Setting behavior and bioactivity assessment of calcium carbonate cements

Abstract

Calcium carbonate cements have emerged in the last few years as an attractive candidate for biomedical applications. They can be easily prepared by mixing water with two metastable calcium carbonate phases––amorphous calcium carbonate (ACC) and vaterite––which (re)crystallize into calcite during setting reaction. The transformation kinetics (and therefore the final surface cement composition) strongly depends on the initial mixture design and is controlled by the dissolution of ACC, whereas calcite nucleation typically controls their recrystallization in fluid batch experiments. Novel compositions are presented in this paper by incorporating organic molecules as a proxy to test their capability to carry on other biomolecules like proteins or antibiotics. The hardened samples are microporous and show excellent bioactivity rates, although their mechanical properties still remain poor. However, this would not be a handicap for in‐vivo applications such as bone filling, especially in low mechanical stress locations.

Calcium carbonate: controlled synthesis, surface functionalization, and nanostructured materials

“…The adsorption of octanoic acid on the CaCO 3 surface within the microstructure of CaCO 3 cements has been shown to have no effect on the CaCO 3 (re)crystallization progress. 229 This observation opens up the possibility of functionalizing CaCO 3 cements with other biomolecules such as proteins, growth factors, stem cells or antibiotics, which may enhance the protein adhesion, bactericidal effects, or drug release of cements without modifying the crystallization pathway of CaCO 3 . These CaCO 3 cements functionalized with biomolecules exhibit high solubility, fast setting kinetics, and bioactive properties.…”

“…226,227 Moreover, CaCO 3 is not only a possible calcium source for the preparation of calcium-based materials such as hydroxyapatite and other CaP salts due to its fast biodegradability, 228 but is also a functional additive that can be incorporated into CaP-based cements to improve their performances in bioresorbability and bone formation. 225,229 The slow resorption rate of bone graft substitutes, such as CaP cements and apatite, inhibits their replacement by new bone tissues and ultimate bone defect repair. 230 Biological resorption mainly depends on the solubility of the mineral components.…”

On the physicochemical properties, setting chemical reaction, and in vitro bioactivity of aragonite–chitosan composite cement as a bone substitute

“…40 It was also reported that magnesium inhibits calcite crystal growth. 41 That is why the lack of magnesium and the presence of calcite impurities in ACC synthesised by Sanchez et al 3 led to the CCC end-product containing calcite as the dominant phase with some unreacted vaterite. Myszka et al 2 used a mixture of vaterite and Mg-stabilised ACC and SBF solution to prepare CCC mainly comprising vaterite with small amounts of aragonite, calcite, and unreacted ACC after setting.…”

“…Calcium carbonate cements (CCC) have been suggested as bioactive mineral cements complementary to calcium phosphate cements (CPCs), particularly when a faster resorption rate is needed for some non-load-bearing orthopaedic applications. [1][2][3] Indeed, the presence of a calcium carbonate (CaCO 3 ) metastable phase such as aragonite and/or vaterite in the end-product should confer a higher in vivo biodegradation rate than that of the CPC. In addition, some recent studies showed that CaCO 3 cements can provide processing and performance decisive advantages such as the use of CO 2 as a precursor of CaCO 3 compounds for sustainable and carbon-negative building material applications over conventional inorganic binders.…”

“…More recently, Myszka et al 2 examined a calcium carbonate cement based on vaterite as a main phase and its mechanical reinforcement using poly-hydroxyethyl-methacrylate to produce a high-strength bone cement. Sanchez et al 3 reported a calcium carbonate cement by combining Mg-free ACC and vaterite leading to calcite as a major component of the cement. Nevertheless, in the aforementioned studies, the setting mechanism of calcium carbonate cements and the control of their composition were not fully elucidated.…”