[Comparative clinical study of amalgam fillings]

Area of Science:

• Dental Materials Science
• Clinical Dentistry
• Restorative Dentistry

Background:

• Dental amalgam remains a widely used restorative material.
• Understanding the long-term performance of different amalgam alloys is crucial for clinical success.
• Gamma-2 phase presence in amalgam has been linked to degradation and corrosion.

Purpose of the Study:

• To compare the clinical performance of a non-gamma2 amalgam alloy against a conventional gamma2-containing amalgam alloy.
• To evaluate marginal integrity, bulk fracture, surface roughness, and secondary caries over a two-year period.

Main Methods:

• A clinical study involving 81 patients with 106 contralateral homologous molar tooth-pairs.
• Placement of two different amalgam alloys: Strafill NG2 (gamma2-containing) and googfill 700 (non-gamma2).
• Clinical evaluation after two years assessing specific failure modes.

Main Results:

• A statistically significant difference in marginal ditching was observed, favoring the non-gamma2 amalgam alloy (googfill 700).
• No significant differences were found between the two alloys regarding bulk fracture, surface roughness, or secondary caries development.
• The non-gamma2 alloy demonstrated improved marginal adaptation compared to the gamma2-containing alloy.

Conclusions:

• The absence of the gamma-2 phase in amalgam alloys may enhance marginal integrity, reducing susceptibility to ditching.
• Non-gamma2 amalgam alloys show comparable performance to conventional alloys in terms of bulk fracture, surface integrity, and caries resistance over two years.
• Clinical selection of non-gamma2 amalgams may be beneficial for improved marginal seal in dental restorations.