Bionate biocompatibility: in vivo study in rabbits

Response to foreign materials includes local tissue reaction, osteolysis, implant loosening, and migration to lymph nodes and organs. Bionate 80A human explants show minor wear and slight local tissue reaction, but we do not know the response at the spinal cord, nerve roots, lymph nodes, or distant organs. This study aims to figure out reactions against Bionate 80A when implanted at the spinal epidural space of 24 20-week-old New Zealand white rabbits. In one group of 12 rabbits, we implanted Bionate 80A on the spinal epidural space, and another group of 12 rabbits was used as the control group. We studied tissues, organs, and tissue damage markers on blood biochemistry, urine tests, and necropsy. The animals' clinical parameters and weight showed no statistically significant differences. At 3 months, the basophils increased slightly in the implant group, platelets decreased in all, and at 6 months, implanted animals showed slight eosinophilia, but none of these changes was statistically significant. External, organ, and spinal tissue examination showed neither toxic reaction, inflammatory changes, or noticeable differences between groups or survival periods. Under microscopic examination, the Bionate 80A particles induced a chronic granulomatous response always outside the dura mater, with giant multinucleated cells holding phagocytized particles and no particle migration to lymph nodes or organs. Thus, it was concluded that Bionate particles, when implanted in the rabbit lumbar epidural space, do not generate a significant reaction limited to the surrounding soft tissues with giant multinucleated cells. In addition, the particles did not cross the dura mater or migrate to lymph nodes or organs

Bionate Lumbar Disc Nucleus Prosthesis : Biomechanical Studies in Cadaveric Human Spines

Design: cadaveric spine nucleus replacement study. Objective: determining Bionate 80A nucleus replacement biomechanics in cadaveric spines. Methods: in cold preserved spines, with ligaments and discs intact, and no muscles, L3-L4, L4-L5, and L5-S1 nucleus implantation was done. Differences between customized and overdimensioned implants were compared. Flexion, extension, lateral bending, and torsion were measured in the intact spine, nucleotomy, and nucleus implantation specimens. Increasing load or bending moment was applied four times at 2, 4, 6, and 8 Nm, twice in increasing mode and twice in decreasing mode. Spine motion was recorded using stereophotogrammetry. Expulsion tests: cyclic compression of 50-550 N for 50,000 cycles, increasing the load until there was extreme flexion, implant extrusion, or anatomical structure collapse. Subsidence tests were done by increasing the compression to 6000 N load. Results: nucleotomy increased the disc mobility, which remained unchanged for the adjacent upper level but increased for the lower adjacent one, particularly in lateral bending and torsion. Nucleus implantation, compared to nucleotomy, reduced disc mobility except in flexion-extension and torsion, but intact mobility was no longer recovered, with no effect on upper or lower adjacent segments. The overdimensioned implant, compared to the customized implant, provided equal or sometimes higher mobility. Lamina, facet joint, and annulus removal during nucleotomy caused more damaged than that restored by nucleus implantation. No implant extrusion was observed under compression loads of 925-1068 N as anatomical structures collapsed before. No subsidence or vertebral body fractures were observed under compression loads of 6697.8-6812.3 N. Conclusions: nucleotomized disc and L1-S1 mobility increased moderately after cadaveric spine nucleus implantation compared to the intact status, partly due to operative anatomical damage. Our implant had shallow expulsion and subsidence risks

Nucleus disc replacement : designs and material selection FEA analysis

Study design. Material selection, implant design and Finite Element Analysis (FEA) studies. Background. Nucleus disc replacements, implanted since 1960, have undergone continuous evolution in materials and designs, but subsidence, extrusion, and in vivo degradation limit widespread use. Aim: To create a new nucleus disc replacement that avoids the abovementioned drawbacks. Material and Methods. We created eighteen designs with varied materials and analyzed them with FEA in compression and shear tests in a lumbar spine model programmed in Ansys Parametric Design Language. Results. Bionate® 80A had the closest mechanical characteristics to the intact disc nucleus. Monobloc designs bore the physiological stresses correctly but suffered significant deformations with permanent damage during surgical insertion through the annulus opening. In addition, sandwich designs were too rigid and had an unreliable curing process. Therefore, we chose an oval doughnut-like 5 mm wall monobloc Bionate® 80A nucleus replacement. It minimized implant stress in loading, distributed the loads uniformly, and tolerated the lateral compression during implantation. Conclusions. Out of the eighteen designs we analyzed with FEA, we found that the monobloc oval doughnut-like Bionate 80A nucleus replacement reproduced best the biomechanics of the natural disc nucleus and had the lowest subsidence risk as it transmits the load to the ring apophysis. Furthermore, due to its elasticity implanting it through the average annulotomy required to perform a lumbar microdiscectomy should be possible

