Impression Techniques

Question 1

Implants: General Impression info

Answer 1

• after osteointegration
• record all dimensions accurately
• easier than natural teeth
  
  • but Less forgiving (No PDL)

Question 2

Implant body

Answer 2

• Aka Implant fixture screw or cylinder
• part of implant in bone

Question 3

Impression Coping

Answer 3

• transfer implant position to cast
• used during impression

Question 4

Impression Analog

Answer 4

• Implant replica
  
  • used on the cast

Question 5

Tight Contacts: (b/w implant & teeth)

Answer 5

• Increase stress
  
  • No PDL→ Never neutralized
• prevent complete seating of restoration
• Complications:
  
  • biological→ Bone Loss
  • Mechanical→ Screw Loosening

Question 6

What are the different types of impression techniques for implants?

Answer 6

• Implant Level (deeper)
  
  • High Esthetic cases
    
    • Anterior Implants
  • Recreates gingival tissues
    
    • uses resin
  • Types:
    
    • Open Tray (Direct Coping Transfer)
      
      • Splinted vs Non-Splinted
    • Closed Tray (Indirect Coping Transfer)
    • Customized Impression transfer technique
• Abutment Level (shallower)
  
  • use w/Solid Abutments
    
    • final abutment delivered and temporized
    • allows for healing to go ahead and start
  • Impression coping “clicks” onto abutment
  • Types:
    
    • Direct
    • Indirect
• Digital Impression

Question 7

Open Tray Impressure

Answer 7

• Implant level impression (Deeper)
• Direct Coping Transfer
  
  • pick-up impression
• Coping:
  
  • long retaining screw that goes through tray
  • unscrew when impression material set
• Limits:
  
  • hard to seat inside mouth so that screw goes through hole
  • Posterior region (more difficult)
• Non-Splinted:
  
  • Copings: Not Connected
  • Limits:
    
    • Movement→inaccurate relationship of implants
• Splinted:
  
  • Copings: Connected w/resin or composite
  • Limits:
    
    • time consuming
    • technique sensitive
      
      • Material shrinkage

Question 8

Closed Tray Impressions

Answer 8

• Implant Level impressoins (Deeper)
• Indirect Coping Transfer
• Limits:
  
  • Transfer process:
    
    • incorrect orientation
    • inaccuracies

Question 9

Custom Impression

Answer 9

• Implant level impression
• Modified open tray impression
• Esthetic Zone
  
  • better emergence profile & soft tissue contours
• Anterior Teeth emergence profile
  
  • supports soft tissue→ Superior esthetics
• Rapid Tissue collapse after temporary crown is removed

Question 10

Emergence Profile

Answer 10

• transition from circular implant diameter to restoration contours
  
  • “Running Room”

Question 11

Custom Impression Transfer Technique

Answer 11

1. Unscrew Temporary Restoration
2. Screw Temp on analog
3. Place Temp/Analog in plastic cup filled with Bite Registration
4. Remove temporary (analog stays in bite registration)
5. Connect Impression Coping to Analog
   
   1. fill gap b/w bite registration and coping w/autopolymerizing acrylic resin
6. unscrew customized impressions coping from analog
7. Seat Impression coping on implant intra-orally
8. Take impression

Question 12

Abutment Level Impression

Answer 12

• Closed Tray Impression Technique
• use with Solid abutments
• Final abutment is delivered & temporized
  
  • allows healing to go ahead and start
• Impression coping “clicks” onto abutment
• Limits:
  
  • Prefab abutments can’t be used with:
    
    • severe implant angulation
    • Deep implant platforms
• Direct vs Indirect

Question 13

Digital Impressions

Answer 13

• 2004
  
  • coded healing abutment
  • provides 3D info on implant location to:
    
    • adjacent teeth
    • opposing dentition
    • soft tissue
• Scan Body

Question 14

Digital Impression: Scan Body

Answer 14

• translates implant position to digital file
• same fxn as impression coping
• require intraoral scanner (IOS) to collect data (point clouds=3D coordinates)