Non-specific organic chromophores and pigment molecules within dental hard tissues

Non-specific organic chromophores and pigment molecules within dental hard tissues are the chemical entities responsible for the perceived color and discoloration of human teeth. These molecules are primarily located within the organic matrix of the enamel and the more protein-rich dentin, often consisting of complex organic compounds with conjugated double bonds that absorb light in the visible spectrum (Joiner, 2006). They can be classified as extrinsic, resulting from the accumulation of environmental stains like tannins or tobacco, or intrinsic, resulting from systemic factors such as tetracycline staining or the natural aging process of dentin (Kwon & Wertz, 2015). In clinical practice, these molecules are the therapeutic targets for dental bleaching agents, most notably hydrogen peroxide and carbamide peroxide. These agents function by diffusing through the porous hard tissues and generating reactive oxygen species, such as hydroxyl radicals, which oxidatively degrade the chromophores into smaller, non-pigmented fragments (Eimar et al., 2012). While effective for aesthetic improvement, targeting these molecules can lead to transient side effects like dentinal hypersensitivity and gingival irritation due to the penetration of peroxide into the pulp chamber (Carey, 2014). The degradation of these pigments results in a higher light reflectance and a whiter appearance of the tooth structure.

Other names

Dental chromophoresTooth pigmentsIntrinsic and extrinsic dental stainsOrganic dental pigmentsTooth discoloration molecules

Oxidation of conjugated double bonds within organic chromophores, leading to the fragmentation of large pigment molecules into smaller, colorless or lighter-colored compounds.