Ep. 680 - The Nuts and Bolts of Root Resorption and How to Treat It

Why do our own body's cells sometimes turn against our teeth, initiating a destructive process that can compromise even the most well-cared-for dentition? Root resorption represents one of the most challenging diagnostic and treatment scenarios in clinical dentistry.

Dr. Phil Klein, an endodontist with over 40 years of experience in dentistry, brings his extensive background in private practice, research and development, and dental education to this comprehensive discussion. Dr. Klein earned his DMD from the University of Pennsylvania School of Dental Medicine, completed his endodontic specialty training in 1985, and founded multiple dental companies including Dental Logics Inc. and Viva Learning LLC. He holds three dental patents and currently serves as Chairman of the Board for Viva Learning, the largest dental continuing education entity globally.

This episode provides a systematic approach to understanding the complex pathophysiology of root resorption, differentiating between inflammatory and non-inflammatory processes. Dr. Klein explains how clastic cell activation occurs through different mechanisms and emphasizes the critical role of tissue vitality in determining treatment outcomes. The discussion covers the fundamental requirements for each type of resorption, including the disruption of protective tissue barriers and the inflammatory responses that drive odontoclast activity.

Episode Highlights:

• Internal root resorption requires vital pulp tissue to remain active and will cease once complete pulp necrosis occurs, making non-surgical root canal therapy the treatment of choice when no perforation is present. Subclinical internal resorption occurs frequently in necrotic teeth as part of the normal pathophysiology of pulp death, detectable only through scanning electron microscopy.
• External inflammatory root resorption encompasses apical and lateral forms that both require necrotic pulp tissue and damaged precementum to initiate the resorptive process. Apical external inflammatory resorption is commonly present subclinically in cases of apical periodontitis, while lateral forms typically follow severe luxation injuries or avulsions.
• Pressure resorption represents a non-inflammatory external resorption caused primarily by orthodontic movement, misaligned tooth eruption, or slow-growing tumors. Since pulpal disease does not cause pressure resorption, endodontic therapy is not indicated in its management, and removing the causative agent will halt the process.
• External cervical resorption occurs at the cemento-enamel junction and requires damaged precementum combined with inflammation of the junctional epithelium rather than pulpal or periodontal ligament inflammation. This condition often presents idiopathically but can be associated with orthodontics, trauma, periodontal therapy, or internal bleaching with caustic agents.
• Replacement resorption or ankylosis represents the most severe form where bone replaces the periodontal ligament and progressively dissolves the tooth structure. Affected teeth lack physiologic mobility, produce a metallic tone when percussed, and show radiographic loss of periodontal ligament space, with decoronation advised when teeth reach one millimeter of infra-occlusion.

Perfect for: General dentists, endodontists, dental residents, and specialists who encounter resorptive lesions and need to differentiate between various types to develop appropriate treatment plans and prognoses.

Master the diagnostic criteria and treatment protocols that can mean the difference between saving a tooth and planning for extraction.