Biocompatibility and Osteogenesis of Calcium Phosphate Cement Scaffolds for Bone Tissue Engineering

2013

JFB

152

107

In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are bioactive and biodegradable grafting bioceramics in the form of a powder and a liquid. After mixing, both phases form pastes, which set and harden forming either a non-stoichiometric calcium deficient hydroxyapatite or brushite. Since both of them are remarkably biocompartible, bioresorbable and osteoconductive, self-setting calcium orthophosphate formulations appear to be promising bioceramics for bone grafting. Furthermore, such formulations possess excellent molding capabilities, easy manipulation and nearly perfect adaptation to the complex shapes of bone defects, followed by gradual bioresorption and new bone formation. In addition, reinforced formulations have been introduced, which might be described as calcium orthophosphate concretes. The discovery of self-setting properties opened up a new era in the medical application of calcium orthophosphates and many commercial trademarks have been introduced as a result. Currently such formulations are widely used as synthetic bone grafts, with several advantages, such as pourability and injectability. Moreover, their low-temperature setting reactions and intrinsic porosity allow loading by drugs, biomolecules and even cells for tissue engineering purposes. In this review, an insight into the self-setting calcium orthophosphate formulations, as excellent bioceramics suitable for both dental and bone grafting applications, has been provided.

Section: Recent Achievements and Future Developmentsmentioning

confidence: 99%

Self-Setting Calcium Orthophosphate Formulations

2013

JFB

152

107

“…Therefore, until recently it was impossible to produce resorbable preset low-temperature hydrated 3D bioceramics for various applications, e.g., scaffolds and granules, from low-temperature calcium orthophosphate phases, such as ACP, DCPA, DCPD, OCP and CDHA. Now, using the appropriate techniques, open macroporous 3D scaffolds consisting of the aforementioned low-temperature phases (currently, excluding ACP and OCP) can be produced via a cementitious reaction [297,327,333,334,412,[602][603][604], thus dramatically widening the application of these calcium orthophosphates as biomaterials and bioceramics. This type of biomaterials could be very promising for tissue engineering applications.…”

Section: Future Developmentsmentioning

confidence: 99%

Self-Setting Calcium Orthophosphate Formulations: Cements, Concretes, Pastes and Putties

2012

IJMC

In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are a bioactive and biodegradable grafting material in the form of a powder and a liquid. Both phases after mixing form a viscous paste that after being implanted sets and hardens within the body as either a non-stoichiometric calcium deficient hydroxyapatite (CDHA) or brushite, sometimes blended with un-reacted particles and other phases. As both CDHA and brushite are remarkably biocompartible and bioresorbable (therefore, in vivo they can be replaced with a newly forming bone), self-setting calcium orthophosphate cements represent a good correction technique of non-weight-bearing bone fractures or defects and appear to be very promising materials for bone grafting applications. Besides, these cements possess an excellent osteoconductivity, molding capabilities, and easy manipulation. Nearly perfect adaptation to the tissue surfaces in bone defects and a gradual bioresorption followed by new bone formation are additional distinctive advantages of calcium orthophosphate cements. Besides, reinforced formulations are available; those are described as calcium orthophosphate concretes. Furthermore, formulations with high viscosity, such as pastes and putties are also known. The discovery of self-setting formulations has opened up a new era in the medical application of calcium orthophosphates; several commercial compositions have already been introduced as a result. Many more formulations are in experimental stages. In this review, an insight into the self-setting calcium orthophosphate formulations, as excellent biomaterials suitable for both dental and bone grafting applications, has been provided.

“…The alternatives include use of hierarchical bioactive scaffolds to engineer in vitro living cellular constructs for transplantation or use of bioresorbable bioactive particulates or porous networks to activate in vivo the mechanisms of tissue regeneration [ 629 , 630 ]. Thus, the aim of calcium orthophosphate bioceramics is to prepare artificial porous scaffolds able to provide the physical and chemical cues to guide cell seeding, differentiation and assembly into 3D tissues of a newly formed bone [ 587 , 631 , 632 , 633 , 634 , 635 ]. Particle sizes, shape and surface roughness of scaffolds are known to affect cellular adhesion, proliferation and phenotype.…”

Section: Calcium Orthophosphate Bioceramics In Tissue Engineeringmentioning

confidence: 99%

Calcium Orthophosphates as Bioceramics: State of the Art

2010

JFB

218

112

In the late 1960s, much interest was raised in regard to biomedical applications of various ceramic materials. A little bit later, such materials were named bioceramics. This review is limited to bioceramics prepared from calcium orthophosphates only, which belong to the categories of bioactive and bioresorbable compounds. There have been a number of important advances in this field during the past 30–40 years. Namely, by structural and compositional control, it became possible to choose whether calcium orthophosphate bioceramics were biologically stable once incorporated within the skeletal structure or whether they were resorbed over time. At the turn of the millennium, a new concept of calcium orthophosphate bioceramics—which is able to promote regeneration of bones—was developed. Presently, calcium orthophosphate bioceramics are available in the form of particulates, blocks, cements, coatings, customized designs for specific applications and as injectable composites in a polymer carrier. Current biomedical applications include artificial replacements for hips, knees, teeth, tendons and ligaments, as well as repair for periodontal disease, maxillofacial reconstruction, augmentation and stabilization of the jawbone, spinal fusion and bone fillers after tumor surgery. Exploratory studies demonstrate potential applications of calcium orthophosphate bioceramics as scaffolds, drug delivery systems, as well as carriers of growth factors, bioactive peptides and/or various types of cells for tissue engineering purposes.