Classification and prognostic factors of endodontic-periodontic lesions in the dog. 
The classification of the possible pathologic relationships between the periodontium and endodontium in man includes three separate groups.  This classification system is adapted for utilization in the dog to clarify the appropriate treatment and prognosis of dog's teeth affected with endodontic-periodontic lesions.  This article describes the classification and treatment planning with illustrations of each type.