Objective: To introduce a new prefabricated post-and-core system, a helical drilling bit and a prefabricated post-and-core consisting of a root canal orifice bur which was designed by the author.

• 摘要目的：介绍一种由螺旋型根管钻、行设计的根管口台阶状车针、成桩核组成的预成桩核系统。