Micro-computed tomography evaluation of hard-tissue debris accumulation after root canal preparation with a single-file reciprocating system


  • Laila Gonzales Freire University of São Paulo
  • Elaine Faga Iglecias
  • Marcelo dos Santos
  • Giulio Gavini




X-Ray Microtomography, Root Canal Preparation, Smear Layer.


The aim of the present study was to evaluate and quantify the presence of hard-tissue debris inside curved canals, after root canal preparation with a single-fi le reciprocating system, with the aid of microcomputed tomography (micro-CT). Twenty-four mesial canals of mandibular molars were subjected to microtomographic scanning before and after preparation with R25 Reciproc instruments, using the SkyScan 1176 X-ray microtomograph, at a resolution of 17.42 µm. After reconstruction of the resulting images, co-registration was accomplished with DataViewer software. The CTAn and CTvol softwares were used for binarization of the objects of interest, volumetric analysis and 3D model reconstruction. Analysis of the micro-CT scans revealed debris accumulated inside the root canal, occupying an average 3.4% of the canal’s volume. It was concluded that micro-CT enabled identifying and quantifying the hard-tissue debris produced after instrumentation of mesial canals of mandibular molars with a single-fi le reciprocating system.


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Author Biography

Laila Gonzales Freire, University of São Paulo

Department of Dentistry


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Original Research