Effect carboxymethylcellulose addition on the properties of wollastonite cement (CaSiO3) for Biomedical application

• Grant number: 20/02950-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: August 01, 2020
• End date: January 31, 2022
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Gilmar Patrocínio Thim
• Grantee: Letícia Terumi Kito
• Host Institution: Divisão de Ciências Fundamentais (IEF). Instituto Tecnológico de Aeronáutica (ITA). Ministério da Defesa (Brasil). São José dos Campos , SP, Brazil

Abstract

As human life expectancy increases and degenerative bone diseases become more common, especially in the elderly population, the necessity to develop synthetic biomaterials for bone repair and regeneration is becoming increasingly relevant. To solve such problems, different types of materials, as well as calcium silicates, have been studied as possible alternatives for use in the repair and replacement of hard tissues. Recent studies have shown that some calcium silicate ceramics, such as wollastonite (CaSiO3), have excellent biocompatibility, bioactivity and low toxicity. Therefore, CaSiO3 ceramics are promising candidates for applications in regenerative medicine. Calcium silicates can also be used as dental cement builders. These cements are formed by dissolving a calcium silicate in a phosphate solution, precipitating hydroxyapatite and a glassy silicate. It is known that after being injected, cement should be able to maintain its shape and withstand mechanical stress during this period. Therefore, an adequate setting time is essential for success during a surgical procedure. Studies show that the use of polymeric additives, such as carboxymethylcellulose, sodium alignate and sodium polyacrylate improve the injectability and the mechanical properties of cements without modifying the chemical reactions that occur during the curing of the cement. Therefore, this work aims to study the effect of the use of carboxymethylcellulose (CMC) on injectability, setting time, and mechanical strength of a calcium silicate (CaSiO3) cement. The wollastonite powder will be produced using the sol-gel methodology. CMC will be solubilized in a buffer solution, to which the wollastonite powder will be added later to form the cement. The resulting material will be evaluated for morphology using scanning electron microscopy and properties such as setting time, injectability and mechanical resistance to compression of the obtained cements.