Purpose
To assess how different polishing-treated dental composite resins change color over time when exposed to common staining beverages, and to compare how different composites and stains perform.
Materials & Methods
- Specimens: 288 disk-shaped samples (10 mm diameter, ~1.2 mm thick, then polished to 1 mm) made from eight different composite resin materials, shade A2 or equivalent. docs.saremco.ch
- Polishing: Surfaces polished sequentially using abrasive papers of increasing fineness (500 → 4000 grit). docs.saremco.ch
- Baseline Measurement: Stored 24 h at 37 °C; initial color measured with a spectrophotometer with both black and white backgrounds. docs.saremco.ch
- Staining Exposure: Samples divided into 6 groups, immersed for 28 days in one of five staining solutions (red wine, orange juice, Coca‑Cola, tea, coffee) or in artificial saliva (control). Solutions refreshed weekly; after 28 days the specimens cleaned and color re‑measured. docs.saremco.ch
- Measurement of Color Change: Used the CIEDE2000 (ΔE₀₀) formula to quantify how much color changed (including changes in lightness, chroma, hue). docs.saremco.ch
Key Findings
- All tested composite resins showed significant color changes after 4 weeks in staining solutions (versus control). docs.saremco.ch
- Among the staining agents, red wine caused the greatest discoloration, followed by coffee, tea, orange juice, coke; artificial saliva caused minimal change. docs.saremco.ch
- With a white background, ΔE₀₀ values ranged from ≈0.5 (best case: nearly no visible change in saliva for some materials) to ≈51.1 (worst case: with red wine on some composites). docs.saremco.ch
- When grouping all stains together for each material:
- Best performers: Saremco Microhybrid and ELS. docs.saremco.ch
- Moderate: Estelite Posterior also did relatively well. docs.saremco.ch
- Worst performers: Filtek Supreme and Tetric Bulk Fill showed highest staining susceptibility. docs.saremco.ch
- Polished specimens showed less discoloration compared to similar unpolished specimens in a previous study. Polishing seems to reduce—but not eliminate—staining. docs.saremco.ch
Interpretation & Implications
- Composite composition matters: Differences in resin matrix (monomers) and filler types as well as their proportions appear to influence how much staining happens. For example, materials with more hydrophobic monomers or high inorganic filler content tend to resist staining better. docs.saremco.ch
- Polishing helps: Surface finishing reduces discoloration, likely by reducing surface roughness and removing superficial reactive layers that might soak up stains. docs.saremco.ch
- Clinical relevance: If a dentist or product developer wants color stability over time (especially in areas where aesthetic demand is high), choice of composite material plus a good polishing protocol are important. Also, patients’ diets (red wine, coffee, etc.) will affect long‑term color stability.
- The study was in vitro, so real‐world results may differ (due to dynamic oral environment, cleaning habits, etc.). docs.saremco.ch