Implants · single question
A 45-year-old male is interested in implant placement. Each of the following is a cytokine that aids in the stability and success of an implant EXCEPT one. Which is the EXCEPTION?
Show answer and explanation
Correct answer: A. Interleukin-1
TGF-β1 and BMP-4 promote bone formation and healing around implants. TNF-alpha, while pro-inflammatory, plays a complex role but when chronically elevated is detrimental. IL-1 is strongly pro-inflammatory and when elevated chronically leads to bone resorption and implant failure — it is the cytokine that does NOT aid implant stability.
- A. CORRECT. Interleukin-1 (IL-1) is a pro-inflammatory cytokine. Chronically elevated IL-1 stimulates osteoclasts and promotes bone resorption, which is detrimental to implant osseointegration and stability.
- B. INCORRECT. BMP-4 (Bone Morphogenetic Protein-4) is osteoinductive — it directly stimulates osteoblast differentiation and bone formation, strongly AIDING implant stability.
- C. INCORRECT. TNF-alpha has complex roles but can promote early healing; it is also pro-inflammatory and when chronically elevated can harm implants. IL-1 is the better 'exception' answer.
- D. INCORRECT. TGF-β1 (Transforming Growth Factor beta-1) promotes extracellular matrix production, cell proliferation, and bone healing — it AIDS implant stability.
Note: ⚠️ FLAG: The source lists IL-1 as the exception. IL-1 and TNF-α are both pro-inflammatory. IL-1 is the better answer here as it is most consistently associated with peri-implant bone loss when overexpressed.