Abstract : Dental bleaching, while effective for tooth whitening, often leads to enamel demineralization, manifesting as increased surface roughness and reduced microhardness. This literature review systematically evaluates the efficacy of eggshell powder (ESP) and nano-hydroxyapatite (nHA) as remineralizing agents for bleached enamel, comparing their performance with established commercial products such as casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and fluoride-based agents. A literature review was conducted, including peer-reviewed in-vitro studies published in English that quantitatively assessed the remineralization effects of eggshell powder or nanohydroxyapatite on bleached enamel. Studies were selected based on the use of standardized microhardness or surface roughness measurements and the presence of control groups, with no restrictions on publication date. Data extraction focused on study design and key findings related to enamel remineralization. Findings indicate that both ESP and nHA significantly restore enamel microhardness and reduce surface roughness, with results comparable to or, in some cases, approaching those of CPP-ACP. ESP, derived from calcined chicken eggshells, offers a sustainable and cost-effective remineralization strategy, while nHA’s biomimetic properties facilitate deep mineral penetration and adhesion.