Depth of burn injury in relation to skin level Depth of burn injury in relation to skin level. First-degree burns involve the epidermis, second-degree burns involve the epidermis and dermis, third-degree burns penetrate to the subcutaneous tissue, fourth-degree burns extend to the muscle layer. Key structures imbedded in each layer are indicated. (Reproduced with permission from Garner WL: Thermal burns. In: Achauer BM, Eriksson E, eds. Plastic Surgery: Indications, Operations, and Outcomes. St Louis, MO: Mosby, 2000;361. Copyright © Elsevier.) Source: Burns and Other Skin Injuries, Comprehensive Pediatric Hospital Medicine, 2e Citation: Zaoutis LB, Chiang VW. Comprehensive Pediatric Hospital Medicine, 2e; 2017 Available at: http://accesspediatrics.mhmedical.com/DownloadImage.aspx?image=/data/books/2216/zaoutis2_ch162_f001-1.png&sec=170339173&BookID=2216&ChapterSecID=170339163&imagename= Accessed: October 19, 2017 Copyright © 2017 McGraw-Hill Education. All rights reserved