NS-14 "Filling" Lateral Canals: Evidence-based Insights from Biology

CE Hours: 1.5

Description: This presentation explores the biological relevance of filling lateral canals, grounded in histologic evidence and clinical observations. In the initial phase, the pulp's histological response to bacterial invasion is described. As bacteria colonize the necrotic tissue near the pulp chamber, an inflammatory response develops, while surrounding tissues remain uninflamed. Over time, with or without symptoms, necrosis progresses beyond the root canal orifices, and bacterial biofilms form along canal walls and anatomical complexities. When degeneration involves lateral canals, localized inflammation occurs, typically milder toward the periodontal ligament due to its rich blood supply. Eventually, biofilms may also form in these areas and, in some cases, extend beyond the root canal system, leading to extraradicular infections. The effectiveness of current cleaning protocols and modern devices in removing vital or necrotic tissue from lateral canals is critically evaluated through extensive histological studies on human specimens. It is shown that complete debridement is unachievable, and that forcing obturation materials into lateral canals does not equate to meaningful or effective filling. The discussion is supported by clinical cases and videos, offering a biologically and histologically informed perspective on whether filling lateral canals contributes to healing and long-term success.

Learning Objectives:  

• Describe the histological response of the pulp and periapical tissues to bacterial invasion, including the formation of biofilms within lateral canals.
• Evaluate the limitations of current endodontic techniques in cleaning and effectively filling lateral canals, based on histological evidence.
• Assess the clinical significance of lateral canal involvement in endodontic infections and healing outcomes, with a biologically informed perspective.