[Dental alloys and allergy. Case report]

Area of Science:

• Dental Materials Science
• Allergology
• Biocompatibility Studies

Background:

• Cobalt-chromium-molybdenum (CoCrMo) alloys are widely used in removable partial dentures due to their reported biocompatibility and corrosion resistance.
• A 67-year-old woman had a history of successful, long-term use of a CoCrMo alloy denture framework.
• The patient underwent a molar tooth extraction, necessitating modification of the existing denture.

Observation:

• A nickel alloy retention was soldered to the CoCrMo denture framework after the extraction.
• Following the denture's reinsertion, the patient exhibited significant allergic reactions.
• Visual inspection revealed substantial corrosion at the soldered joint where the nickel alloy was attached.

Findings:

• The allergic reactions ceased completely after the removal of the nickel alloy retention and the corroded soldered joint.
• Despite the clinical resolution, an epicutaneous (patch) test indicated a positive reaction to cobalt.
• This case underscores that CoCrMo alloys possess inherent corrosion resistance and biocompatibility, which can be compromised by inadequate processing techniques.

Implications:

• The study supports the established high corrosion resistance and biocompatibility of CoCrMo alloys when processed correctly.
• Inadequate soldering techniques can lead to material degradation, loss of biocompatibility, and subsequent adverse patient reactions.
• The case emphasizes the importance of precise diagnostic criteria for allergic reactions, distinguishing them from less specific adverse responses to medical devices.