European Archives of Paediatric Dentistry

, Volume 15, Issue 5, pp 317–326 | Cite as

Root canal morphology of primary molars: a micro-computed tomography study

  • A. C. Fumes
  • M. D. Sousa-NetoEmail author
  • G. B. Leoni
  • M. A. Versiani
  • L. A. B. da Silva
  • R. A. B. da Silva
  • A. Consolaro
Original Scientific Article



This was to investigate the root canal morphology of primary molar teeth using micro-computed tomography.


Primary maxillary (n = 20) and mandibular (n = 20) molars were scanned at a resolution of 16.7 μm and analysed regarding the number, location, volume, area, structured model index (SMI), area, roundness, diameters, and length of canals, as well as the thickness of dentine in the apical third. Data were statistically compared by using paired-sample t test, independent sample t test, and one-way analysis of variance with significance level set as 5 %.


Overall, no statistical differences were found between the canals with respect to length, SMI, dentine thickness, area, roundness, and diameter (p > 0.05). A double canal system was observed in the mesial and mesio-buccal roots of the mandibular and maxillary molars, respectively. The thickness in the internal aspect of the roots was lower than in the external aspect. Cross-sectional evaluation of the roots in the apical third showed flat-shaped canals in the mandibular molars and ribbon- and oval-shaped canals in the maxillary molars.


External and internal anatomy of the primary first molars closely resemble the primary second molars. The reported data may help clinicians to obtain a thorough understanding of the morphological variations of root canals in primary molars to overcome problems related to shaping and cleaning procedures, allowing appropriate management strategies for root canal treatment.


Deciduous teeth Dental pulp cavity Micro-computed tomography Primary molars 


Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© European Academy of Paediatric Dentistry 2014

Authors and Affiliations

  • A. C. Fumes
    • 1
  • M. D. Sousa-Neto
    • 2
    • 3
    Email author
  • G. B. Leoni
    • 2
  • M. A. Versiani
    • 2
  • L. A. B. da Silva
    • 1
  • R. A. B. da Silva
    • 1
  • A. Consolaro
    • 1
  1. 1.Department of Pediatric Dentistry, Dental School of Ribeirão PretoUniversity of São PauloSão PauloBrazil
  2. 2.Department of Restorative Dentistry, Dental School of Ribeirão PretoUniversity of São PauloSão PauloBrazil
  3. 3.São PauloBrazil

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