Aim: In the present retrospektive study the situation of the natural crown as well as the restoration types placed prior to endodontic treatment was examined. Materials and methods: A total of 782 teeth from 545 patients (54.3% men; 45.7% women; mean age: 49.9 +/- 12.1 years) were investigated. In addition to the evaluation of the medical history of the patients, x-rays and a clinical investigation were carried out in order to assess the clinical condition of the crown as well as the restoration types. Of special interest were: carious lesions, composite fillings, amalgam, ceramic or gold crowns and/or bridge restorations. Results: 305 of the examined teeth were located in the mandible and 477 in the maxilla. 26.3% of the teeth were anteriors, 31.2% were premolars and 42.5% were molars. 24.2% of the teeth were restored with metal ceramic crowns, 15.1% were restored with gold cast crowns or served as abutment teeth for bridgework; untreated caries was found in 21.1%, and composite fillings were found in 13.7% of the cases. 23.8% of the front teeth, 26.6% of the premolars and 22.6% of the molars showed a metal ceramic restoration. 21% of all carious defects were found in the maxilla as well as in the mandible. Conclusions: In addition to the high number of untreated carious lesions, the presence of metal ceramics restorations was significantly higher than other restorations types. Carious lesions are main aetiological factors for endodontic measures, but also ceramic restorations including premature contacts have to be considered as causal factors for pulpal irritations.