ABSTRACT
Titanium is an inexpensive metal that can be used to create custom cast restorations. Although special investment and casting equipment is needed to make titanium castings, the potential benefit of inexpensive, biocompatible, and custom restorations is significant. Porcelain can easily be applied to titanium with excellent bond strength and esthetics. Problems associated with casting roughness and fit can be corrected using electrical discharge machining. A method of diagnosis and treatment planning that evaluates the restorative space prior to implant placement and eliminates the use of machined components is presented.
Subject(s)
Dental Implants, Single-Tooth , Dental Prosthesis Design/methods , Titanium , Biocompatible Materials , Costs and Cost Analysis , Crowns , Dental Bonding , Dental Casting Investment , Dental Casting Technique/instrumentation , Dental Porcelain , Denture, Partial, Temporary , Electrolysis , Esthetics, Dental , Humans , Metal Ceramic Alloys , Models, Dental , Patient Care Planning , Surface PropertiesABSTRACT
Traditional laboratory techniques are being supplemented by modern precision technologies to solve complex restorative problems. Electrical discharge machining combined with laser scanning and computer aided design-computer aided manufacturing can create very precise restorations without the lost wax method. A laser scanner is used to create a three-dimensional polyline data model that can then be converted into a stereolithography file format for output to a stereolithography apparatus or other rapid prototyping device. A stereolithography-generated model is used to create an electric discharge machining electrode via copper electroforming. This electrode is used to machine dental restorations from an ingot of titanium, bypassing the conventional lost wax casting process. Retaining screw access holes are machined using conventional drilling procedures, but could be accomplished with electric discharge machining if desired. Other rapid prototyping technologies are briefly discussed.
Subject(s)
Computer-Aided Design , Dental Polishing/methods , Dental Prosthesis Design , Dental Prosthesis, Implant-Supported , Titanium , Electrolysis , Image Processing, Computer-Assisted , Lasers , Models, DentalABSTRACT
The UCLA abutment was developed to create implant-retained restorations with ideal contours, excellent esthetics, and minimal vertical space requirements for restorative materials. A major drawback of this abutment is that casting inaccuracies in the lost-wax process are difficult to control. This article describes a method of refining cast implant-retained restorations by use of electrical discharge machining.
