Authors: Simon JH, Glick DH, Frank AL.
Title: The relationship of endodontic-periodontic lesions.
Journal: J Periodontol
Date: Apr 1972
Citation: 43(4):202-8
Category: Endodontic-Periodontal Relationships
Evidence-based Ranking: 5
Purpose/Objectives: A review paper that classifies endodontic and periodontal radicular lesions based on their possible etiology, diagnosis and prognosis of treatment.

Lesions: Primary Endo - may occur with drainage from the sulcus and/or swelling in the attached gingival. Diagnostically – tooth does not respond to pulp testing, crestal bone levels on mesial and distal maybe normal, a narrow fistula tract maybe present and will heal with endodontic therapy alone. Primary Endo Secondary Perio – if the endodontic lesion remains untreated, it may become secondarily involved with periodontal breakdown. The presence of plaque/calculus during probing helps diagnose in addition to negative pulp tests. Periodontal therapy following endodontic therapy required. Primary Perio Seconday Endo – A perio lesion that progresses toward the apex allowing lateral or accessory canals to be exposed to the oral environment which can lead to pulpal necrosis. Pulpal necrosis may follow periodontal therapy that cuts the blood supply through an accessory or apical foramen. The prognosis depends on periodontal therapy following endodontic therapy. The “True” Combined Lesion – an endodontically induced periapical lesion exists on a tooth that is also periodontally involved. The infra-bony defect is created when these two entities meet and merge along the root surface. Periapical healing may follow successful endodontic therapy, but depending on the severity of the periodontal involvement, the tooth may or may not respond to periodontal therapy.

Author’s Conclusion: A classification of endodontic and periodontal lesions has been presented. To better understand and treat these problems, they discussed their diagnosis and prognosis from a clinical standpoint in order to explain the success and failure that follows treatment.

Reviewer’s Comments: The diagrams and radiographs included in the article help visualize the defects.