case report (RESIDENTS CORNER)
Nonsurgical retreatment of a maxillary first molar with three mesiobuccal canals, C-shaped distobuccal-palatal morphology, and iatrogenic perforation repair using image-guided visualization: A case report
Arvin Alexander¹, Theodore D. Ravenel¹*, Brian Bergeron ¹
https://doi.org/10.71347/pv59me60
¹ Dental College of Georgia at Augusta University, 1430 John Wesley Gilbert Drive, Augusta, GA 30912, USA
*Corresponding author:
Theodore Ravenel, DMD
Dental College of Georgia at Augusta University
Augusta, GA, USA
E-mail: travenel@augusta.edu
Conflict of Interest:
The authors declare no conflicts of interest related to this case report.
Acknowledgments:
The authors report no acknowledgments.
Abstract
Background: The root canal anatomy of maxillary molars can be highly variable, with fused roots, C-shaped canal configurations, and supernumerary canals presenting significant clinical challenges. The presence of three mesiobuccal canals (MB3) is an exceptionally rare anatomical variation that has been reported infrequently in maxillary first molars.
Case description: A 50-year-old Chinese male was referred for evaluation of the maxillary right first molar (tooth #3), which had undergone previous root canal treatment and restoration with a zirconia crown two years earlier. Clinical examination revealed a draining sinus tract approximating the mesiobuccal root. Cone beam computed tomography (CBCT) demonstrated an untreated mesiobuccal root containing three canals (MB1, MB2, and MB3), a C-shaped configuration connecting the distobuccal and palatal canals, an overfilled palatal canal, a poorly obturated distobuccal canal, and a suspected iatrogenic perforation of the pulpal floor. Nonsurgical retreatment was completed in two visits utilizing image-guidance with the Zumax DentSight AR integrated visualization system, and a surgical operating microscope to identify and manage the complex canal anatomy.
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