Abstract
The root suface debridement was recognized as the most important part of periodontal therapy, but root surface shapes were still unclear. The purpose of this study was to show how to clarify root surface shapes; bilateral maxillary and mandible teeth were used, some of which could not be cut. For these a plaster replica was made. The teeth were embedded polyacrylics and they were in cross section every 1 mm at right angle to the axis of the root. Sections were traced using a 10. Nikon projector; this trace was input to a computer and a program built up a three-dimensional display of the roots. This threedimensional display can show the direction and cutting surface in any desired color. It is able to show average root surface shapes because many teeth were analyzed. This analysis system will provide a greater anatomical knowledge of roots for the periodontal practitioner.
