Crystallization processes at the surface of polylactic acid—bioactive glass composites during immersion in simulated body fluid

Abstract

We report on the crystallization processes occurring at the surface of PDLLA-Bioglass® composites immersed in simulated body fluid. Composites manufactured by injection molding and containing different amounts (0, 20, 30, and 50 wt %) of 45S5 Bioglass® particles were tested for durations up to 56 days and compared with Bioglass® particles alone. Crystallization processes were followed by visual inspection, X-ray diffraction (with Rietveld analysis) and scanning electron microscopy. Both calcite and hydroxyapatite were formed at the surface of all materials, but their relative ratio was dependent on the Bioglass® content and immersion time. Hydroxyapatite was always the major phase after sufficient immersion time, insuring bioactivity of such composites especially for Bioglass® content higher than 30 wt %. A scenario of crystallization is proposed. Rapid degradation of the composites with 50 wt % was also observed during immersion. Therefore, composites with 30 wt % of Bioglass® particles seem to exhibit the best balance between bioactivity and stability at least during the first weeks of immersion in contact with body fluids.

In vitro and in vivo evaluation of a polylactic acid‐bioactive glass composite for bone fixation devices

“…According to these results and the previous study about the in vitro “bioactivity” properties of these composites (showing that 20 wt % of Bioglass® was not sufficient to trigger bioactivity and that 50 wt % was already questioned because of a rapid degradation in SBF), the composite C30 was chosen for the next part of this work.…”

“…Choice of a preferred composite composition Despite a better in vitro "bioactivity" of the composite C50 described in a previous study, 31 this material has been dismissed for the next part of this work because of its apparent lower cytocompatibility and also because our previous work showed a strong visual degradation during bioactivity tests, only after few days. In the same way, the composite C20 presents the better cytocompatibility but the least bioactivity.…”

“…In a previous work, we showed that 45S5 Bioglass® particles in a P(L,DL)LA matrix induced hydroxyapatite precipitation when immersed in simulated body fluid (SBF). The thick layer of HA at the surface of composites containing 30 and 50 wt % of Bioglass® gave optimal conditions for bioactivity.…”

Exploring Innovative Approaches and Patient-Centered Outcomes From Positive Outliers in Childhood Obesity

“…19-21 Efforts to improve clinician-parent communication regarding weight status have been successful. 22 However, our study results indicate that parents may dismiss the applicability of growth charts and percentiles to their own children.…”

Mechanical characteristic and biological behaviour of implanted and restorative bioglasses used in medicine and dentistry: A systematic review

“…-Ag and Sr substituted bioactive glass for the investigation of antibacterial effects [19,20]; -Focused on cells growth, proliferation and protein interactions [21][22][23][24][25][26][27]; -Studies evaluating only the bioactivity and hydroxyl apatite (HA) formation [28][29][30][31][32][33][34]; -General characterization and synthesis of bioglass powders [35,36]; -Mechanical properties of a bioactive ceramic ␤-TCP [37].…”