Calcium Hydroxylapatite in Regenerative Aesthetics: Mechanistic Insights and Mode of Action.

Calcium hydroxylapatite-carboxymethylcellulose (CaHA-CMC) is a widely utilized soft tissue filler known for its compatibility with human tissue and for its effective volumizing properties. The biodegradable CaHA microspheres function as a scaffold for the formation of new tissue by stimulating a variety of cellular responses leading to the production of collagen, elastin, vasculature, and proteoglycans and thereby enhance skin quality. Despite the promising regenerative effects of CaHA-CMC, substantial gaps remain in understanding its precise underlying mechanisms, and addressing these gaps is crucial to optimizing its clinical applications. A literature search was conducted with PubMed, Google Scholar, and Web of Science for keywords, including "calcium hydroxylapatite," "tissue regeneration," "macrophages," "fibroblasts," and "calcium." This review elucidates the novel mechanisms of CaHA-CMC action within aesthetic medicine, with a focus on the dynamic interactions between macrophages and fibroblasts. The key role of calcium ions as critical biological cues in directing skin regeneration pathways is explored alongside an examination of the distinct physicochemical properties of CaHA-CMC. CaHA-CMC helps in tissue regeneration by providing calcium ions that act as key biological cues, promoting fibroblast activity and collagen production.