Table 1.

Definition of critical-sized bone defect (CSD).

Animal	Defect Site	Dimension of CSD	References
Mouse	Calvaria	4 mm diameter	[33]
	Segmental long-bone defect	Radius: 4 mm Femur: 5 mm	[34]
Rat	Calvaria	Unilateral/central:8 mm diameter; bilateral: 5 mm diameter	[23]
	Cylindric defect	Femur: 2 mm in diameter and 3 mm in length	[35]
	Segmental long-bone defect	Radius: 1 cm diameter	[36]
	Mandible	4 mm diameter	[37]
Rabbit	Calvaria	Four defects: 8 mm diameter; unilateral defect: 15 mm diameter; bilateral defect: 11 mm diameter	[38]
	Segmental long-bone defect	Radius: defect > 1.4 cm involving periosteum	[39]
	Cylindric defect	Femur: 6 mm in diameter and 5 mm in length; tibiae: 6 mm diameter	[40] (femur) [41] (tibiae)
	Mandible	5 mm diameter	[42]
Pig	Segmental long-bone defect	Femur: 7.6 cm; tibiae: 2 cm; radius: 2.5–3 cm; ulna: 2 cm	[34,36]
Sheep	Calvaria	22 mm in diameter	[43,44]
	Segmental long-bone defect	Femur: 2.5 cm; tibiae: 3–3.5 cm	[34]
Dog	Calvaria	2 cm	[45]
	Segmental long-bone defect	Femur: 2.1–7 cm; radius: 0.3–2.5 cm; ulna: 2–2.5 cm	[34]
	Segmental mandibular defect	50 mm (in presence of periosteum); 15 mm (in absence of periosteum)	[46]