Dental Implants Prosthetic Restoration 1 — Questions and Answers
Question 1: Which impression technique captures the three-dimensional position of implants in the mouth using a tray that remains in the mouth during cast separation?
- Closed-tray impression
- Open-tray (pick-up) impression (Correct answer)
- Alginate irreversible hydrocolloid technique
- Bite registration technique
Correct answer: Open-tray (pick-up) impression
Open-tray (pick-up) impressions transfer impression copings out with the tray, providing more accurate positional transfer especially for multiple implants.
Question 2: Digital implant impressions using intraoral scanners compared to conventional impressions offer:
- Lower accuracy for multiple implants
- Elimination of physical impression materials and improved patient comfort (Correct answer)
- Requirement of impression copings still
- Limited use to single tooth cases only
Correct answer: Elimination of physical impression materials and improved patient comfort
Digital scan abutments and intraoral scanners eliminate messy impression materials and provide digital workflows directly to CAD/CAM fabrication.
Question 3: An implant-supported fixed partial denture (implant bridge) requires at least how many implants per pontic to maintain appropriate force distribution?
- One implant total is sufficient
- Ideally one implant per tooth replaced, but minimum one at each end (Correct answer)
- Three implants regardless of span
- One implant per pontic unit always
Correct answer: Ideally one implant per tooth replaced, but minimum one at each end
Standard practice supports a bridge with at least one implant at each end of the span, though longer spans may require intermediate implants.
Question 4: The emergence profile of an implant crown refers to:
- The angle of the implant in the bone
- The contour of the restoration as it emerges from the gum tissue (Correct answer)
- The height of the crown above the gum
- The shade of the porcelain used
Correct answer: The contour of the restoration as it emerges from the gum tissue
The emergence profile is the three-dimensional transition between the implant abutment and crown as it exits the peri-implant sulcus, affecting esthetics and hygiene access.
Question 5: Which prosthetic material is most commonly used for implant-supported crowns in the posterior region due to its strength?
- Composite resin
- Full-cast gold
- Monolithic zirconia (Correct answer)
- Feldspathic porcelain
Correct answer: Monolithic zirconia
Monolithic zirconia is preferred posteriorly for its high fracture resistance, low chipping rate, and excellent wear properties under heavy occlusal load.
Question 6: The screw access channel in a screw-retained implant crown is typically sealed with:
- Permanent composite resin
- Polytetrafluoroethylene (PTFE) tape and composite (Correct answer)
- Zinc oxide eugenol cement
- Glass ionomer cement only
Correct answer: Polytetrafluoroethylene (PTFE) tape and composite
PTFE tape placed below a composite resin plug allows the access channel to be opened for retrieval while protecting the screw head.
Dental Implants Prosthetic Restoration 1
Which impression technique captures the three-dimensional position of implants in the mouth using a tray that remains in the mouth during cast separation?