Influence of Hap incorporation and β- TCP in the wollastonite/brushite bone cement
ABSTRACT The high number of patients with health problems due to bone diseases or trauma has promoted the development of biomaterial research to ensure a better quality of life. Among the various biomaterials, polymeric (PMMA) or ceramic bone cements (phosphates and calcium silicates) stands out for such application. In view of the above, the objective of the research was to evaluate the incorporation of calcium phosphates (β-TCP (sample 1-A1) and hydroxyapatite-HAp (sample 2-A2) in the proportion of 2% (m/m) for the formation of calcium silicate bone cement (wollastonite / brushite) by the method of dissolution/precipitation. The powder mixture (wollastonite) was homogenized, subsequently a solution of phosphoric acid added to form the bone cement were placed in a teflon mold based on the ISO 5833 ABNT NBR standard, and finally left at 25ºC for 24 hours obtaining the specimens. XRD analysis of the samples indicated the presence of the crystalline phases of calcium phosphate (β-TCP and HAp) and calcium silicate (wollastonite and Brushite). The MEV images showed particle size wollastonite/brushite/HAp/β-TCP. A granulometric analysis was carried out from the micrographs, where it was observed that the incorporation of the phosphates influenced the agglomeration of the particle sizes when compared to the pure bone cement. The compression test indicates that the incorporation of the phosphates improves the compressive strength, due to the reduction of the particles which causes a greater compression. It is concluded that A2 with the incorporation of HAp this improvement of mechanical resistance was more intense in relation to A1, however the two samples had significant improvements in relation to calcium silicate bone cement.