Organic chromophores in tooth enamel and dentin

Organic chromophores in tooth enamel and dentin are the chemical entities responsible for the perceived color and discoloration of human teeth. These chromophores are primarily located within the organic matrix of the dentin and the interstitial spaces of the enamel rods, consisting of complex organic molecules such as polyphenols, carotenes, and protein-derived pigments (Kwon & Wertz, 2015). They can be classified as extrinsic, arising from external sources like coffee or tobacco, or intrinsic, resulting from systemic conditions, aging, or trauma (Joiner, 2006). In clinical practice, these molecules serve as the primary target for dental bleaching agents, most notably hydrogen peroxide and carbamide peroxide. These agents release reactive oxygen species that penetrate the tooth structure and oxidize the double bonds within the chromophores, breaking them down into smaller, lighter-colored constituents (Eimar et al., 2012). This oxidative process effectively reduces the concentration of light-absorbing molecules, thereby increasing the overall lightness of the tooth. While effective for aesthetic improvement, targeting these chromophores can lead to transient side effects such as dentin hypersensitivity and gingival irritation due to the diffusion of peroxide into the pulp chamber (Carey, 2014). Understanding the distribution and chemical nature of these chromophores is essential for optimizing whitening efficacy while minimizing damage to the mineralized dental tissues.

Other names

Dental chromophoresTooth pigmentsIntrinsic stainsExtrinsic stainsOrganic dental matrix pigments

Oxidative degradation of organic double bonds and cleavage of complex pigment molecules into smaller, colorless fragments through the release of reactive oxygen species.