CBCT-guided nonsurgical endodontic treatment of molar-incisor malformation: a 4- to 6-year follow-up case series in pediatric patients

Background: Molar-Incisor Malformation (MIM) is a recently identified developmental dental anomaly. It is characterized by normal crown morphology, but exhibits short, morphologically altered roots, predominantly affecting the permanent first molars and occasionally the incisors. Because MIM results in a complex internal anatomy and calcified canal structures, standardized treatment protocols have not yet been established, and extraction is often recommended. This case series reports successful nonsurgical endodontic management of MIM-affected molars with long-term follow-up aided by cone-beam computed tomography (CBCT). Cases: Three pediatric patients diagnosed with MIM in their first permanent molars underwent cone-beam computed tomography-guided nonsurgical endodontic treatment. Case 1 presented with a fused root and an immature palatal apex. This case required revascularization of the palatal root, whereas the remaining canals were treated nonsurgically. Case 2 had six distinct canals in the maxillary first molar. All the canals identified using CBCT were successfully treated. Case 3 involved a left mandibular first molar with five canals, including a mid-mesial canal. This case was managed with nonsurgical root canal treatment despite the patient’s limited cooperation. Across all cases, CBCT enabled accurate identification of canal morphology, detection of additional and calcified canals, and formulation of appropriate treatment strategies based on anatomical characteristics. Conclusion: Despite the severely compromised root anatomy, CBCT-supported nonsurgical endodontic treatment enabled successful long-term preservation of MIM-affected molars. All cases maintained stable clinical and radiographic status throughout the extended follow-up period. CBCT serves as a critical diagnostic adjunct, providing a precise three-dimensional assessment of complex canal configurations to guide treatment decisions. With careful case selection, nonsurgical endodontic management is a conservative and viable alternative to extraction. This approach is particularly valuable for pediatric patients in whom dental preservation is required until craniofacial growth is completed.

Molar-incisor malformation; Cone-beam computed tomography; Endodontic treatment; Root malformation; Pediatric dentistry

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