Hydroxyapatite coating on silicon nitride surfaces using the biomimetic method

Abstract

Silicon nitride based ceramics are promising candidates for biomedical applications due to their chemical and dimensional stability associated to suitable mechanical strength and relatively high fracture toughness. However, the bioinert characteristics of these ceramics limit their application to situations where the formation of chemical bonds between the material and the tissue are not essential. A way to broaden the application field of these ceramics in medicine is promoting their bioactivity by means of a hydroxyapatite coating. Therefore, in this paper, samples of silicon nitride were coated with apatite using the biomimetic method. The treated silicon nitride surface was characterized by diffuse reflectance infrared Fourier transformed, X ray diffraction and scanning electron microscopy. The results showed that a layer of hydroxyapatite could be deposited by this method on silicon nitride samples surface.

Silicon nitride enhances osteoprogenitor cell growth and differentiation via increased surface energy and formation of amide and nanocrystalline HA for craniofacial reconstruction

“…Furthermore, the observed bands at 1,420–1465 and 875 cm −1 were attributed to the CO 2 3− group that substituted for the phosphate group in the apatite structure. These spectra are in agreement with other published data of the HA(Deng et al, ; Jia et al, ; Sanosh, Chu, Balakrishnan, Kim, & Cho, ; , & Bressiani, 2; Son et al, ). Of all the samples, only Si 3 N 4 showed a weak broadband at 1600–1650 cm −1 corresponding to the N‐H of amide I, which can explain the presence of amide peaks found in the Raman spectra.…”

Improving the Radiopacity of Calcium Aluminate Cement Based Blends

“…By this method, a bone-like apatite surface can be produced in an acellular SBF, where the ions present are similar to those of the inorganic compounds of human blood plasma. Two steps are involved in the process: i) nucleation and ii) precipitation and growth of the apatite layer 23 . Scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX) of compositions' samples without treatment in SBF are shown in Figure 3.…”

“…The Si-OH groups, formed by the adsorption of the SS solution ions on the ceramic surface, induce the apatite nucleation. After that, its growth is spontaneous as a consequence of subsequent depositions of calcium and phosphates ions that are present in the solution 23 . These results indicated the affinity of the hydroxyapatite precipitates with CAC-based ceramic, suggesting that the compositions studied have suitable surface features to become bioactive having excellent interaction with living tissues.…”

Aluminatos de cálcio e seu potencial para aplicação em endodontia e ortopedia

“…[ Table I procedimentos descritos [13,14], como apresentado nas Tabelas II e III, respectivamente. A solução de Kokubo foi preparada utilizando-se uma quantidade dos reagentes a fim de reproduzir a concentração de íons (mM) inorgânicos presentes no plasma humano (SBF 1) ou em uma proporção 1,5 vezes superior (SBF 1,5) a fim de acelerar a formação de apatita.…”

“…De acordo com a literatura, a formação de apatita pode explicar a biocompatibilidade deste material [18,19]. O SBF é uma solução simuladora do fluido corporal com concentrações inorgânicas similares ao do fluido extracelular humano, sendo uma solução metaestável contendo íons de cálcio e fosfato supersaturados, a fim de reproduzir a formação de apatita [13,14]. Os íons Ca 2+ liberados do MTA são pouco solúveis em fluidos biológicos Tempo (dia) resultando na precipitação de hidroxiapatita (HA) [19].…”