A Critical Comparison on Biocompatibility of Different Phases of Sol-Gel Derived Calcium Phosphates as Bone Graft Materials

Calcium Phosphate cement has been the subject of intense investigation over the past few years. This study compares difference in biocompatibility between the three main phases of Ca-P, namely Hydroxyapatite, Dicalcium phosphate and beta-Tricalcium phosphate. It involves composite preparation followed by cell test. Material parameters were stoichiometry (Hydroxyapatite with Ca-P ratio of 1.67, Dicalcium phosphate with Ca-P ratio of 1.0, beta-Tricalcium phosphate with Ca-P ratio of 1.50) and crystallographic structure and arrangement. The composites in concern were produced by mixing PVA (polyvinyl alcohol) and Ca-P in equal fraction. Cell test was performed for 24 h and 7 days. Biocompatibility analysis was performed both qualitatively and quantitatively. XRD, FTIR, SEM and TEM were used to analyse the materials at various stages of the research. All calcium phosphate composites were biocompatible with cells. Hydroxyapatite ceramic expressed highest biocompatibility followed by Dicalcium phosphate and beta-Tricalcium phosphate after 24 h cell test, whereas, after the 7-days test biocompatibility of Dicalcium phosphate was comparable to Hydroxyapatite. This study shows that Dicalcium phosphate is a better alternative to Hydroxyapatite, where biodegradation is crucial for patients' recovery.