tooth resorption tooth resorption resorption of the root of the tooth, or root resorption, is the progressive loss of dentin and cementum by the action of odontoclasts. root resorption is a normal physiological process that occurs in the exfoliation of the primary dentition. however, pathological root resorption occurs in the permanent or secondary dentition and sometimes in the primary dentition. root resorptionpost traumatic external tooth resorption 9specialtydentistrysymptomsdark tooth discoloration, swollen gums, chip toothcomplicationstooth loss, infectiontypesexternal (most common), internalcausestrauma, idiopathicrisk factorstrauma, orthodonticsdiagnostic methoddental examination, x-raystreatmentdental crowns, tooth extraction, gum surgery causes while resorption of bone is a normal physiological response to stimuli throughout the body, root resorption in permanent dentition and sometimes in the primary dentition is pathological. the root is protected internally (endodontium) by pre-dentin and externally on the root surface by cementum and the periodontal ligament. chronic stimuli that damage these protective layers expose underlying dentin to the action of osteoclasts. root resorption most commonly occurs due to inflammation caused by pulp necrosis, trauma, periodontal treatment, orthodontic tooth movement and tooth whitening. less common causes include pressure from malpositioned ectopic teeth, cysts, and tumors. pathophysiology x-ray of affected tooth (incisor 9, left).