Abstract
The rebuilding abutment teeth with the metal core is one of the most important procedures for the long-termmaintenance of the teeth which are due to treated with the crown prosthesis. Hitherto, dental cement, dental amalgam, metal casting, and the combined method with the readymade post and composite resin have been applied generally for the rebuilding abutment teeth. The rebuilding abutment teeth with the metal casting has been widely applied for a long time and had a good reputation clinically, while it has been improved for the clinical use. But, this method brings difficulties when applied for the divergent and multi-rooted teeth. Therefore, the split method has been used for the divergent and multirooted teeth, since it is difficult to insert the one piece casting dowel-core into the non-parallel root canals. Althougt this difficulty is originated from the divergence in the direction of the root canals, some techniques such as the application of carbon rods and of the investment materials have been designed to remove this problem. But, these method has not been accepted for the difficulty in the laboratory technique. This study was performed to improve the defects of these previous techniques. The results showed that the relatively precise fitness between the ready-made post and the post channels can be obtained by using the carbon rods, and that the combined technique with ready-made screw post can accomplished the primary object of this study.
