Orthodontics · single question
Which cells are found on the TENSION side of orthodontic forces?
Show answer and explanation
Correct answer: A. Osteoblasts
Osteoblasts (A) are found on the TENSION side. Understanding orthodontic tooth movement:
• PRESSURE (compression) side: osteoclasts → bone resorption → tooth moves into this space.
• TENSION side: PDL fibers are stretched → osteoblasts activated → new bone deposition (bone fill in).
• This explains why relapse occurs if retainers are removed — bone remodeling is reversible if force is removed before full consolidation.
• Odontoblasts (C): form dentin — in tooth pulp — not involved in orthodontic movement.
• Odontoclasts (D): resorb root dentin — they CAN be stimulated by excessive/prolonged orthodontic force causing root resorption (a complication, not normal biology).
• Memory: Tension = Teeth builders (Osteoblasts) | Pressure = Pit (Osteoclasts resorb).
• PRESSURE (compression) side: osteoclasts → bone resorption → tooth moves into this space.
• TENSION side: PDL fibers are stretched → osteoblasts activated → new bone deposition (bone fill in).
• This explains why relapse occurs if retainers are removed — bone remodeling is reversible if force is removed before full consolidation.
• Odontoblasts (C): form dentin — in tooth pulp — not involved in orthodontic movement.
• Odontoclasts (D): resorb root dentin — they CAN be stimulated by excessive/prolonged orthodontic force causing root resorption (a complication, not normal biology).
• Memory: Tension = Teeth builders (Osteoblasts) | Pressure = Pit (Osteoclasts resorb).