Biologic assessment of copper-containing amalgams

Area of Science:

• Dental Materials Science
• Biocompatibility Studies
• Restorative Dentistry

Background:

• New high-copper dental amalgam alloys aim to reduce creep and prevent marginal fractures in restorations.
• Conventional silver/tin alloys and zinc oxide eugenol cement serve as benchmarks for material performance.

Purpose of the Study:

• To evaluate the biocompatibility and potential adverse effects of high-copper dental amalgam alloys.
• To compare the pulp response to high-copper alloys versus conventional materials in vivo.

Main Methods:

• High-copper amalgam fillings were placed in cavities in deciduous monkey teeth.
• Specimens were also implanted subcutaneously in rats within polyethylene tubes.
• Conventional silver/tin alloys and zinc oxide eugenol cement were used as controls.

Main Results:

• High-copper alloys induced more severe pulp damage compared to conventional materials.
• A significant number of high-copper alloy specimens were exfoliated prematurely in subcutaneous implantation studies.
• Pulp damage was observed despite limitations including varying cavity depths and small sample sizes.

Conclusions:

• High-copper dental alloys may pose a risk of pulp damage, particularly in deep cavity preparations.
• The use of non-toxic base or lining materials is recommended for high-copper alloys in deep cavities.
• Clinical challenges exist in applying liners and isolating cavities when using these materials, especially in pediatric dentistry.