Index pin and die spacer combination for dental model

Abstract

Method and apparatus for preparing a wax replica of a dental prosthesis is disclosed. The method of the invention is carried out by preparing a composite dental model which includes a base portion, an odontal die projecting from the base portion having a cavity in which the dental prosthesis is to be implanted, and an index pin embedded within the composite dental model. A complementary dental model having an odontal projection defining an occlusal surface for engaging the odontal die is also prepared. The index pin includes an anchor shank portion embedded within the odontal die, an alignment shank portion embedded in the base portion and a radially projecting collar portion disposed in the interface of the base portion and the odontal die. The odontal die and embedded index pin are removed from the base portion of the composite dental model and a die spacer is placed around the alignment shank portion of the index pin. After the odontal die together with the die spacer and index pin are reinserted into the base portion of the composite model, a quantity of wax is deposited into the odontal die cavity. The wax deposit is compressed by bringing the occlusal surface of the complementary model into engagement with the occlusal surface of the composite model. The die spacer produces dimensional compensation for the expansion of a gold alloy casting when the wax deposit is used in a conventional investment casting procedure.

Dependencies are inferred from the claim text.