Root canal morphology of hypomineralised first permanent molars using micro-CT

  • C. NebodaEmail author
  • R. P. Anthonappa
  • D. Engineer
  • N. M. King
  • P. V. Abbott
Original Scientific Article



To investigate the root canal morphology of hypomineralised first permanent molars (FPMs) using micro-CT (μCT).


Twenty-four hypomineralised FPMs and five clinically sound FPMs were scanned using μCT and assessed using the following parameters: (i) root canal configuration, (ii) connecting canal frequency, (iii) enamel, dentin, and pulp volumes, (iv) cusp tip to pulp horn distance, root canal length, root canal width, and dentin thickness, and (v) the influence of the root canal system landmarks on access cavity outline forms and canal curvature. A two-way repeated-measures analysis of variance was employed with the statistical significance set at p < 0.05.


The frequency of accessory and connecting canals was higher in hypomineralised FPMs. Mesio-buccal cusp horn was found to be the closest to its corresponding cusp tip in both groups. There was no significant difference between the root lengths, dentine widths, and pulp space measurements of hypomineralised FPMs compared to clinically sound FPMs. The best angulation to access FPMs was straight-line radicular, along the pulp horn.


This study illustrates some variations in the root canal morphology in hypomineralised FPMs compared to clinically sound FPMs. Future studies should focus on assessing these parameters in larger samples.


First permanent molars Micro-CT Molar incisor Hypomineralisation Molar hypomineralisation Root canal morphology 



The authors acknowledge the facilities, and the scientific and technical assistance of the National Imaging Facility at the Centre for Microscopy, Characterisation and Analysis, and University of Western Australia, a facility funded by the University, State and Commonwealth Governments. The authors would also wish to sincerely thank the Australian Dental Research Foundation (Ref: 36-2016) for its financial support of this research.


This study was funded by Australian Dental Research Fund (36-2016).

Compliance with ethical standard

Conflict of interest

Authors declare no conflicts of interest.

Ethical approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee (University of Western Australia Human Research Ethics Committee—RA/4/1/7973) and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.


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Copyright information

© European Academy of Paediatric Dentistry 2019

Authors and Affiliations

  1. 1.Discipline of Paediatric Dentistry, School of DentistryThe University of Western AustraliaNedlandsAustralia
  2. 2.The Centre for Microscopy, Characterisation and AnalysisThe University of Western AustraliaNedlandsAustralia

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