Final answer:
Third-degree and fourth-degree burns are critical injuries that require immediate medical attention due to the depth of the tissue damage and the risk of significant complications.
Step-by-step explanation:
Third-degree and fourth-degree burns always require immediate medical attention. A third-degree burn completely destroys the epidermis and dermis layers of the skin, including the nerve endings and sensory function, while a fourth-degree burn extends damage to the underlying muscle and bone. These disorders are not only serious due to the depth of tissue damage but also because they can lead to significant fluid loss, infection, and other critical complications. Immediate medical care is crucial to manage the injury, prevent complications, and commence the healing process which often involves excision (debridement), or in severe cases, amputation followed by skin grafting from an unaffected part of the body or from skin grown in tissue culture for grafting purposes.