The professional term of tooth decay is called tooth decay, according to the different degree of decay, different treatment methods are needed; 1, the cavity is relatively small, and there is no spontaneous pain and obvious hot and cold stimulation pain, this case only needs to remove the decayed tooth tissue, and then fill the defective part with filling material; 2, the cavity is large or deep and there is spontaneous pain or obvious hot and cold stimulation pain, root canal treatment and then cavity filling is needed, generally After root canal treatment, the brittleness of the tooth will become bigger as time lengthens, so in order to prolong the service life, it is better to put a crown on the tooth after root canal treatment to avoid tooth fracture, because once the tooth is fractured, it may need to be extracted; 3.When the caries is extensive or only the root is left, the root still has retention value, so it can be restored by pile crown after root canal treatment, if it has no retention value, it needs to be extracted. If there is no retention value, the tooth needs to be extracted and restored 2-3 months after extraction, that is, to set dentures or do dental implants.