Three-dimensional reconstruction: A new method for the evaluation of apical microleakage

The purpose of this study was the evaluation of a new method for studying a pical microleakage by using a three-dimensional (3-D) reconstruction method . Fourteen human single-rooted mandibular teeth were used for this work. Th e canals were prepared with hand instruments by using the step-back techniq ue. To supply a focus to the study of the method, the teeth were divided in to two groups that were obturated using two different sealers. India ink wa s used for passive stain. Serial cross-sections 0.75 mm thick were taken fr om each specimen by using a special microtome. Each section was photographe d under a stereoscopic microscope, Each photograph was digitized and proces sed to obtain a 3-D reconstruction of the external surface of the teeth, th eir corresponding prepared root canals, and their apical microleakage. Samp le size and experimental methods were not designed to make valid groups; ho wever, apical microleakage was observed in both groups ranging between 2.25 to 8.25 mm height. The 3-D reconstruction method has proved to be a useful tool in the study of apical microleakage.