Abstract: In order to solve such problem that heating a mark such as a one-chip microprocessor which is easily damaged thermally in case of curing a heat-curing resin enclosing such one-chip microprocessor could have not been essentially made in event of embedding sealably such mark in the resin section of a denture, the present invention is characterized by that a groove-shaped recess for inserting the mark has previously been defined in a wax pattern indispensable for fabrication of the denture. For defining such recess, the implement for making a recess for embedding sealably the mark which is provided with a head shaped so as to have substantially the same dimension as that of the mark is used. More specifically, the head of the implement which has been heated by hot water is pressed upon a surface of the wax pattern to define such a groove-shaped recess as a result of melting a portion of the wax thus heated.