多根管后牙不可复性牙髓炎及根尖周炎治疗的探讨（附２９９牙例）新乡医学院第三附属医院口腔科（４５３０００）刘军新乡市公费医疗医院口腔科孙太升自１９８９年以来，作者对同一多根管后牙采用根管治疗与干髓术治疗联合术（简称根一干联合术）或根管治疗与空管药物疗法... Multiple root canal posterior teeth irreversible pulpitis and periapical periodontitis treatment (attached to 299 cases) Department of Stomatology, Third Affiliated Hospital of Xinxiang Medical College (453000) Liu Jun Xinxiang City Public Medical Hospital Department of Stomatology Sun Taisheng since 1989 Since the author of the same root canals with root canal therapy and dry pulp surgery combined with surgery (referred to as dry root combined surgery) or root canal therapy and empty tube drug therapy ...