Which are the main features of Chrome – Cobalt alloys, and why are they so important for prosthodontist laboratories? Discover how to use them, thanks to the suggestions we’ve got from recent studies and from the prosthodontists of Mesa Italia who have tested them.
- High stiffness
The high elasticity of Cr/Co alloys offer a high stiffness for the intraoral use, without needing voluminous sections and reducing the weight and the space of the metal structure. - Strength
High specific strenght, due to the crystallographyc nature of Cobalt, to the recinforcing effect of Chrome and of the other elements that can be found in the solid solution. - Corrosion resistance
This requirement, necessary for a good tolerability of the prosthetic restauration, is by now confirmed by different studies and from the prosthodontist societies. - Wear resistance
- Less density compared to gold alloys
Reduction of the weight of the prothesis. - Lack of magnetic properties
- Affordability
The features listed on top1,2,3, make Co-Cr alloy “special” , as it presents a limited number of cons:
- Thicker and darker oxide layers
A longer oxidation process, could cause a insufficient bond among the metal and ceramic, and create the release of Chrome Ion with possible toxic effect. - Hardness
Reason why milling and finishing are more difficult. - Higher melting point
Between 1350-1450°, means more difficulties during manufacturing
These are limits that in a prosthodontist laboratory we can simply exceed, making the Chrome Cobalt alloys a precious ally for the dental sector professionals. In a new article we explain you how to solve the few cons of this alloy.
Bibliography
- Mohamed A. Naser Al Aqueleli Wear Characteristics of Metallic Biomaterials: A Review Materials 2015 May; 8(5): 2749–2768
- Youssef S. Al Jabbari Physico-mechanical properties and prosthodontic applications of Co-Cr dental alloys: a review of the literature J Adv Proshodont 2014; 6:138-45
- Gulmez, Tarcin Mechanical Properties of CAD/CAM Manufactured and Prefabricated Endodontic Posts Key Engineering Materials Vols 493-494 (2012) pp 649-654