Resorbable bioceramics based on stabilized calcium phosphates. Part I: rational design, sample preparation and material characterization

• Published in: Biomaterials Vol. 20; no. 18; pp. 1727 - 1741
• Main Authors: Langstaff, S., Sayer, M., Smith, T.J.N., Pugh, S.M., Hesp, S.A.M., Thompson, W.T.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.09.1999; Elsevier Science
• Subjects: Bioceramic; Biocompatible Materials - chemistry; Biological and medical sciences; Bone; Bone Remodeling; Bone Substitutes - chemistry; Calcium compounds; Calcium Phosphates - chemistry; Ceramic materials; Durapatite - chemistry; Fourier transform infrared spectroscopy; High temperature effects; Humans; Hydroxyapatite; Medical sciences; Orthopedics; Osteoclast; Osteoclasts - metabolism; Phase composition; Precipitation (chemical); Reference Standards; Resorbable; Spectrophotometry, Infrared; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Technology. Biomaterials. Equipments; Thin films; Tricalcium phosphate; X ray diffraction analysis; X-Ray Diffraction; Tricalcium phosphate; Resorbable; Hydroxyapatite; Osteoclast; Orthopedics; Bioceramic; Orthopedic surgery; Phase composition; Manufacturing process; Calcium phosphate; System design; Properties of materials; Absorbable; Biomaterial; Ceramic materials
• DOI: 10.1016/S0142-9612(99)00086-1
• ISSN: 0142-9612

It has long been the goal of biomaterials research in the field of orthopedics to develop synthetic structures exhibiting comprehensive bioactivity. In particular, an ideal bone-biomaterial would support the activity of osteoblasts in the development of new bone, while simultaneously being resorbed by osteoclasts as part of the lifelong orderly process of bone remodelling. Such resorbable calcium phosphate-based thin films and bulk ceramics have now been created by the high-temperature processing of a fine precipitate, formed from a colloidal sol and stabilized using an additive such as silicon. The materials have two characteristic features: a phase composition which is a mixture of calcium hydroxyapatite and a silicon stabilized tricalcium phosphate, and a microporous morphology based on inter-connected particles (0.2–1 μm in diameter). X-ray diffraction, infrared spectroscopy, nuclear magnetic resonance spectroscopy, and light scattering experiments indicate that the characteristic phase composition arises during sintering through substitution reactions where silicon enters the calcium phosphate lattice under conditions of high chemical reactivity. The crystallographic features are linked through the glaserite form of the apatite structure.