CALCIUM PHOSPHATE
The key technology to regenerate your bones
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- Réaction de prise de l’α-TCP : 3(α-Ca3 (PO4 )2) + H2O → Ca9(PO4)5(HPO4)OH; α-Ca3 (PO4 )2 = α-TCP; Ca9(PO4)5(HPO4)OH = CDADissolution : Les particules d’α-TCP se dissolvent dans l’eau, libérant des ions Ca2+ et PO43-.
- La sursaturation du milieu, suite la dissolution de l’alpha-TCP (alpha tricalcium phosphate), conduit à la nucléation et à la croissance de la CDA (Calcium Déficient Apatite), une structure ostéoconductive et ostéointégrable ressemblant au minéral osseux.
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Croissance des cristaux de CDA à la suite de la nucléation formant un réseau de cristaux qui se chevauchent pour former une matrice solide
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La matrice poreuse du QS composée de CDA améliore les échanges de fluides et d’ions à la surface du biomatériau ainsi que l’adsorption des protéines qui attirent les cellules osseuses. A travers les pores, les ostéoclastes, colonisent le QuickSet et adhèrent à sa surface via leur membrane plissée. Elles libèrent des acides et des enzymes favorisant la résorption du QuickSet. Les facteurs de croissance activent les macrophages M2 afin de favoriser la cicatrisation des plaies et d’initier la migration des cellules progénitrices vers le site.
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Les ostéoblastes, cellules progénitrices, pénètrent dans le QuickSet à travers les pores et se fixent dans la lacune de résorption. Ces cellules génèrent et déposent des composants de matrice extracellulaire (MEC), principalement du collagène de type I, le principal composant protéique de l’os.
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À la suite de ces réactions, la croissance osseuse se poursuit alors que les cellules nouvellement recrutées continuent à fonctionner et facilitent la croissance et la réparation des tissus. Quickset continue à se dégrader et à être converti en Matrice extra cellulaire.
HISTORY
Calcium phosphate plays a central role in the field of biomaterials as it is chemically and structurally similar to the mineral phase of human bone. Long before being used as a synthetic biomaterial, calcium phosphate was identified as the main inorganic component of skeletal tissue, primarily in the form of biological hydroxyapatite.
In the first half of the 20th century, researchers studying bone chemistry established that bone mineral is not an inert structure, but a dynamic, calcium phosphate–based material constantly remodeled by the body. This fundamental discovery laid the groundwork for the idea that a synthetic material mimicking bone mineral could be accepted by the human body rather than rejected.
In the late 1960s and early 1970s, as orthopaedic and reconstructive surgeries increased, clinicians faced a major limitation: the lack of safe and abundant bone graft material. Autografts were limited in quantity and associated with donor-site morbidity, while metals and polymers often failed to integrate with bone. This challenge prompted researchers to revisit the chemistry of bone itself.
Inspired by the natural composition of skeletal tissue, scientists began synthesizing calcium phosphate ceramics, primarily hydroxyapatite and tricalcium phosphate. Early work led by pioneers such as Klaas de Groot and Robert Z. LeGeros demonstrated that synthetic calcium phosphate materials were biocompatible, non-toxic, and capable of supporting bone growth.
One of the most decisive moments came when porous calcium phosphate implants were placed in bone defects during preclinical and clinical studies. Rather than being encapsulated or rejected, the material allowed bone cells to migrate along its surface and through its pores. Researchers observed a phenomenon that would later be defined as osteoconduction: bone grew directly on and within the calcium phosphate structure, gradually anchoring the implant to the host tissue.
By the late 1970s and early 1980s, it became clear that not all calcium phosphates behaved the same way in vivo. Hydroxyapatite proved to be highly stable and slowly resorbable, while β-tricalcium phosphate exhibited faster resorption, making it suitable for applications where gradual replacement by natural bone was desired. This led to the development of biphasic calcium phosphates, combining stability and controlled resorption to better match physiological bone healing.
Throughout the 1980s and 1990s, calcium phosphate substitutes were progressively validated in orthopaedics, traumatology, maxillofacial surgery, and dental applications. Their ability to act as a temporary scaffold for bone regeneration, without inducing adverse immune reactions, marked a turning point in regenerative medicine. Unlike metals or inert polymers, calcium phosphate materials were no longer perceived as foreign bodies, but as biofunctional extensions of bone itself.
By the early 21st century, calcium phosphate had become one of the most widely studied and clinically used bone substitute materials worldwide. Thousands of scientific publications confirmed its safety, versatility, and regenerative potential. Today, calcium phosphate remains a cornerstone of bone regeneration strategies, continuously refined through advances in porosity control, mechanical performance, and biological interaction, with the shared objective of restoring — and ultimately regenerating — functional bone tissue.