Molar–incisor malformation (MIM): a case report with a comprehensive review of the literature

Background: Molar–incisor malformation (MIM) is a recently described dental developmental anomaly involving the first permanent molars, maxillary central incisors, and second primary molars. Reported cases remain rare worldwide, with only sporadic reports from China and other Asian populations. The condition is characterized by abnormal root development and distinctive pulp chamber alterations, posing diagnostic and therapeutic challenges in pediatric dental practice. Case: We report a case of MIM in a Chinese child presenting with apical periodontitis of a maxillary central incisor. Clinical and radiographic examinations revealed characteristic cervical enamel defects and pulp chamber calcification consistent with MIM, along with genetic findings. Microscopy-assisted root canal treatment was performed, and radiographic follow-up at 9 months demonstrated resolution of apical inflammation and satisfactory clinical outcomes. In addition, a comprehensive review of the literature on MIM published since 2014 is presented. Conclusions: This case underscores the importance of early recognition of MIM and careful differential diagnosis to avoid mismanagement. Awareness of its characteristic clinical and radiographic features can facilitate appropriate treatment planning. Further case reports and genetic studies are warranted to elucidate the etiology and optimize management strategies for affected children.

Molar–incisor malformation; Dental developmental anomalies; Pulp calcification; Clinical management

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