Marginal periodontitisand pulpal disease often cause similar‐appearing lesions in the periodontium. Successful therapy depends on correct diagnosis, which is sometimes difficult. Some bony defects caused by pulpal disease require surgical debridement in addition to standard endodontic therapy.With one exception three‐walled intrabony periodontal defects discussed in this report were managed by surgical debridement without any type of implant or graft. Long‐term observation is required to determine the value of techniques used in the treatment of intrabony periodontal defects.