# Effect of different finishing and polishing procedures on color stability of Ormocer- and methacrylate-based composites

## TL;DR

This study shows that polishing techniques and surface conditions significantly affect the color stability of dental composites over time.

## Contribution

The study identifies optimal polishing and surface preparation methods for improving color stability in two types of dental composites.

## Key findings

- Admira Fusion and Grandio showed lowest ΔE values when polished with abrasives and a 2-step technique.
- Grandio had the highest ΔE value when cured in air without polishing.
- Glycerin coatings improved color stability before polishing.

## Abstract

The optical properties of composite restorations are influenced by composite’s surface conditions and polishing techniques, which can affect stain resistance. This study examined how surface condition and polishing techniques affect the color stability of two composite restorative materials.

A total of 150 composite discs were divided into 30 experimental groups (n = 5) based on composite material (ormocer-based composite, Admira Fusion, and methacrylate-based composite’ Grandio), surface condition (against matrix, air, or glycerin), and polishing technique (No polishing, 1-step, 2-step, abrasive + one-step, and abrasive + two-step). Color measurements were taken using a spectrophotometer before immersion (baseline) and after 3 months of immersion in a coffee solution. Data were analyzed using ANOVA and Tukey HSD test (α = 0.05).

Composite type, surface condition, and polishing technique all had a significant effect on ΔE (P < 0.001). Admira Fusion and Grandio exhibited the lowest ΔЕ value (3.26 ± 0.15, 3.43 ± 0.08 respectively) when polished with abrasives and a 2-step technique (P < 0.05). Grandio showed the highest ΔЕ value (19.66 ± 0.37) when light cured in air and without exposure to any polishing technique (P < 0.05).

The color stability of composites was enhanced by applying glycerin coatings prior to light curing and polishing.