Oral Galvanism Side Effects: Comparing Alloy Ions and Galvanic Current Effects on the Mucosa-like Model

Area of Science:

• Biomaterials Science
• Oral Medicine
• Toxicology

Background:

• Oral galvanism, arising from dental alloys, can lead to adverse effects like burning sensations and inflammation.
• The exact mechanisms behind oral galvanism-related side effects remain unclear, with direct current and alloy corrosion ions being suspected contributors.

Purpose of the Study:

• To systematically compare the damaging effects of galvanism (direct current + corrosion ions), direct current alone, and corrosion ions alone.
• To identify the key factors responsible for side effects of dental alloys using an in vitro model.

Main Methods:

• Utilized an in vitro mucosa-like model using immortalized human keratinocytes (HaCaTs).
• Compared the high-risk dental alloys Ti64-AgPd and NiCr-AgPd.
• Assessed the effects of synergistic galvanism, direct current, and corrosion ions separately.

Main Results:

• Galvanic current emerged as the primary damaging factor in cytotoxic processes related to galvanic coupling of intraoral appliances, particularly in the short term (28 days).
• The contribution of corrosion ions, specifically Ni2+, to synergistic toxicity was demonstrated.
• Corrosion ions may pose a significant danger in the long term.

Conclusions:

• Galvanic current is likely the leading cause of short-term cytotoxic effects from dental alloy interactions in the oral environment.
• Corrosion ions, such as Ni2+, play a role in the combined toxicity and could be a significant long-term risk factor.
• Understanding these factors is crucial for mitigating side effects associated with dental alloys.