Abstract: A mold assembly and sprue configuration for dental investment casting includes a ring shaped casing, a base and a cover all made of resilient plastic material and fictionally engaged with each other. The base includes a raised neck having a top surface with a sighting bead for use in mounting wax forms on the sprue, positioned within the casing. The sprue includes a post for engaging a blind bore in a hub of the base. The cover includes a downwardly extending plug which extends into the body of the casing, and a curved lip with recess for facilitating the pouring of investment solution into the mold. The sprue has three spokes and a ring which are all triangular in cross-section to reduce the amount of metal needed in the precision casting to be made with the invention and also to provide a convenient flat upper surface for mounting wax forms to the sprue.

Abstract: A method of investment casting a dental restoration and a dental restoration made, thereby and a pattern therefor, include, in the preferred embodiment thereof, the forming of a wax pattern that includes at least two wax retainers interconnected by a wax link that includes a separable link made of a preformed wax pair of blades with confronting parallel identically shaped surfaces in prepositioned intimate contact. The link is preferably set into a slot of the same thickness as the link cut into the connector of the pattern as the retainers are mounted on precisely positioned models of tooth abutments, and waxed to the connector faces exposed by the cut. The link is then separated to divide the pattern into two components from which corresponding sections of the restoration are cast by the lost wax investment casting method. The cast sections so formed have weldable faces thereon corresponding to the interface surfaces of the link blade of the pattern components.

Abstract: A mold assembly and sprue configuration for dental investment casting includes a ring shaped casing, a base and a cover all made of resilient plastic material and fictionally engaged with each other. The base includes a raised neck having a top surface with a sighting bead for use in mounting wax forms on the sprue, positioned within the casing. The sprue includes a post for engaging a blind bore in a hub of the base. The cover includes a downwardly extending plug which extends into the body of the casing, and a curved lip with recess for facilitating the pouring of investment solution into the mold. The sprue has three spokes and a ring which are all triangular in cross-section to reduce the amount of metal needed in the precision casting to be made with the invention and also to provide a convenient flat upper surface for mounting wax forms to the sprue.

Abstract: An apparatus for gripping hot investment molds either of the ring type or of the oval type, has a plastic handle with an elongated square tube extending therefrom. A trigger in the handle is connected to a linkage rod which pulls back on a closer frame. Rearwardly extending crossed tails of a pair of jaws are squeezed together by rearward movement of the closer, for closing outwardly extending palms of the jaws around an investment mold. The jaw assembly is removable so that jaws having shapes adapted specifically to engage either an investment ring or an investment oval can be provided.

Abstract: A cap for an investment vessel for receiving investment material comprises a platform having a contoured edge and an underside. A wedge is located on the underside of the platform and is frictionally engageable with at least a portion of an inner edge of the top of the vessel. When the cap is placed in frictional engagement with the vessel, the contoured edge provides a restricted opening to the vessel for controlling the flow of the investment material. A lip is provided on the platform at the contoured edge for channeling investment material to the opening.

Abstract: A device for receiving dental investment solution to create an investment mold, has an oval casing which fictionally engages an oval base. Anti-rotation tabs of the base extend into anti-rotation slots in the casing, with both casing and base made of flexible plastic material.

Abstract: An adjustable investment mold positioner includes a resilient band bent into a partial cylinder. Opposite ends of the band bound an opening at the side of the cylinder. A mold receiving member made of bent metal has side walls with bent connectors that are attached to the opposite ends of the band. A recess is formed between the side walls for receiving an oval investment mold. The outer cylindrical configuration of the positioner is readily engageable within the cradle of a conventional casting machine which is designed for normally receiving cylindrical investment molds. In this way, oval investment molds can be received in a secure manner within the conventional casting machines.

Abstract: Handle is formed with the metal portion of a dental prosthesis so that the handle can be used for supporting and handling the metal structure from the mold to the final finishing, when the handle is cut off. The handle preferably has both a ring for supporting the structure on a post and a ball for grasping of the metal structure.

Abstract: Gate is a wax structure for forming part of a wax master in investment casting of a dental prosthesis. The gate has a square feeder with a circular disc on each end. The square feeder reduces the cracking stresses between adjacent feeders to reduce unwanted fins, and the square shape aids in final cutoff of the cast prosthetic. In the wax master, one of the discs is secured to the prosthetic form and the other disc to the conventional reservoir bar. The disc shape aids in filleting to the form and bar.

Abstract: Prosthesis substructure for ceramic coating is configured for reduced metallic body volume, increased vertical loading strength and increased surface bonding area for ceramic bond. This is accomplished by configuring the substructure with generally triangular truss configuration.

Abstract: The wax master sprue and runner or gate form used in the investment casting process of dental prostheses has a web between the runners or gates so that the runners or gates are secured together to prevent shifting of the runners or gates during the molding of the casting material around the wax master.

Abstract: Dental thickness gauge is for gauging the space between a cusp and fossa during preparation for a restoration. The dental thickness gauge is a plurality of tabs in a set, with each tab being of a different thickness. The material of the tabs is tough and flexible.