Orthodontics · single question
On the TENSION side of orthodontic tooth movement, which cells are primarily active?
Show answer and explanation
Correct answer: D. Osteoblasts
On the tension side, stretched PDL fibers signal osteoblasts to deposit new bone. Tension = bone formation; Pressure side = osteoclasts (resorption).
- A. ❌ Osteoclasts are active on the PRESSURE side (bone resorbed to allow movement).
- B. ❌ Chondroblasts produce cartilage; not involved in orthodontic bone remodeling.
- C. ❌ Fibroblasts maintain PDL but are not the primary bone-forming cell on the tension side.
- D. ✅ CORRECT – Tension side: osteoblasts deposit new bone.