Avaliação de cimento de hidroxiapatita carbonatada: desenvolvimento, caracterização e citotoxicidade

Abstract

Biological apatite has carbonate ions in its composition, which play an important mechanical and biological role, such as the possibility of adjusting and forming granules of varying shapes and sizes, allowing bone to be neoformed through the material. For this reason, its wide availability, low cost and ease of handling mean that carbonate hydroxyapatite-based bone cements are gaining prominence in surgical applications for bone reconstruction and regeneration. The aim of this study is to create carbonate-substituted nanoparticulate hydroxyapatite (HAC) and produce a carbonated hydroxyapatite bone cement (CHAC). In order to achieve this objective, the initial substances and cements were synthesized and subjected to physicochemical analysis. Subsequently, they were tested in a laboratory setting using a cell coculture of L929 and MC3T3. The study examined three samples: pure hydroxyapatite cement (CHAP), CHAC with 5% carbonate (CHAC5), CHAC with 10% carbonate (CHAC10). The characterization was assessed using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), contact angle measurements, pH testing, setting time analysis, and wash resistance testing. The cytotoxicity was assessed using the MTT test, mineralization, and hemolysis. The characterization of the CHAC yielded results consistent with those reported in the literature, indicating decreased crystallinity peaks and increased solubility of the sample. However, the cement did not disintegrate when dissolved. Furthermore, it was demonstrated to possess hydrophilic properties and exhibited a pH that is suitable for its application in bone regeneration. During the biological experiments, CHAC exhibited enhanced cell viability and promoted mineralization, without inducing cell hemolysis. Carbonated hydroxyapatite-based cements shown encouraging outcomes in promoting bone regeneration and enhancing cell viability. The test findings indicate that the developed biomaterial created a conductive environment for bone regeneration.