongue
• 2-3 mm short of vestibular
• No displacement when: – Pull on cheeks, lips
– Patient activates tongue
![Page 9: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/9.jpg)
Border MoldBorder Mold
• Simulate final denture border• Simulate final denture border
![Page 10: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/10.jpg)
Make Altered Cast ImpressionMake Altered Cast Impression
• Ensure tray is well retained by framework
• Remove wax spacer
• Coat tray with adhesive
• Wait 10-15 minutes
• Ensure tray is well retained by framework
• Remove wax spacer
• Coat tray with adhesive
• Wait 10-15 minutes
![Page 11: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/11.jpg)
Altered Cast ImpressionAltered Cast Impression
• Polyvinyl siloxane– Light or medium body
• Carefully load tray• No material under rests,
g.p.’s, max. major connector, etc.
• Seat with pressure over rests
• Polyvinyl siloxane– Light or medium body
• Carefully load tray• No material under rests,
g.p.’s, max. major connector, etc.
• Seat with pressure over rests
![Page 12: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/12.jpg)
No Pressure Over GridworkNo Pressure Over Gridwork
• Fulcruming or tissue compression
• Spring back and lack of tissue contact
• Fulcruming or tissue compression
• Spring back and lack of tissue contact
a
spring-backpressure
![Page 13: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/13.jpg)
Remove & Inspect ImpressionRemove & Inspect Impression
• Absence of voids
• Minimal burnthrough
• Covers supporting tissues
• Fully seated, etc.
• Absence of voids
• Minimal burnthrough
• Covers supporting tissues
• Fully seated, etc.
![Page 14: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/14.jpg)
Send to LaboratorySend to Laboratory
• Lab Steps– Section residual ridge from cast
– Ensure no contact between impression & cast
– Place retentive grooves in cast
– Sticky wax in place
• Lab Steps– Section residual ridge from cast
– Ensure no contact between impression & cast
– Place retentive grooves in cast
– Sticky wax in place
![Page 15: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/15.jpg)
Lab StepsLab Steps
– Box impression
– Ensure water tight seal
– Seal retainer, major & minor connector borders
– Pour new ridge areas in different color stone
– Box impression
– Ensure water tight seal
– Seal retainer, major & minor connector borders
– Pour new ridge areas in different color stone
![Page 16: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/16.jpg)
Problems with the Altered Cast Technique
Problems with the Altered Cast Technique
• If tray is added carelessly, it can alter passive relationship
• Excess impression material under framework
• If inadequately sealed, stone over teeth, can’t articulate model
• If tray is added carelessly, it can alter passive relationship
• Excess impression material under framework
• If inadequately sealed, stone over teeth, can’t articulate model
![Page 17: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/17.jpg)
Record Base for Wax SetupRecord Base for Wax Setup
• Place Denture Base– Hard baseplate wax
• Easier to remove during processing
• Can melt or distort
– Acrylic resin• Harder to remove• More rigid and stable for jaw
relation
• Place Denture Base– Hard baseplate wax
• Easier to remove during processing
• Can melt or distort
– Acrylic resin• Harder to remove• More rigid and stable for jaw
relation
![Page 18: 14. Altered Cast](https://reader036.vdocument.in/reader036/viewer/2022081413/547805cfb4af9f63108b4a86/html5/thumbnails/18.jpg)
Jaw Relation RecordsJaw Relation Records
• Mount Casts on Articulators– Facebow / Earbow Record
• Maxilla to hinge axis
– Centric Record• Maxilla to mandible position
– Protrusive Record• Program articulator for excursions
• Mount Casts on Articulators– Facebow / Earbow Record
• Maxilla to hinge axis
– Centric Record• Maxilla to mandible position
– Protrusive Record• Program articulator for excursions