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Titanium-based prosthetic implants are commonly used in Traumatology and Maxillofacial Surgery to achieve functional recovery of a severely damaged bones. Prosthetic replacements fail in the long term due to poor osseointegration, i.e. lack of chemical and structural bond between the metal and the surrounding bone tissue. Decorating the prostheses surface with specific molecular clues could promote a more favorable interaction of bone cells, leading to a better bone-metal integration. The RGD domain of fibronectin has been widely used in tissue engineering to decorate the surface of synthetic biomaterials, so as to promote a better cell-material interaction (1,2). Our objective was to assess if decorating the titanium surface with RGD domains would positively influence the relationship between bone cells and the metal surface of the prostheses, thus promoting a better osseointegration. Porous 3D scaffolds of Ti6AL4V ELI alloy were manufactured by Electron Beam Melting additive technology and decorated with RGD-tailored PAMAM dendrimers. Adhesion and proliferation of osteoprogenitor cells were monitored on both RGD-decorated and non-decorated controls. Our results suggest that the RGD-hemidendron provides a significantly more favorable molecular milieu to promote cell proliferation, thus accelerating the colonization of the prosthesis’ surface by bone cells. Therefore, the RGD-hemidendron coating might represent a promising strategy to improve prosthesis osseointegration. References: [1] “Extracellular matrix cell adhesion peptides: functional applications in orthopedic materials”, RG. LeBaron and KA. Athanasiou, Tissue Engineering Vol. 6, 85-103 (2000). [2] “RGD modified polymers: biomaterials for stimulated cell adhesion and beyond”, U. Hersel, C. Dahmen and H. Kessler, Biomaterials Vol. 24, 4385-4415 (2003) CIBER-BBN, Red Española de Terapia Celular (TerCel RD16/0011/0022); MINECO (BIO2015-66266-R); Junta de Andalucía (P11-CVI-7245, PI-0555-2013 y PI-0332-2016 CS)

Maxillary bone loss in commonly found in humans, due to bone ageing, tooth loos, periodontal disease and, more severely, to trauma, radiotherapy and tumor resection. Masillofacial reconstructive surgery is a still unmet clinical demand, available therapies include grafting of autologous or heterologous bone tissue and/or the implantation of metallic plates, buy these treatments are still unable to resume form and function. The emrgence of 3D-printing technology applied to metal alloys now allows the manufacturing of customized, patient-tailored prosthetic implants. However, poor bone quiality at the implant site due to ageing or disease still hamper proper osseointegration. By combining Electron Beam Melting metal sintering and tissue engineering, we are developing hybrid maxillofacial implants, wher a metal framework of Ti6Al4V alloy confers both and appropiaate shape and mechanical stabilty, while stem cells and osteogenic molecules stimulate bone growth into the metal framework, thus pormoting osseointegration. We hereby present the in vitro work driving to the development of our hybrid maxillofacial prostheses, as well as the setting up of an in vivo model of complete maxilla full resection, created in order to test the prostheses in a preclinical study Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.

1 página. XIV Congresos de la Sociedad Española de Biología Celular (Málaga, 12-15 de diciembre, 2011)., Among the most impeding conditions for a patient are those affecting the skeleton. Complex fractures, surgical removal of tumours, congenital malformations and other bone and joint diseases require the use of prosthesis and bone substitutes., This work was cofunded by projects BIO2009-13903-C02-01/01 (MICINN), P07-CVI-2781 (Junta de Andalucía), CIBER-BBN (intramural BIOGELANGIO), Red TerCel (Instituto de Salud Carlos III). CIBER-BBN is an initiative funded by the VI National R&D&i Plan 2008-2011, Iniciativa Ingenio 2010, Consolider Program, CIBER Actions and financed by the Instituto de Salud Carlos III with assistance from the European Regional Development Fund.

Despite the increasing use of transradial techniques for cardiac percutaneous procedures, none of the strategies commonly utilized for hemostasis has been able to reduce the occurrence of radial artery occlusion (RAO). The aim of this study was to evaluate the occurrence of 24-hour RAO and the rate of bleeding of a novel hemostatic device for radial closure after percutaneous interventions, in adjunct to short-time compression.Once the radial access was obtained, patients were randomized to 3 different strategies of radial closure: a short compression with the QuikClot® Interventional™ pad (Z-Medica Corporation, Wallingford, CT, USA) (15 minutes, group 1), a short compression (15 minutes, group 2), and a conventional prolonged compression (2 hours, group 3) both without QuikClot® utilization.Fifty patients in group 1, 20 in group 2, and 50 in group 3 were enrolled. The three groups were homogenous for baseline and procedural characteristics. None of patients in group 1 developed RAO, 1 (5%) occurred in group 2, and 5 (10%) in group 3 (P = 0.05). Active bleeding after compression removal occurred in 10 patients (20%) in group 1, 18 (90%) in group 2, and 1 (2%) in group 3 (P0.001). Among patients in group 1, at univariate analysis, the predictors of acute bleeding resulted in chronic therapy with clopidogrel (Odds Ratio 28.78, 95% Confidence Intervals 4.79-172.82, P0.001) and high levels of activated clotting time (ACT) at the time of sheath removal (OR 1.02, 95% CI 1.00-1.03, P = 0.009). At ROC analysis, the cutoff value of ACT for the risk of bleeding with a sensitivity of 80% and specificity of 75% was 287 seconds.Early sheet removal and short-time compression with QuikClot® Interventional™ can reduce the rate of RAO after diagnostic or interventional procedures especially in patients not on double antiplatelet therapy.

Osseointegration of metal prosthetic implants is a yet unresolved clinical need that depends on the interplay between the implant surface and bone cells. The lack of a relationship between bone cells and metal has traditionally been solved by coating the former with &ldquo, organic&rdquo, ceramics, such as hydroxyapatite. A novel approach is hereby presented, immobilizing covalently dendrimeric structures onto titanium implants. Amide-based amino terminal dendrons were synthetized and coupled to titanium surfaces in a versatile and controlled way. The dendritic moieties provide an excellent scaffold for the covalent immobilization of bioactive molecules, such as extracellular matrix (ECM) protein components or antibiotics. Herein, tripeptide arginine-glycine-aspartic acid (RGD) motifs were used to decorate the dendritic scaffolds and their influence on cell adhesion and proliferation processes was evaluated.