The imaging of root canal obturation using micro-CT.
OBJECTIVE
To examine the potential and accuracy of micro-computed tomography (micro-CT) for imaging of filled root canals.


METHODS
The root canals of five extracted maxillary teeth were shaped manually with K-files. After irrigation and drying, the root canals were filled by lateral condensation using gutta-percha cones and AH plus (Dentsply Maillefer, Ballaigues, Switzerland) as sealer. The filled root canals were examined by micro-CT at resolutions <11 microm. Three-dimensional reconstructions of the root canal fillings were made. The roots were sectioned histologically and standard photographs of the sectioned surfaces were taken. Digitized photographic images and the corresponding micro-CT sections were correlated qualitatively by superimposition. Quantitative morphometric data were obtained with respect to the surface area of the root canal filling and the individual gutta-percha points of the histological and the micro-CT sections. Pearson correlation coefficients were calculated.


RESULTS
There was a good qualitative correlation between the images from the histological and the micro-CT sections. The fillings were clearly differentiated from the root canal walls. Individual gutta-percha cones and sealer were discernable. Pearson correlation coefficients showed a highly significant correlation between the two methods (P < 0.001) with respect to the area of the complete root canal filling (r = 0.992) and the gutta-percha cones (r = 0.968).


CONCLUSIONS
The micro-CT technique was a highly accurate and nondestructive method for the evaluation of root canal fillings and its constituents. Qualitative and quantitative correlation between histological and micro-CT examination of root canal fillings was high.
Jung
M
M
Polyclinic for Operative and Preventive Dentistry, Faculty of Dentistry, Justus-Liebig-University, Giessen, Germany. martin.jung@dentist.med.uni-giessen.de
Lommel
D
D
Klimek
J
J
D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging*; D004853:Epoxy Resins; D006171:Gutta-Percha; D006801:Humans; D021621:Imaging, Three-Dimensional; D008953:Models, Anatomic; D003765:Models, Dental; D015203:Reproducibility of Results; D012387:Root Canal Filling Materials; D012389:Root Canal Obturation; D014057:Tomography, X-Ray Computed / Q000379:methods*
D004853:Epoxy Resins; D012387:Root Canal Filling Materials; C534916:epoxy resin-based root canal sealer; D006171:Gutta-Percha