Abstract: teeth perforated into the floor of pulp cavities were treated.Among them,20 teeth showed granuloma formation in the pulp cavities.The methods of treatment included granuloma excision or fulguration. And then,iodoform gauze or iodoform with flagyl was put on the perforated area for one to two weeks.If there were no symptoms,the perforated area was filled with amalagam,glass ion cement or Dycal（radiopaque calcium hydroxide composition）.After anotber week,the root canal and broken crown were filled completely.After 1-3 years following-up,the results showed that 32 teeth were reserved and the mastication functions were good.It tells us that a teeth perforated into the floor of pulp chamber can be reserved by correct methods.