Piedad N de Aza studied Chemistry at the Autonoma University of Madrid and Ceramic at the Santiago de Compostela University where she received her doctoral degree in 1995. She did a postdoctoral stage at the IRC in Biomaterials at the Queen Mary & Wetsfield College, University of London (U.K.) working on in vitro and in vivo behavior of bioceramics. At this moment, she is the Chair of the Materials Science, Optic and Electronic Technology Department, Professor of Materials Science and Metallurgical Engineering and Researcher at the Bioengineering Institute at the Miguel Hernandez de Elche University.
The subsystem Nurse´s A-phase- silcocarnotite within the system Ca3(PO4)2–Ca2SiO4 was conducted as a preliminary step toward obtaining new biomaterials with controlled microstructures. The subsystem have been investigated, via annealing and quenching in the experimental method, direct observation of the phase composition of the resulting ceramics was studied by X-ray diffraction, differential thermal analysis and scanning electron microscopy with attached wavelength dispersive spectroscopy. The results showed that the sub-system presents an invariant eutectoid point at 1366 ±4°C with a composition of 59.5 wt% Ca3(PO4)2 and 40.5 wt% Ca2SiO4. These results are in disagreement with the previous reported data, which locate the invariant point at 1250±20ºC and a composition of 55 wt% Ca3(PO4)2 and 45wt% Ca2SiO4. In addition, cell attachment test showed that the new eutectoid material supported the mesenchymal stem cells adhesion and spreading, and the cells stablished close contact with the ceramic after 28 days of culture. These findings indicate that the new ceramic material with eutectoid microstructure of lamellae morphology possesses good bioactivity and biocompatibility and might be a promising bone implant material.
DDs. Granada University, Spain 1996 (Odontology),PhD. Murcia University, Spain 2009 (Implant Dentistry), MSc. Murcia University, Spain 2009 (Implantology and Biomaterials), MSc. Granada University, Spain 2011 (Animal Care and Research in Biomedical Sciences), MSc. Murcia University, Spain 2013 (Advanced Implantology), Research Assistant. International Cathedra of Research Implantology and Biomaterials. UCAM. San Antonio Catholic University of Murcia. More than 40 papers published in journals with JCR. Actually I´m doing my second Ph.D in (Biomaterials) in the Miguel Hernández University, Elche, Spain. 2008-First Prize, II International Congress of Bone Regeneration, Madrid, Spain. 2009-First Prize, III International Congress of Bone Regeneration, Madrid, Spain. 2010-First Prize, III National Meeting, Spanish Society of Oral Surgery. Zaragoza, Spain 2011-Special Award Doctorate in Dentistry from the University of Murcia. 2011-First Prize, Spanish Society of Oral Surgery (SECIB), Zaragoza, Spain. 2011-First Prize, IX National Meeting, Spanish Society of Oral surgery.
Some studies have demonstrated that osteointegration and degradation processes are influenced by physical and chemical properties of the material.The present study compares two hidroxyapatites (HAs) and how the physico-chemical properties like chemical composition and particle morphology influence the material performance in vivo. The biological behavior of both (HAs) was evaluated with a histomorphometric study of the newly forming bone and mineral degradation, in retrieved bone biopsies following maxillary sinus augmentation, in 10 clinical cases. The HAs were characterized thorough powder X-ray diffraction XDR analyses, gas pycnometry and scanning electron microscopy SEM. Quantitative analyses were made by an Electronic Dispersive X-ray Spectroscopy (EDX) system. Ten patients were selected who required bilateral sinus augmentation. Following elevation of the lateral sinus walls, one material was placed in the right sinus and the other in the left sinus, as determined by randomized choice. Nine months after sinus lifting, a trephine bone core was harvested from the previously elevated maxillary sinus and sent for histomorphometric analysis. The specimens were processed for observation under a scanning electron microscope with backscattered electron imaging (SEM-BSE). The X-ray diffraction showed that both HAs were composed of single phase HA. Both HAs are porous and exhibit intraparticle pores (35-60%) around 0,03 μm. The particles size range varied (250-1000μm). Strong differences were observed in term of crystallinity the HA (B) granules exhibit low crystallinity, crystal size is 732 nm, while (HA) A structure consisted of a highly crystallinity and the crystal size is 325nm. Scanning electron microscopy revealed that newly formed bone had become closely attached to both HAs. Histomorphometric measurements on the bone biopsies showed that for the HA (B), the newly formed bone represented (23.5±2.4%), residual graft material (25.1±2.3%) and for connective tissue (51.4±3.4%), while for the HA (A) newly formed bone (28.5±2.4%), residual graft material (31.3±2.3%) and non-mineralized connective tissue (40.2±3.4%). The HAs assessed in the study were shown to be biocompatible and osteoconductive when used for maxillary sinus elevation. The HA (A) was not complete resorbable material over the time period covered by this study. Despite the similar characteristics of the two HAs the differences found in terms of crystallinity may determine different behavior of this material. Detailed information about graft material characteristic is crucial to evaluate their clinical outcomes.