When a child breaks a deep wound, whether or not it will leave a scar depends on the depth of the wound, whether or not the wound is infected, nutritional factors, and the neatness of the wound. Whether a wound will leave a scar or not does not depend on the depth of the wound alone, but is related to the multiple factors mentioned above. For example, if the wound is deeper and has injured the hair layer of the skin, it can lead to scarring. In addition, if the wound is locally infected, it can also lead to prolonged healing and scarring. Malnourished babies, as well as babies with uneven wounds mixed with small foreign objects, can also lead to scar formation. Therefore, if a child knocks a deep wound, it can be debrided under the guidance of a doctor and sutured if necessary. Nutrition should be strengthened and infection avoided to minimize the possibility of scarring.