Bioceramics refers to a type of ceramic materials used for specific biological or physiological functions, that is, directly Ceramic materials used in the human body or in biology, medicine, biochemistry, etc. related to the human body. Broadly speaking, all ceramic materials belonging to bioengineering are collectively called bioceramics. The main advantages of bioceramic materials are biocompatibility and osteoconductivity, and they can show good affinity with cells and other biological tissues, so they have very important applications in the medical field.
Bioceramic materials have the characteristics of stainless steel materials and plastic materials. They also have good hydrophilicity and can maintain good affinity with biological tissues and cells in living organisms. Compared with traditional ceramic materials, current bioceramics are not limited to polycrystals, but also include single crystals, non-biological glass, glass-ceramics, gradient materials, inorganic materials and composite materials; ceramic materials suitable for repair and reconstruction of human hard tissue.
Bioceramic materials can be divided into bioinert ceramics and bioactive ceramics< /span>
Bio-inert ceramics mainly refers to chemically stable, biologically inert ceramics Ceramic materials with good compatibility, such as alumina, zirconia and medical carbon materials, have a relatively stable structure, strong bonding forces in the molecules, and have high strength, wear resistance and Chemical stability.
1. After the alumina ceramic is implanted into the human body, an extremely thin fibrous membrane is formed on the surface. There is no chemical reaction at the interface. It is mostly used for total hip reduction and repair and the connection of the femur and hip bone.
2. Zirconia ceramics are stable in the human body and have higher fracture toughness and wear resistance than alumina, which is helpful for reducing implant size and achieving low friction and wear for manufacturing Tooth roots, bones, hip joints, composite ceramic artificial bones, valves, etc.
Bioactive ceramics include surface bioactive ceramics and bioactive ceramics Absorbent ceramics, also called biodegradable ceramics; include bioactive glass, hydroxyapatite ceramics, tricalcium phosphate ceramics, etc.
1. Bioglass ceramics contain more calcium and phosphorus than ordinary window glass, which can naturally and firmly chemically combine with the bone, and can quickly produce a series of surface reactions at the implant site. Leads to the formation of a phosphate-based apatite layer; has good biocompatibility, and the material is implanted in the body without reactions such as rejection, inflammation, and tissue necrosis. It can form bony combination with bone and form bone quickly; used for repair Ear ossicles, which have a good effect on restoring hearing.
2. The composition of hydroxyapatite (HA) is similar to that of natural apatite mineral. It is the main inorganic component of vertebrate bones and teeth. Its structure is also very similar. It is used as a bone substitute. in bone transplantation. HA has good biocompatibility. It is not only safe and non-toxic when implanted in the body, but can also conduct bone growth. It is a typical bioactive ceramic that can form chemical bonds with tissues at the interface after being implanted in the body.
3. Tricalcium phosphate has good biocompatibility and can be directly integrated with the bone after implantation into the body without any local inflammatory reaction or systemic toxic side effects. Compared with other ceramics, it is more similar to the properties and structure of human bones and natural teeth. The disadvantage is that the mechanical strength is low and it cannot withstand strong impact. Tricalcium phosphate ceramics are mixed with other materials to make biphasic or multiphase ceramics. , is one of the methods to improve its mechanical strength.
