Calcium hydroxyapatite (HAp) is an inorganic chemical compound found in the mineral structure of bones and teeth. It is a crystalline form of calcium phosphate that has the chemical formula Ca10(PO4)6(OH)2.
It is the main mineral substance present in tooth enamel, dentin and bone. It is also responsible for its strength and toughness.
Origin of calcium hydroxyapatite
Calcium hydroxyapatite (HAp) is formed naturally in the human body during the process of bone mineralization. However, it can also be synthesized in the laboratory using different methods. There are different synthesis methods, such as coprecipitation, hydrothermal and electrodeposition. The following are two of the most important:
- Chemical precipitation method:
- The starting point is a solution containing calcium ions (Ca^2+), and phosphate (PO4^3-). These ions can come from sources such as calcium nitrate (Ca(NO3)2) and dibasic ammonium phosphate ((NH4)2HPO4).
- The pH and temperature conditions of the solution are adjusted to promote the precipitation reaction.
- As calcium and phosphate ions are in solution, they combine to form calcium hydroxyapatite crystals.
- The crystals can be collected by filtration and then washed and dried to obtain the final product.
- Method of hydrolysis and subsequent calcination:
- In this method, a calcium phosphate precursor is used, such as dicalcium phosphate (CaHPO4) or tricalcium phosphate (Ca3(PO4)2).
- The precursor undergoes a hydrolysis process, where it reacts with water to form calcium hydroxyapatite.
- After hydrolysis, the products are dried and calcined at high temperatures to promote crystallization and eliminate any impurities or residual water.
- Finally, calcium hydroxyapatite is obtained in the form of crystalline powder.
Calcium hydroxyapatite in esthetics
In aesthetic medicine, calcium hydroxyapatite is used as a dermal filler to correct wrinkles and restore facial volume. Another well-known dermal filler is hyaluronic acid.
It is injected under the skin to smooth and diminish the appearance of wrinkles, as well as expression lines around the mouth and nasolabial folds. The filler material provides immediate volume and improves the appearance of the skin. It is a compound recommended for mature skin. Its effects are prolonged.
It also has the ability to stimulate collagen production in the skin. The injection stimulates the body’s response, promoting collagen production in the treated area. This new collagen gradually replaces the filler substance, so the results are longer lasting and produce lifting-like effects.
It also works to add volume and contour to the cheekbones and chin.
Other uses of calcium hydroxylapatite
This compound is used in different fields and for various purposes, such as medicine and dentistry.
- In the field of dentistry, it is used as a bone filling material in maxillofacial and periodontal surgery. It is used to fill bone defects, such as those caused by tooth extraction or bone loss due to periodontal disease.
- In medicine, it is used in bone implants and fracture repair. Hydroxyapatite has been shown to promote bone growth by providing a favorable environment for regeneration and tissue attachment.
- It is also used in biomaterial applications, to coat metal implants, such as hip prostheses or orthopedic screws.
Commitment to quality
This text on calcium hydroxyapatite has been prepared by professional writers. In addition, we have relied on experts in medicine, engineering and aesthetics as a source of information, as well as specific studies to maintain the quality of what we publish.
At Sisneo Bioscience we are committed to publish truthful and contrasted information. Y a actualizarla o corregirla en cuanto haya nuevos conocimientos.
Among others, we have used the following sources:
- Yutskovskaya Y, Kogan E, Leshunov E. «A randomized, split-face, histomorphologic study comparing a volumetric calcium hydroxylapatite and a hyaluronic acid-based dermal filler» J Drugs Dermatol. 2014 Sep;13(9):1047-52.
- Loghem JV, Yutskovskaya YA, Philip Werschler W. «Calcium hydroxylapatite: over a decade of clinical experience» J Clin Aesthet Dermatol. 2015 Jan;8(1):38-49.