The prognosis and evaluation of the abutment teeth is of primary importance in the preparation of a treatment plan for the patient. Factors such as probing pocket depth – clinical attachment loss, mobility, crown to root ratio, root morphology, furcation involvement and root proximity, as well as mucogingival problems should be thoroughly examined. The classical way of evaluating teeth froma prosthetic point of view is based on their ability to withstand forces, the crown to root ratio, their position in the arch as well as on the degree of carious lesions. Themost significant problems in a treatment plan are wrong diagnosis and insufficient treatment of endodontic problems. The correct treatment of pulp diseases as well as of the problems arising in the periapical tissues constitute a prerequisite for the successful periodontal and prosthetic rehabilitation. Finally, the patient is an important factor determining the successful outcome of the total rehabilitation.