Microscopic removal of type III dens invaginatus and preparation of apical barrier with mineral trioxide aggregate in a maxillary lateral incisor: A case report and review of literature

BACKGROUND: Invaginated teeth pose greater challenges in clinical management because of their complex configuration. With advancements in equipment and materials, such as the dental operation microscope, cone-beam computed tomography and mineral trioxide aggregate, the preservation rate of type III dens invaginatus could be greatly increased. CASE SUMMARY: This case report presented a 31-year-old woman with complaints of spontaneous swelling and pain in the right maxillary lateral tooth. With the aid of cone-beam computed tomography, type III dens invaginatus with apical periodontitis was diagnosed and confirmed. Three-visit endodontic treatment was performed. In the first visit, the invagination was carefully removed under the dental operation microscope, and chemomechanical preparation was done. In the second visit, mineral trioxide aggregate apical barrier surgery was performed in this tooth. In the third visit, the canal was finally obturated with thermoplastic gutta-percha to recover the crown morphology. A 26-mo follow-up revealed a satisfied outcome both in the radiographic and oral examinations. CONCLUSION: In this case, removal of the entire abnormal structure provided great convenience for the follow-up treatment. When confronted with the same clinical case in the future, we can take a similar approach to address it.