What is the difference between a full-thickness skin graft and a skin flap?

the difference between a graft and flap is that one is free and the other one has a pedicle attached to its original place. The graft needs the area blood supply to survive but the flap has its own blood supply. The full thickness graft, has the subcutaneous fat and muscles with the skin graft. We worry about strangulation of blood supply in the flap. When we planing the movement of the flap, we should consider the blood supply of the flap as well. 

A skin graft is a free piece of skin that is excised, removed and thinned before being inset into a wound whereas a flap is tissue around a wound that is rearranged and positioned to fill a defect in the local area. Both work great when used appropriately. If you have a skin cancer surgery coming up discuss with your dermatologist or your plastic surgeon if you've been referred to another doc for Mohs reconstruction. I hope this information is helpful for you.Stephen Weber MD, FACSDenver Facial Plastic Surgeon

Dr. Harris gave a good review of the defining characteristics that differentiate a full thickness skin graft from a skin flap.Keep in mind that the term skin flap encompasses a huge variety of options.  There is also some variability in the ways to perform a full thickness skin graft but not nearly as much variation when it comes to flap options.To further answer your question I'll touch on each of the points you asked about:1. ProcedureAs mentioned and in the most general terms, a GRAFT is separated from the body and reattached while a FLAP maintains a partial connection to its blood supply and is then used to close a defect.A full thickness skin graft is overall a much more simple procedure in terms of complexity.  Skin "flaps" range from very simple and straightforward to some very intricate complex options depending on the defect needing to be closed and its location.2. HealingBoth options typically heal well.  A skin flap has a much better rate of graft take or survival because of its inherent better blood supply.  Issues like having diabetes, being a smoker, or having peripheral vascular disease will greatly increase the potential for poor healing with a full thickness skin graft (or a skin flap for that matter).3. PurposesBoth are good options -- it really depends on what the defect is and where it is located.  A full thickness skin graft is a less complex option which can be used to keep things simple and avoid a longer more complex procedure.  Some of the decision making also comes down to aesthetics.4. Aesthetic OutcomeSometimes a skin flap is preferred, not only because of better blood supply, but also because the skin adjacent to a defect that is being rotated in is usually a very good color and texture match. However, full thickness grafts taken from certain areas can match very well to specific defect areas.Sometimes a full thickness graft will have a higher rate of scar contracture.  With both types of procedures you can get other issues related to swelling that we call trap door deformities or pin cushioning.Overall, a flap is a better aesthetic option for the majority of defects in my opinion, but I continue to use full thickness grafts in certain situations when indicated and the aesthetic results can be very good.