Healing

===Proliferative phase===
In the proliferative phase, immature [[granulation tissue]] containing plump, active fibroblasts forms. Fibroblasts quickly produce abundant type III [[collagen]], which fills the defect left by an open wound. Granulation tissue moves, as a wave, from the border of the injury towards the center.{{Citation needed|date=May 2022}}

As granulation tissue matures, the fibroblasts produce less collagen and become more spindly in appearance. They begin to produce the much stronger type I collagen. Some of the fibroblasts mature into myofibroblasts which contain the same type of [[actin]] found in [[smooth muscle]], which enables them to contract and reduce the size of the wound.{{Citation needed|date=May 2022}}