Sepia Melanin-Loaded Primary Human Gingival Keratinocytes: An In Vitro Model for Studies on Pigmented Gingiva

The objective of this study is the development an in vitro cell culture model pigmented gingival keratinocytes to provide a unique tool assess oral care products such as toothpaste and evaluate whether cells might be less susceptible than unpigmented cytotoxicity by any toothpaste. Sepia melanin at various concentrations was added primary human keratinocyte (HGK) monolayers identify concentration which sufficiently phagocytosed absence cytotoxicity; subsequently used generate HGK model. Extracts from three commercial adult toothpastes (Crest 3D White, Sensodyne, Colgate Optic) different dilutions were evaluated HGKs for over 24 h duration MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay. Results demonstrated that showed concentration-dependent uptake sepia with significant linear correlation pigment uptake. Moreover, distributed perinuclearly cells, similar distribution physiological gingiva vivo. Further experiments conducted 25 µg/mL higher induced cytotoxicity. Evaluation on no differential effects dilution. In summary, ability create controlled level pigmentation demonstrated. Examination extracts revealed both HGKs. conclusion, shows artificially easy low-cost mimics vivo pigmentation. HGKs, suggesting presence did not impart protective effects. studies employ large number include repeated exposures longer are warranted.