OBJECTIVE:Clinical study was made on curative effect of medium to severe periodontal diseases as well as those complicated with partial edentulism by conical telescopic removable denture.METHODS:14 cases of medium to severe periodontal diseases and these complicated with partial edentulism were treated with prosthodontic methods after comprehensive periodontal therapy.Examinations of both before and following prosthetic restoration of 3,12,14 months were made.Bacterial plague index,gingival index,tooth movability and masticatory efficiency were recorded,analysed and compared. RESULTS:Periodontal plague attachment was under effective control through this way,which also eliminated periodontal trauma thus preventing the relapse of periodontal diseases.Further more it can diminish tooth movability and improve masticatory efficiency continuously as time goes on.CONCLUSION:Conical telescopic removable denturs is an effective prosthetic method in treating medium to severe periodontal diseases.