True.
I have the opportunity to travel a fair amount and give many talks and presentations on health myths and misconceptions. I routinely ask participants in those talks if they think it is best to uncover a wound and let it air out at certain times (e.g., when going to bed). I would say that 95% of those I ask think it is a good practice to uncover wounds and let them dry out as they think this promotes healing. It’s no surprise so many people have this misconception, as mothers and fathers have been telling their children this for years. Before researching this topic, I actually told my children the same thing. Keeping a wound covered will keep the area moist and promote new tissue (cell) growth. Not covering a wound, and having it dry out, usually results in increased scab formation, which can lead to increased scarring. Scabs also slow the rate of healing as healthy regenerative tissue has a more difficult time covering a wound if it is scabbed over. Keeping a wound covered also decreases the risk of infection as a covering will help keep dirt and bacteria out of the wound. Finally, a covering will help reduce the risk of re-injury. Most of us have had the unpleasant experience of having a scab break open or tear off or have a wound re-open because it gets bumped or scrapped up against something, a covering can help prevent this from happening. Well designed research studies have shown that covering a wound usually increases healing rates by 3 to 4 days. Dr. Joel Beam (2008) did a study where he created abrasions with sandpaper on research participants (doesn’t that sound like fun). Dr. Beam covered some wounds but also left some uncovered and concluded that covering wounds significantly increases healing rates. So, tell your children to keep those wounds covered, even when they go to bed!
Reference:
Beam J: Occlusive dressings and the healing of standardized abrasions. Journal of Athletic Training (2008), Vol. 43, pps. 600-607.