A COMPUTERIZED METHOD FOR THE EVALUATION OF ROOT-CANAL MORPHOLOGY

The objective of this research was to develop a technique that would a llow three-dimensional imaging of root canals utilizing computer image processing. Ten single-rooted permanent human teeth with mature apice s were analysed. The teeth were decoronated and fixed on boards with t he long axis of the root perpendicular to the board. The cross-section ing started at the root apex and continued in the coronal direction, r oughly perpendicular to the long axis of the root. The samples were di vided into two groups. The first five samples were sectioned 15 times, each section being 0.5-mm thick, in order to obtain the three-dimensi onal reconstruction of the root and the root canal. The second group o f five samples served for the graphical reconstruction of the apical p ortion of the root canal. The root apex of each sample was cross-secti oned 19 times and each section was 0.2-mm thick. After each section, t he root canal contour was defined utilizing the calibrated net with co ordinate system in the ocular of the stereomicroscope. The coordinates of the root canal cross-section contour thus determined, together wit h the value of the thickness of each cut, were relevant input data for the reconstruction of the root canal cross-sections, longitudinal sec tions and for the final three-dimensional rebuild of the root and the root canal model. This technique appears to be highly accurate in dete rmining the anatomy of the root canal system and may also be applied i n other fields of dental research.