Does bone have excellent capacity for self-repair?

• A. No
• B. Only after fracture
• C. Yes
• D. Only with grafts

Answer: (C)

Bone has a remarkable ability to repair itself because its tissue is highly cellular and well supplied with blood, enabling a coordinated healing process. When injury occurs, inflammation brings cells and blood flow to the area, forming a stabilizing hematoma. The periosteum and bone marrow provide osteoprogenitor cells that become osteoblasts, laying down new bone. A soft callus forms first and mineralizes into a hard callus, then remodeling reshapes the area by replacing temporary woven bone with organized lamellar bone, restoring strength and structure as the bone is used again. This self-repair happens after fractures and many other injuries without needing grafts, which is why bone is said to have excellent regenerative capacity. Of course, very large defects, poor blood supply, infection, or systemic conditions can hinder healing and may require grafts or other interventions, but the inherent repair ability is strong.