Old teeth rotting empty need to go to the hospital to check the size of the residual tooth, according to the condition of the tooth to consider tooth extraction or root canal treatment after dental crowns stump core crown restoration. 1. Extraction. If most of the tooth is decayed to subgingival or decayed to the root of the tooth, the tooth can not be treated with root canal therapy, and the tooth has no value to be retained, it is recommended to extract the tooth and then prosthetic restoration. 2. Root canal treatment. Tooth caries but not yet reached the subgingival, the root length is good, the tooth has the value of retention, can be root canal treatment in the tooth after staking, and then above the crown repair. Tooth rotten empty recommended timely to the hospital to check the condition of the tooth, to avoid caries continue to develop leading to inflammation aggravate the impact of oral health.