Obtenção de biocimentos de hidroxiapatita e β-TCP para aplicações ortopédicas e odontológicas.

• Autor(a) principal: Silva, Cristiane Maria Pereira da
• Data de Publicação: 2019
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Ceará (UFC)
• Texto Completo: http://www.repositorio.ufc.br/handle/riufc/48630
• topic: Biocimento; Hidroxiapatita; β-TCP; Fosfato de cálcio; Citotoxicidade

The use of autogenous grafts for bone repair is considered the "gold standard". However, it has some limitations related to increased morbidity, pain, infection, and the sacrifice of health tissues. To overcome this limitations, the development of synthetic bone grafts, such as calcium phosphate biocements (BFC), has cathy the attention of scientists. Many studies cited excellent performances of the hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) bioceramics. However, the researchs and developments of HA and β-TCP BFC are still recent, therefore, an investigation of their properties and new methods of development are desirable. In this work, two BFC were obtained from different methods, aiming to meet both the needs of dentistry and orthopedics. The first (BFC I) had its solid phase synthesized by solid state and its liquid phase was a 4% Na2HPO4 solution. The solid phase diffractogram demonstrated that it was possible to obtain biphasics β-TCP/HA bioceramics by solid-state reaction, which is interesting since it is a simple and inexpensive method. An analysis of the BFC I diffractogram confirmed that the biocement has the two phases HA and β-TCP. Concerning the setting time and pH, respectively, BFC I has an initial setting time of 6 minutes and a final setting time of 20 minutes and the pH equal to 7.6. BFC I’s setting time is limited to some orthopedic applications, so a change in methodology has been necessary. Thus, the second biocement (BFC II), had its solid phase by the precipitation in aqueous solution and sol-gel and its liquid phase was composed of a solution of 2 M H3PO4 and sodium pyrophosphate. An analysis of the BFC II diffractogram confirmed the HA and β-TCP phases, but the monetite phase occurred. Concerning the setting time and pH, respectively, it has an initial setting time of 3 minutes and a final setting time of 7 minutes, the pH was equal to 7.0. In vitro cytotoxicity of BFC I was analyzed by the sulfurrodamine B (SRB) method in direct contact with murine fibroblasts L929 strain. BFC II was analyzed by its extract in contact with murine osteoblast OFCOL II by the Alamar Blue method. The two cytotoxicity tests showed that BFC I and II are not cytotoxic. Although preliminary, the physicochemical characterization and the absence of cytotoxicity indicate that the BFCs obtained are promising materials for orthopedics and dentistry applications.