Novel Microscalpels for Removing Proximal Composite Resin Overhangs on Class II Restorations

Area of Science:

• Dental Materials Science
• Restorative Dentistry
• Biomaterials Engineering

Background:

• Interdental access for excess material removal in Class II composite restorations is challenging.
• Limited evidence-based guidelines exist for interproximal finishing procedures.
• Novel microscalpels are introduced for improved interproximal finishing of composite resin restorations.

Purpose of the Study:

• To evaluate the fracture strength and cutting efficiency of novel microscalpels.
• To compare microscalpels against traditional instruments including scalers, oscillating devices, finishing strips, and conventional scalpels.
• To assess the marginal quality and quantity of excess material removed by each device.

Main Methods:

• Fracture strength (LOAD) and cutting forces (CUT) of microscalpels were measured at various angles (15-75 degrees) using a universal testing machine.
• In vitro comparison of devices using standardized composite overhangs.
• Scanning electron microscopy (SEM) evaluated marginal quality (QUAL) and quantity of excess/deficit (QUAN).

Main Results:

• Microscalpels exhibited the highest fracture strength and lowest cutting force at a 15-degree angle.
• Scalpel size 12 yielded the highest percentage of perfect margins (QUAL).
• Microscalpels removed the least amount of excess material (QUAN), while finishing strips removed the most. Scalers caused fractures.

Conclusions:

• Microscalpels can cut composite resin at forces significantly lower than their fracture threshold.
• Smaller or curved scalpels are recommended for achieving superior margin quality in composite restorations.