CIT Implant Materials & Techniques 2 — Questions and Answers
Question 1: Which surface treatment creates a micro-rough titanium implant surface through controlled chemical etching?
- Acid etching with HF/HNO3 (Correct answer)
- Sandblasting alone
- Plasma spraying
- Electropolishing
Correct answer: Acid etching with HF/HNO3
Acid etching with hydrofluoric/nitric acid removes surface layers to create a micro-rough topography that enhances osseointegration.
Question 2: The SLA (sandblasted, large-grit, acid-etched) surface modification is primarily designed to:
- Reduce implant cost during manufacturing
- Increase surface area for bone cell attachment (Correct answer)
- Improve radiopacity on imaging
- Decrease bacterial colonization
Correct answer: Increase surface area for bone cell attachment
SLA treatment creates a micro-rough surface with increased surface area that promotes osteoblast adhesion and accelerates osseointegration.
Question 3: Hydroxyapatite (HA) coating on implants is derived from which mineral compound?
- Calcium phosphate (Correct answer)
- Titanium oxide
- Zirconium dioxide
- Aluminum oxide
Correct answer: Calcium phosphate
Hydroxyapatite is a calcium phosphate ceramic that mimics the mineral component of natural bone, promoting direct bone bonding.
Question 4: What is the primary disadvantage of plasma-sprayed hydroxyapatite coatings on titanium implants?
- Poor initial stability
- Risk of coating delamination over time (Correct answer)
- Increased cost of zirconia
- Reduced biocompatibility
Correct answer: Risk of coating delamination over time
Plasma-sprayed HA coatings can delaminate from the titanium substrate over time, potentially releasing particles and compromising long-term stability.
Question 5: Which implant macro-design feature most directly influences primary stability in low-density bone?
- Implant length
- Thread depth and pitch (Correct answer)
- Platform diameter
- Collar height
Correct answer: Thread depth and pitch
Deep threads with appropriate pitch maximize bone engagement in type III/IV bone, significantly improving primary stability during placement.
Question 6: Titanium Grade 4 differs from Grade 5 (Ti-6Al-4V) primarily in that Grade 4:
- Contains aluminum and vanadium alloys
- Is commercially pure with higher strength than Grade 1-3 (Correct answer)
- Has superior fatigue resistance for narrow implants
- Is the preferred choice for all posterior implants
Correct answer: Is commercially pure with higher strength than Grade 1-3
Grade 4 is commercially pure titanium with the highest strength among CP-Ti grades, while Grade 5 is an alloy with added aluminum and vanadium.
Question 7: The galvanic corrosion risk is most relevant when:
- A zirconia implant is restored with a titanium abutment
- Two titanium components from different manufacturers are joined
- A titanium implant is combined with a gold alloy crown (Correct answer)
- All-ceramic restorations are placed on titanium implants
Correct answer: A titanium implant is combined with a gold alloy crown
Galvanic corrosion occurs when dissimilar metals (titanium implant and gold alloy crown) are in contact in an electrolytic environment like saliva.
CIT Implant Materials & Techniques 2
Which surface treatment creates a micro-rough titanium implant surface through controlled chemical etching?