Bio-Obturation for Internal Root Resorption in Contralateral Mandibular Molars: A Five-Year Case Study

Internal root resorption (IRR) is a rare but complex condition characterized by progressive destruction of the internal dentin walls, typically resulting from chronic pulp inflammation, trauma, or infection. Managing apical IRR, particularly in teeth with extensive apical lesions, presents significant challenges due to the limitations of traditional root canal treatment (RCT) and obturation techniques. This report discusses the nonsurgical management of two contralateral mandibular first molars in a 49-year-old male patient, both exhibiting apical IRR and large endodontic lesions. Despite the previous RCT, the teeth continued to show clinical symptoms and radiographic evidence of persistent apical lesions and resorptive defects. The patient elected nonsurgical retreatment with bio-obturation using endodontic biomaterials. After cleaning, disinfecting, and preparing the root canals, the teeth were obturated with a calcium-enriched mixture cement. Within one week, the patient's symptoms resolved, and a radiographic follow-up at five years revealed complete healing of the apical lesions. This case underscores the effectiveness of bio-obturation using endodontic biomaterials in treating apical IRR with large lesions, providing a nonsurgical solution that preserves natural tooth structure, promotes healing, and minimizes the risk of reinfection. Bio-obturation with endodontic biomaterials should be considered a viable treatment option for IRR, especially in cases with extensive apical lesions, and further studies are warranted to evaluate its long-term efficacy in more complex cases.