Question

Which phase must form on a biomaterial surface to promote bioactive bond?

• A. Amorphous silica
• B. Silanols
• C. Amorphous calcium phosphate
• D. Hydroxyapatite

Hint:

Hydroxyapatite formation on a biomaterial surface promotes bioactive bonding by mimicking the natural mineral phase of bone, leading to osseointegration.

Answer 1

The Correct Option is D

For a biomaterial to form a bioactive bond with bone or soft tissue, a specific biocompatible mineral layer must develop on its surface. Step 1: Understanding Bioactivity in Biomaterials - Bioactive materials are designed to interact with biological tissues and promote osseointegration. - The key factor in bioactivity is the formation of hydroxyapatite (\( Ca_{10}(PO_4)_6(OH)_2 \)), which mimics the natural mineral phase of bone.

Step 2: Evaluating the Options - Option (A) - Incorrect: Amorphous silica does not directly promote bioactivity. - Option (B) - Incorrect: Silanols are involved in surface chemistry but do not induce bioactive bonding. - Option (C) - Incorrect: Amorphous calcium phosphate is a precursor but does not provide strong bonding. - Option (D) - Correct: Hydroxyapatite is the key bioactive phase that promotes bonding with bone.

Step 3: Conclusion Since hydroxyapatite formation on the biomaterial surface is essential for bioactive bonding, the correct answer is option (D).