If the tooth is decayed to the point where only the root is left, if the root is long and there is no inflammation, root canal treatment is required, followed by crown restoration or denture installation. If the root of the tooth is short and there is inflammation, the root of the tooth needs to be extracted and treated with dental implants or dentures. If the tooth is rotten to the point that only the root is left, dental radiographs will be taken to check the root condition. If the root is long, the edge of the root is located on the edge of the gums, and there is no inflammation, root canal treatment can be carried out first, and then crown restoration treatment can be carried out. If the patient has inflammation in the roots, or if the roots are short and the edge of the roots are below the gum margin, the roots will need to be extracted. After the root is removed, dental implants, removable dentures or porcelain bridges can be used for restorative treatment. It is recommended that the patient’s teeth are rotten only to the roots need to consult a doctor in a timely manner, the doctor will choose the appropriate measures according to the patient’s dental condition treatment. Patients usually need to keep their mouth clean, need to develop the habit of brushing their teeth in the morning and evening, and need to rinse their mouths in time after each meal to avoid food residues in the mouth.