Re-Engineering of Natural Apatite for Scaffold of Hard Tissues

Recent progresses in orthopedic medicine, traumatology and odontology have created a great requirement for biomaterials, especially those products having a composition based on calcium orthophosphate, which is similar to inorganic bone structure. Given this situation, there has been an intense search for new origins and resources of biomaterials. The natural occurring materials have been a focus of important studies because they can satisfy the great demand of biomaterials. Studies on these natural materials have reported interesting progresses in relation to the biological tissue regeneration for reparative medicine. In this research work, samples of minerals of a geological hydrothermal deposit were analyzed and this material has been proposed as an important resource of biomaterials. The minerals extracted were disaggregated, transformed into cylindrical specimens by Arc Plasma Sintering, and tested for biological compatibility. The mineralogy of the extracted material revealed a high content of phosphates in the form of apatite, followed by small amounts of other associated mineralogical species such as quartz and gypsum. Under these characteristics, the mineral powder showed a good disposition to sintering; being able to densify at temperatures above 1000ºC. The results of sintering were correlated with the different phase evolutions with the process temperatures; with apatite showing very good thermochemistry stability. Preliminary, biological "in vitro" tests of cells attachment and proliferation of human osteoblasts, MG63, indicated that, the prepared specimen sintered at 1200ºC appear to be quite promising, as it showed the best cell activation similar to the biological behavior of the reported commercial hydroxyapatite.

Hydrothermal Deposit; Natural Hydroxylapatite; SPS; Biocompatibility