CBCT evaluation of unusual c-shaped root canal anatomy in lingually titled mandibular second premolars: a case report

Background: The root canal morphology of mandibular second premolars shows considerable anatomical variability, creating challenges during endodontic treatment. Among these variations, the C-shaped canal configuration is a rare but clinically significant anomaly that may be overlooked during routine diagnosis. Its occurrence in lingually tilted mandibular second premolars further complicates canal identification and treatment planning. Methods: This article reviews the incidence, classification, etiology, and clinical implications of C-shaped canals in mandibular second premolars through relevant literature and rare case reports. Diagnostic methods, including conventional radiography and cone-beam computed tomography (CBCT), were evaluated for their role in detecting complex canal anatomy. Results: C-shaped canals in mandibular second premolars were found to be uncommon but clinically important because of their complex morphology and variable presentation. Lingually tilted premolars posed additional challenges in access preparation and canal negotiation. Conventional radiographs often failed to provide sufficient diagnostic information, whereas CBCT offered accurate three-dimensional visualization of the canal configuration, enabling better diagnosis and treatment planning. Conclusion: C-shaped canal configurations in mandibular second premolars are rare anatomical variations that require careful evaluation for successful endodontic management. CBCT significantly enhances diagnostic accuracy and aids clinicians in identifying complex canal systems, particularly in lingually tilted premolar.