Bioactividad y degradación de compuestos de wollastonita-poli (N-butil-2-cianoacrilato)

Abstract

Quick setting cements may be a promising alternative to metallic devices for immobilization of bone fragments in several maxillofacial surgical procedures. The aim of this study was the evaluation of bioactivity and degradation of wollastonite-poly(n-butyl-2-cyanoacrylate) composite biomaterials, just to be used as surgical cements. Three formulations were prepared by mixing n-butyl-2-cyanoacrylate with natural wollastonite-W, silanized wollastonite-Ws and wollastonite, coated with 5 % acetyl tributyl citrate-Wa. Raw materials and composites were characterized by means of X-ray diffraction, Fourier transform-infrared spectroscopy, thermal gravimetric analysis and scanning electron microscopy, coupled to energy dispersive X-ray analysis. Bioactivity was tested by immersion of the material into simulated body fluid (SBF) for 21. Hydrolytic degradation was studied in distilled water at 70 °C for 2, 7 and 30. The morphological and compositional analysis of material surfaces after SBF immersion tests showed a time dependent apatite nucleation and growth, typical of bioactive materials. The apatite layer formed on Wa-BCA after 21 of soaking in SBF was denser than those on W-BCA and Ws-BCA composites. The greater degradation observed for the Wa-BCA composite and the subsequent exposition of bioactive ceramics to the environment seems to be the reason for the increased bioactivity, in comparison to the other formulations tested behavior makes these biomateriales attractive to be used as bone cements.