Evaluation of the internal anatomy of paramolar tubercles using cone-beam computed tomography

  • G. ColakogluEmail author
  • I. Kaya Buyukbayram
  • M. A. Elcin
  • M. Kazak
  • H. Sezer
Original Article



To evaluate the internal anatomy of paramolar tubercles (PTs) on molars, determine the existence of root canals in these structures that either communicate with or are isolated from the main root canals of teeth, and analyze the prevalence of root fusion and a C-shaped canal configuration using cone-beam computed tomography (CBCT).

Materials and methods

Twenty-six molars with PTs from the study group and 664 molars without PTs from the control group were evaluated using CBCT. The locations and sizes of tubercles were noted. The existence of root canals in PTs was detected. All teeth were evaluated according to the presence or absence of root fusion and a C-shaped canal configuration. Statistical analyses were performed with Pearson Chi square and Fisher’s exact tests (p < 0.05).


Eleven (42.3%) PTs with their own canals communicated with the main root canals of teeth, and 10 of 11 PTs (90.9%) were larger than 4 mm in size. No PT possessed its own canal independent from the other canals. Teeth with PTs tended to have more root fusions than teeth without PTs. A statistically significant correlation was observed between PTs and the C-shaped canal configuration (p < 0.01). Maxillary second molars with PTs were the major teeth showing variations in the internal morphology.


PTs are an uncommon anatomical variation that is specific to the coronal and radicular morphology. Therefore, clinicians should be aware of its unpredictable and complex internal anatomy, particularly in cases requiring endodontic treatment. CBCT is recommended for teeth with PTs, particularly maxillary second molars, to improve the prognosis of the teeth.


Paramolar tubercle C-shaped canal configuration Root fusion Cone-beam computed tomography 



All authors disclose no actual or potential conflicts of interest, including any financial, personal, or other relationship with other people or organizations that could inappropriately influence this work.

Author Contributions

GC: Planning of the study, evaluation of CBCT images, writing of the study. IKB: Planning of the study, evaluation of CBCT images, language editing. MAE: Evaluation of CBCT images, language editing. MK: Planning of the study, language editing. HS: Statistical analysis.


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Copyright information

© Springer-Verlag France SAS, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Oral and Maxillofacial Radiology, Faculty of DentistryIstanbul Aydin UniversityIstanbulTurkey
  2. 2.Department of Endodontics, Faculty of DentistryIstanbul Aydin UniversityIstanbulTurkey
  3. 3.Department of Restorative Dentistry, School of Dental MedicineBahcesehir UniversityIstanbulTurkey
  4. 4.Department of Biostatistics, Faculty of MedicineIstanbul Aydin UniversityIstanbulTurkey

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