Toenails growing into the flesh is most commonly caused by onychomycosis, which is usually caused by accidentally damaging the soft tissues around the nail groove when clipping the nails, but not strictly sterilized, which leads to bacterial infection and inflammation inside. Alternatively, it can be caused by accidental injury to the toenail while walking or playing sports, which causes wounds to the surrounding soft tissues and without formal care, thus leading to infectious inflammation. In this case, you can choose conservative treatment or surgical treatment. Conservative treatment is to strictly disinfect the local area and apply some disinfectant solution, commonly iodine vapour, or topical anti-inflammatory ointment. If active surgical treatment, usually in the toe after local anesthesia to pull out the long into the flesh of the nail, and then thoroughly clean inside the infected tissue, so as to be able to completely cure.