If it is certain that a wound requires stitches, WebMD recommends that the wound not remain open for longer than six to eight hours after the injury occurs. In rarer cases, a wound may be left open for 24 hours or not stitched at all so that adequate cleaning and antibiotic treatment can be performed initially to prevent infection. Clean cuts may be able to wait 12 to 24 hours.
It is very important to have an open wound closed as soon as possible if stitches are required except when a doctor advises to leave it open under medical supervision. Injuries requiring stitches can become infected if not treated soon enough. It is best to visit a doctor to determine if a wound needs stitches, but there are some telling signs that people can use to gauge the seriousness of a wound. For example, WebMD says that deep wounds more than 0.25 inches into the flesh may need to be stitched, especially if they reach down to the fat, muscle, bone or other deep structures.
Wounds in areas where scarring is a concern for cosmetic reasons should be stitched, such as on the face and lips. Wounds that continue to bleed after 15 minutes of direct pressure may also require stitches, notes WebMD.