Biomechanical preparation in primary molars using manual and three NiTi instruments: a cone-beam-computed tomographic in vitro study

  • A. MankerEmail author
  • M. Solanki
  • A. Tripathi
  • M. L. Jain
Original Scientific Article



To evaluate nickel–titanium rotary systems, ProTaper Universal (PTU), ProTaper Next (PTN), self-adjusting file (SAF), and stainless steel hand K files in deciduous root canals in longitudinal and horizontal sections by three-dimensional reconstruction. Whether there was any difference in shaping ability, transportation, dentine removal, untouched canal surface area, and preparation time among the different groups when used in primary root canals.


Shaping and cleaning of canals in primary molars were done using the four systems, and CBCT and specialized software were used for scanning, image processing, three-dimensional reconstruction, and analysis of pre-operative and post-operative to evaluate the groups for their shaping properties, transportation, amount of dentine removal, untouched canal surface area, and preparation time in primary root canals.


None of the groups reported stripping of canals or instrument failure. SAF demonstrated less removal of dentine as compared to other groups. Hand K files presented with high untouched canal surface area, while it was least with SAF. In addition, rotary files provided faster preparation than hand files, and among the rotary systems, PTN took least time for cleaning and shaping of canals. All the groups were similar in transportation at cervical and apical third.


Under the conditions of this study, SAF seemed to result in more conservative and meticulous removal of dentine. This is desirable to preserve the integrity of thin-walled primary root canals. SAF also showed less untouched canal areas suggesting better contact with the primary canal walls. The rotary file groups required less clinical time which is important in paediatric treatments.


Rotary and manual files in deciduous Three-dimensional reconstruction analysis Untouched canal surface areas Amount of dentine removed Preparation time 



Our sincere gratitude to Dr. Vinay Kumar Kulkarni, Dr. Divya S Sharma, Dr. Alkesh Godhane and Oracle CBCT Centre for their constant support throughout the study.

Author contributions

AM and MS conceived the idea, conducted the study, and penned down the manuscript. MS guided and provided necessary training for the study. AT helped in experimentation during three-dimensional evaluation with ImageJ software, sample collection, and editing of the manuscript. MLJ provided guidance in understanding and operating the MIMICS software.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© European Academy of Paediatric Dentistry 2019

Authors and Affiliations

  1. 1.Department of Pedodontics and Preventive DentistrySri Aurobindo College of Dentistry, SAIMSIndoreIndia
  2. 2.Department of Pedodontics and Preventive DentistryModern Dental College and Research CentreIndoreIndia
  3. 3.Department of Orthodontics and Dentofacial OrthopaedicsSri Aurobindo College of Dentistry, SAIMSIndoreIndia
  4. 4.Department of Mechanical EngineeringSGS Institute of Technology and ScienceIndoreIndia

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