The Effect of Thermal Cycling on the Surface Roughness of Dental Casting Investments.
Abstract
Dental investments are a crucial and integral part of the lost wax method of casting. The investment material is the medium through which the wax replica of the restoration is transferred to the metal alloy. The surface of the original tooth preparation is transferred and reproduced without a significant alteration to the resultant metal restoration. The purpose of this study was to evaluate the surface roughness of six dental casting investments prior to and after the thermal cycling procedures used in the lost wax method of casting. The surface roughness of Type III gold alloys and ceramometal alloys, cast into the various dental investment samples, was also evaluated. Finally, the roughness average measurement method was evaluated for adaptability to dental casting investments. Ten epoxy resin dies were fabricated from the surface of six dental investment products after they were set against a smooth reference surface. Ten additional epoxy resin dies were fabricated from the six dental investment samples after they were set against the smooth reference surface and then thermal cycled at 1300 F for one hour. The surface roughness of these 120 epoxy resin dies were measured in microns with the profilometer. The next stage of the experiment involved casting Type III gold and ceramometal alloy against the six dental investment products and measuring the resultant surface roughness.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 1991
- Accession Number
- ADA239224
Entities
People
- Thomas F. Helbert
Organizations
- Air Force Institute of Technology