Home Subscription Services
 
   

 
The International Journal of Prosthodontics
IJP Home Page
About the Editor
Editorial Board
Accepted Manuscripts
Submit
Author Guidelines
Submission Form
Reprints / Articles
Permissions
Advertising
MEDLINE Search
 
 
 
 
 
FacebookTwitterYouTube
Quintessence Publishing: Journals: IJP
The International Journal of Prosthodontics

Edited by George A. Zarb, BChD, DDS, MS, MS, FRCD(C)

ISSN 0893-2174

Publication:
May/June 1993
Volume 6 , Issue 3

Back
Share Abstract:

New High-Palladium Casting Alloys: Part 2. Effects of Heat Treatment and Burnout Temperature

Carr/Cai/Brantley/Mitchell

Pages: 233-241
PMID: 8397690

Castings simulating a maxillary central incisor coping were fabricated from five representative high-palladium alloys, using burnout temperatures of 1,400 degrees F and 1,500 degrees F, with a carbon-free phosphate-bonded investment. Three castings of each alloy were individually prepared at each burnout temperature. Each casting was sectioned into two specimens, and one specimen was subjected to simulated porcelain firing heat treatment. Polished and etched specimens in as-cast and heat-treated conditions were examined with optical and scanning electron microscopes. Mean values of Vickers hardness (1-kg load) were determined for each alloy and condition. It was observed that the simulated porcelain firing cycles caused major changes in as-cast bulk microstructures for the three first-generation alloys, while only subtle alterations were observed for the two second-generation alloys. In addition, complex regions associated with oxidation processes were found near the surfaces of all the heat-treated alloys. While the as-cast microstructure and the hardness of each alloy did not vary appreciably for the two burnout temperatures, the incidence of hot tearing in one first-generation alloy was substantially reduced at the lower burnout temperature. Statistically significant decreases in hardness generally occurred in the high-palladium alloys after the simulated porcelain firing cycles, but the relatively small changes (usually 10% or less) should not have any clinical significance. Other clinically relevant applications are also discussed.

Full Text PDF File | Order Article

 

 
Get Adobe Reader
Adobe Acrobat Reader is required to view PDF files. This is a free program available from the Adobe web site.
Follow the download directions on the Adobe web site to get your copy of Adobe Acrobat Reader.
  © 2014 Quintessence Publishing Co Inc
 

Home | Subscription Services | Books | Journals | Multimedia | Events | Blog
Terms of Use | Privacy Policy | About Us | Contact Us | Advertising | Help | Sitemap | Catalog