plastic surgery, surgical repair of congenital or acquired deformities and the restoration of contour to improve the appearance and function of tissue defects. Development of this specialized branch of surgery received impetus from the need to repair gross deformities sustained in World War I. By the grafting of tissue or the use of artificial materials such as silicone, some remarkable restorations have become possible. Severe burns and the removal of fairly extensive skin cancers leave scars that must be covered by skin grafts; breast reconstruction after mastectomy is another application.
In addition to correcting a disfigurement, plastic surgery is often needed to restore vital movement and function of tissues that have been destroyed. It is also performed for purely cosmetic purposes, such as improving the shape of a nose, bringing outstanding ears closer to the head, or lifting the skin to erase wrinkles, and the term cosmetic surgery is often used to refer to such surgical procedures. Modern plastic surgeons often employ CAT scans to produce computer-generated images that are used to plan or simulate complex reconstructive surgeries, and 3D printers have been used to create implants for such surgeries.