Coffee-related discoloration of composite restorations is one of the most common aesthetic complaints in restorative dentistry. While often perceived by patients as a hygiene issue, current evidence clearly demonstrates that this is primarily a material–diet interaction.
Recent research provides clinically relevant insight into both the mechanism and prevention of this phenomenon.
A 2026 in-vitro study by Gülşah Aşik, Fatmanur Ari, Abdulkadir Özçinar, and Mehmet Buldur, published , evaluated the effect of whitening mouthrinses on coffee-stained composite materials.
Study Highlights:
- Composite specimens were exposed to daily coffee immersion for 3 months (simulating clinical consumption patterns)
- Whitening mouthrinses were applied following exposure
- Optical parameters assessed included:
- Color change (ΔE₀₀)
- Translucency (ΔTP)
- Whiteness index (ΔWID)
Key Findings:
- Coffee caused significant discoloration in all composite materials
- Hydrogen peroxide–containing mouthrinses significantly reduced staining (p < 0.05)
- These rinses maintained colour stability but did not produce clinically visible whitening
- No significant adverse effect on translucency was observed
Understanding the Mechanism
Discoloration occurs due to:
- Adsorption of pigments onto the composite surface
- Absorption (diffusion) into the resin matrix
- Influence of:
- Filler size and distribution
- Resin matrix composition
- Surface roughness
Coffee contains chromogenic compounds (tannins, polyphenols) that penetrate composite materials more readily than enamel.
Hydrogen peroxide works by:
- Oxidizing these chromogens
- Breaking down stain molecules before deep penetration
- Limiting cumulative discoloration over time
Clinical Considerations
- Evidence is primarily in vitro
- Long-term intraoral effects require further validation
- Excessive use of peroxide products may cause:
- Mild mucosal irritation
- Transient sensitivity
Coffee-related staining of composite restorations is inevitable but manageable.
With evidence-based guidance—simple rinsing habits, selective use of peroxide mouthrinses, and regular maintenance—dentists can extend aesthetic longevity without unrealistic restrictions.
REFERANCE
Title: Preventive effects of whitening mouthrinses against coffee-induced discoloration in different types of resin composites: a daily-use in-vitro study
Authors: Gülşah Aşik, Fatmanur Ari, Abdulkadir Özçinar, Mehmet Buldur
Journal: Odontology (2026)
https://doi.org/10.1007/s10266-026-01329-z
