A computerized method for the evaluation of root canal morphology

The objective of this research was to develop a technique that would allow three-dimensional imaging of root canals utilizing computer image processing. Ten single-rooted permanent human teeth with mature apices were analysed. The teeth were decoronated and fixed on boards with the long axis of the root perpendicular to the board. The cross-sectioning started at the root apex and continued in the coronal direction, roughly perpendicular to the long axis of the root. The samples were divided into two groups. The first five samples were sectioned 15 times, each section being 0.5-mm thick, in order to obtain the three-dimensional reconstruction of the root and the root canal. The second group of five samples served for the graphical reconstruction of the apical portion of the root canal. The root apex of each sample was cross-sectioned 19 times and each section was 0.2-mm thick. After each section, the root canal contour was defined utilizing the calibrated net with coordinate system in the ocular of the stereomicroscope. The coordinates of the root canal cross-section contour thus determined, together with the value of the thickness of each cut, were relevant input data for the reconstruction of the root canal cross-sections, longitudinal sections and for the final three-dimensional rebuild of the root and the root canal model. This technique appears to be highly accurate in determining the anatomy of the root canal system and may also be applied in other fields of dental research.