Because calcium hydroxyapatite cannot be directly injected into human body, it must be suspended in a gel-like carrier composed of water (distilled water for USP injection) and glycerol (USP), forming semi-solid implantation characteristics and facilitating injection. Due to the above composition characteristics, microcrystalline porcelain has good biocompatibility and biodegradability. Microcrystalline porcelain suspended in gel is a fine spherical crystal with a size between 25 and 45 microns. When injected into human tissues, these stable and smooth microcrystalline porcelain balls will form a skeleton, so that new collagen can be alternately embedded in tissues. This stable and soft frame forms a lasting result. Cream-like microcrystalline porcelain is gel-like, and its excellent shaping effect is formed by microcrystalline porcelain balls and human tissues. Soft and natural, it can keep the shaping effect for several months to two years. RADIESSE microcrystalline porcelain is a kind of calcium-containing compound with no toxicity, antigenicity, carcinogenicity and allergy, and it is one of the normal components of human body. It has been used in human clinical practice for 25 years, and has been approved by FDA of the United States and CE Mark of the European Union as a soft tissue filler for facial shaping. Interpretation: The essence of this product is calcium hydroxyapatite microspheres with a size of 25~45 microns, suspended in a gel-like carrier solution, and its main components are water, glycerol and gel/collagen that can be absorbed by the human body (the details need to be clarified and modified). In terms of chemical composition, mainly calcium and phosphorus are similar to the basic components of teeth, so it is called "porcelain"; Judging from the particle size of the material, it is microspheres of tens of microns, so it is called "microcrystal"; The rest is water, glycerin gel, etc., which can be absorbed by human body or even simple self-components, and has good biocompatibility, so it is called "biological soft ceramics". The diameter of microspheres is 25~45 microns, which is an ideal size, large enough to escape the phagocytosis of macrophages, and small enough to penetrate into the collagen fiber network in the deep dermis through the tiny pinhole of 27G. When the microspheres enter the plastic part, they can be completely wrapped and fixed by the slender fiber membrane and will not move any more. After several months, the injected gel/collagen gradually degrades and is replaced by the human body's own collagen. However, hydroxyapatite microspheres degrade very slowly and can stay in plastic parts for a long time to play a filling role. Moreover, hydroxyapatite has good histocompatibility, no rejection after implantation, safety and reliability, high success rate, no toxicity and no stimulation to tissues. After implantation, the surrounding tissue cells will not die, dissolve or deform, not only will they not be absorbed, but also can prevent the surrounding bones from being absorbed, which has the effect of bone induction and forms a direct bone combination with the tissues and bones. This ingredient has been used in clinic for more than 20 years, and it is very close to the composition of human bones and teeth. It has passed the certification of FDA and EU CE mark abroad, but it has not yet obtained the clinical application license in Chinese mainland. Hydroxyapatite (H.A.), also known as calcium hydroxyapatite, is an artificial bone (in fact, there are many kinds of artificial bones, not limited to this one).