Wound healing is the process that the skin goes through as it repairs damage from wounds. 

There are three main types of wound healing: primary, secondary and tertiary wound healing.

PRIMARY INTENTION

A surgical wound that heals by primary intention has these characteristics:

• wound edges are close together and held together with sutures, staples, or surgical glue;
• the wound is not infected;
• the healing process takes place in a few days.
• Refers to when doctors close a wound using staples, stitches, glues, or other forms of wound- closing processes.

SECONDARY INTENTION

Refers to when a wound that cannot be stitched causes a large amount of tissue loss. Doctors will leave the wound to heal naturally in these cases.

In some cases, due to the risk of infection, the wound is left open to allow healing by secondary intention.

This type of surgical wound has these characteristics:

• the wound margins are displaced (due to the risk of infection or significant tissue loss it is not possible to approach the margins and the surgical wounds are thus left open).
• there is loss of substance or there is a suppurative complication
• the healing process takes longer than healing by primary intention (missing or non-viable tissue must be replaced by new cells)
• the resulting scar is certainly more evident and can have variable shapes.

TERTIARY INTENTION

Refers to the delayed of primary closure, occurs when there is a need to delay the wound-closing process.

A wound that heals by third intention has these characteristics:

• the wound has undergone an infection or partial or total dehiscence immediately after suturing;
• it is necessary to reopen the wound for cleansing and cleaning of organic residues and necrotic tissues;
• the wound is sutured again after a few days and after an assessment of the local situation and after excluding the presence of outbreaks of infection;