Marginal integrity of amalgam restorations.

Area of Science:

• Restorative Dentistry
• Dental Materials Science
• Clinical Dental Research

Background:

• Dental amalgam remains a widely used restorative material.
• Understanding the long-term performance of different amalgam alloys is crucial for clinical decision-making.
• The influence of particle morphology and finishing techniques on amalgam longevity requires further investigation.

Purpose of the Study:

• To compare the clinical quality of dental restorations made with lathe-cut versus spherical amalgam alloys over a four-year period.
• To evaluate the impact of finishing techniques on the marginal integrity and overall quality of amalgam restorations.
• To assess the durability and performance differences between two common amalgam alloy types.

Main Methods:

• Thirty-eight Class II cavities in dental students were restored with either lathe-cut or spherical amalgam alloys.
• Cavity preparation quality was intentionally varied, with one part unfinished and the rest well-finished.
• Restoration quality was assessed clinically and via scanning electron microscopy of replicas at baseline, post-restoration, and after one and four years.

Main Results:

• After four years, restorations utilizing lathe-cut amalgam exhibited significantly better quality compared to those made with spherical amalgam.
• No statistically significant difference in restoration quality was observed based on variations in margin finishing techniques.
• Clinical evaluation and scanning electron microscopy corroborated the superior long-term performance of lathe-cut amalgam.

Conclusions:

• Lathe-cut amalgam alloys offer superior long-term clinical quality for Class II restorations compared to spherical amalgam alloys.
• The finishing technique of cavity margins does not appear to be a significant factor in the four-year quality of these amalgam restorations.
• These findings suggest that amalgam alloy particle morphology plays a critical role in the durability of dental restorations.