Effect of pH on element release from dental casting alloys

Area of Science:

• Dental Materials Science
• Biocompatibility Studies
• Corrosion Science

Background:

• Dental casting alloys face transient acidity in the oral cavity.
• Limited research exists on the impact of these acidic conditions on elemental release.
• Elemental release is a key factor influencing the biocompatibility of dental alloys.

Purpose of the Study:

• To test the hypothesis that acidic environments increase elemental release from dental alloys during and after exposure.
• To investigate the effect of varying pH levels on elemental release from different alloy types.
• To compare elemental release post-exposure with baseline levels.

Main Methods:

• Exposure of high-noble, noble, and base metal casting alloys to solutions with pH 1-7 for 30 minutes.
• Measurement of elemental release using atomic absorption spectrometry during and after acid exposure.
• Comparison of elemental release during and after exposure to baseline release rates.

Main Results:

• High-noble and noble alloys demonstrated resistance to acidic environments.
• A pH of 4 did not affect elemental release from any alloy type.
• Nickel-based alloys showed significantly increased nickel release at pH 1 and 4, persisting after exposure, unlike noble alloys.

Conclusions:

• Transient acidic exposure significantly elevates elemental release from nickel-based alloys.
• High-noble and noble alloys remain largely unaffected by transient acidic conditions.
• Findings highlight the potential biocompatibility concerns associated with nickel-based alloys in acidic oral environments.