Objective: To evaluate radiographic measurements for use as prognostic factors for healing of class II furcation defects following regenerative therapy. Material & Methods: In 17 patients (8 female), 33 class II furcation defects [mandibular buccal (n = 12) and lingual (n = 12), and maxillary buccal (n = 11)] were treated using the barrier membrane technique. 26 furcations were treated using a bioabsorbable membrane, while a non-resorbable membrane was used to treat the remaining 7 furcation defects. Clinical parameters and standardized radiographs were obtained before as well as 6 and 24 months after therapy. All radiographs were digitised and evaluated by an examiner blinded to the clinical data. The following distances were measured: cemento-enamel junction line (CEJ-line) to alveolar crest (AC) at the furcation site (AC-CEJ line), CEJ-line to the furcation fornix (Fx-CEJ line), width of the furcation at the level of the AC (FW) as well as the distance from Fx to a straight line between the AC mesial and distal of the tooth (Fx-AC line). Results: Statistically significant (p Conclusion: The analysis of presurgical radiographs may yield information on the success of regenerative therapy of buccal and lingual class II furcation defects. A long root trunk, a wide furcation entrance, and an Fx coronal to the AC have negative influences on the success of therapy. Further, a deep probing depth at the furcation site at baseline increases the likelihood for more favorable horizontal attachment gain in furcations. Schlagwörter: Gesteuerte Geweberegeneration, Grad-II-Furkationsdefekte, Röntgendiagnostik, Messung linearer Distanzen