# Selected Properties of Composite Materials Used for Dental Fillings—Methodological Development and Preliminary Results

## TL;DR

This study examines the mechanical and tribological properties of dental composites to understand how their structure affects performance in dental fillings.

## Contribution

A new methodological approach is introduced to evaluate dental composites under controlled conditions, linking material structure to functional properties.

## Key findings

- Filler composition and surface topography significantly influence the mechanical and tribological performance of dental composites.
- Estelite Asteria showed the highest hardness but also the highest wear, while Enamel Plus HRi had the highest Young’s modulus.
- Materials with complex surface morphology retained saliva better, reducing friction but not necessarily wear.

## Abstract

Dental composites are widely used in restorative dentistry; however, their long-term clinical performance is strongly influenced by mechanical and tribological behavior under oral conditions. Understanding the relationship between material structure, surface characteristics, and functional properties is therefore essential. This preliminary methodological study evaluated the mechanical, tribological, and wetting properties of three light-cured dental composites—Enamel Plus HRi, Amaris, and Estelite Asteria—commonly used in clinical practice. The materials were characterized in terms of surface morphology, hardness, Young’s modulus, coefficient of friction, and wear resistance under controlled laboratory conditions. Instrumental indentation and tribological tests were performed, and results were expressed as mean values with standard deviations calculated from multiple measurements. The results demonstrated that filler composition and surface topography affected material performance. Estelite Asteria exhibited the highest hardness (HIT > 300 MPa), while Enamel Plus HRi showed the highest Young’s modulus (EIT ≈ 14.5 GPa). Materials with more complex surface morphology retained lubricating artificial saliva more effectively, resulting in lower friction coefficients (minimum µ = 0.85), although this did not reduce wear. The highest wear was observed for Estelite Asteria, with a wear scar approximately 62% greater than that of Enamel Plus HRi. These preliminary findings provide a methodological basis for further investigations under more clinically relevant conditions.