J Adv Prosthodont.  2014 Apr;6(2):138-145. 10.4047/jap.2014.6.2.138.

Physico-mechanical properties and prosthodontic applications of Co-Cr dental alloys: a review of the literature

• Al Jabbari YS

• KMID: 2233343
• DOI: http://doi.org/10.4047/jap.2014.6.2.138

Abstract

Cobalt-Chromium (Co-Cr) alloys are classified as predominantly base-metal alloys and are widely known for their biomedical applications in the orthopedic and dental fields. In dentistry, Co-Cr alloys are commonly used for the fabrication of metallic frameworks of removable partial dentures and recently have been used as metallic substructures for the fabrication of porcelain-fused-to-metal restorations and implant frameworks. The increased worldwide interest in utilizing Co-Cr alloys for dental applications is related to their low cost and adequate physico-mechanical properties. Additionally, among base-metal alloys, Co-Cr alloys are used more frequently in many countries to replace Nickel-Chromium (Ni-Cr) alloys. This is mainly due to the increased concern regarding the toxic effects of Ni on the human body when alloys containing Ni are exposed to the oral cavity. This review article describes dental applications, metallurgical characterization, and physico-mechanical properties of Co-Cr alloys and also addresses their clinical and laboratory behavior in relation to those properties.

Keyword

Co-Cr alloys; Base metal alloys; Physical properties; Mechanical properties; Metallurgical characterization

MeSH Terms

Alloys
Dental Alloys*
Dentistry
Denture, Partial, Removable
Human Body
Mouth
Orthopedics
Prosthodontics*
Alloys
Dental Alloys

Figure

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  Fig. 1 Backscattered electron images (BEI) from the surface of a Co-Cr alloy manufactured by conventional casting (A) and selective laser melting (SLM) techniques (B). A second Mo-rich phase (white areas/black arrows) occupies the interdendritic spaces in the cast alloy. A homogeneous single-phase microstructure is shown for the Co-Cr alloy manufactured by the SLM technique.

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  Fig. 2 Surface and subsurface interdendritic porosity formed during solidification of a Co-Cr-based alloy. (A) Secondary Electron Image and (B) Backscattered electron image. It is readily shown in the BEI that the pores follow the shape and distribution of the white Mo-rich phase.

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  Fig. 3 Secondary Electron Image (SEI) of a fractured surface of an RPD lingual bar major connector made from a cast Co-Cr alloy. It shows extensive and coarse dentritic structure.

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