Barbed Dental Ti6Al4V Alloy Screw : Design and Bench Testing

Background context. Dental implants are designed to replace a missing tooth. Implant stability is vital to achieving osseointegration and successful implantation. Although there are many implants available on the market, there is room for improvement. Purpose. We describe a new dental implant with improved primary stability features. Study design. Lab bench test studies. Methods. We evaluated the new implant using static and flexion-compression fatigue tests with compression loads, 35 Ncm tightening torque, displacement control, 0.01 mm/s actuator movement speed, and 9-10 Hz load application frequency, obtaining a cyclic load diagram. We applied variable cyclic loadings of predetermined amplitude and recorded the number of cycles until failure. The test ended with implant failure (breakage or permanent deformation) or reaching five million cycles for each load. Results. Mean stiffness was 1151.13 ± 133.62 SD N/mm, mean elastic limit force 463.94 ± 75.03 SD N, and displacement 0.52 ± 0.04 SD mm, at failure force 663.21 ± 54.23 SD N and displacement 1.56 ± 0.18 SD mm, fatigue load limit 132.6 ± 10.4 N, and maximum bending moment 729.3 ± 69.43 mm/N. Conclusions. The implant fatigue limit is satisfactory for incisor and canine teeth and between the values for premolars and molars for healthy patients. The system exceeds five million cycles when subjected to a 132.60 N load, ensuring long-lasting life against loads below the fatigue limit

Criterios biomecánicos de diseño de un nuevo sistema de fijación externa: Stronger®

Se presenta el desarrollo de un nuevo sistema de fijación externa basado en estudios de investigación aplicada, cuyos resultados se han plasmado en criterios de diseño clínicos y biomecánicos. Los aspectos novedosos contemplados se refieren a un aumento de la rigidez del montaje en base a la fijación y el dentado de las rótulas de articulación. Asimismo, se facilita la técnica quirúrgica mediante el taladrado y colocación de las agujas sin la utilización de plantillas y la posibilidad de corregir desplazamientos en el foco fractuario de forma independiente en los tres planos del espacio. Finalmente, se ha diseñado un sistema de monitorización, acoplable al fijador, para caracterizar mecánicamente el callo de fractura durante el período de consolidación.A new external fixation system has been designed based on previous applied research studies. The design criteria generated were focused on both clinical and biomechanical aspects. An increase in frame stiffness was obtained by means of an independent fixation system of the pins, clamp sleeves and striated hinges. Furthermore, surgical technique has been simplified by means of independent adjustment in the three space planes of movement. The use of a previous guide fixator for drilling and pin insertion was eliminated. Finally, a strain gauge monitoring system has been developed to characterize mechanical callus features during fracture healing

ADDISC lumbar disc prosthesis : Analytical and FEA testing of novel implants

The intact intervertebral disc is a six-freedom degree elastic deformation structure with shock absorption. 'Ball-and-socket' TDR do not reproduce these properties inducing zygapophyseal joint overload. Elastomeric TDRs reproduce better normal disc kinematics, but repeated core deformation causes its degeneration. We aimed to create a new TDR (ADDISC) reproducing healthy disc features. We designed TDR, analyzed (Finite Element Analysis), and measured every 500,000 cycles for 10 million cycles of the flexion-extension, lateral bending, and axial rotation cyclic compression bench-testing. In the inlay case, we weighted it and measured its deformation. ADDISC has two semi-spherical articular surfaces, one rotation centre for flexion, another for extension, the third for lateral bending, and a polycarbonate urethane inlay providing shock absorption. The first contact is between PCU and metal surfaces. There is no metal-metal contact up to 2000 N, and CoCr28Mo6 absorbs the load. After 10 million cycles at 1.2-2.0 kN loads, wear 140.96 mg (35.50 mm3), but no implant failures. Our TDR has a physiological motion range due to its articular surfaces' shape and the PCU inlay bumpers, minimizing the facet joint overload. ADDISC mimics healthy disc biomechanics and Instantaneous Rotation Center, absorbs shock, reduces wear, and has excellent long-term endurance

Proteínas morfogenéticas óseas (BMPs): Efecto de la proteína osteogénica-1 (OP-l/BMP-7) en la condrogénesis y osteogenesis

En la actualidad, los estudios sobre biología molecular han facilitado el análisis de ciertos factores de transformación del crecimiento tipo ß(TGF-ß)I, entre los que destaca una familia de proteínas morfogenéticas óseas (BMPs). Las técnicas de ingeniería genética han permitido replicar alguno de estos factores y localizar los genes que codifican dichas proteínas. La proteína osteogenics-1 (OP-1) ha sido caracterizada y sintetizada in vitro y muestra un elevado potencial osteogénico y condrogénico tanto in vivo como in vitro. Se presenta una revisión de los últimos avances en la aplicación experimental de las BMPs, y especialmente de la OP-1, en el área de la Cirugía Ortopédica y la TraumatologíaNowadays, molecular biology studies have promoted the bone morphogenetic proteins (BMPs) analysis. These multifunctional proteins are structurally related to transforming growth factor-6 (TGF-6). Genetic engineering techniques have allowed to sequence some of these BMPs. It has been characterized the expression and processing of osteogenic protein-1 (OP-1), a bone morphogenetic protein of the TGF-6 family. The OP-1 shows a high osteogenic and chondrogenic potential. The aim of this paper is to review some updated advances of the BMPs experimental applications, particularly OP-1, in relation to Orthopaedic Surgery and Traumatolog

Development of a new methodology for articular cartilage’s mechanical evaluation

El Instituto de Biomecánica de Valencia (IBV) ha desarrollado y puesto en práctica una nueva metodología para la evaluación mecánica de cartílago articular. El protocolo diseñado ha permitido comparar las características mecánicas del cartílago articular sano con las del cartílago tratado con plasma rico en factores de crecimiento y con suero salino fisiológico.Instituto de Biomecánica de Valencia (IBV) developed and updated a new method for assessing the biomechanical properties of knee articular cartilage. The designed protocol has allowed to compare mechanical behaviour of healthy cartilage with articular cartilage treated by plasma rich in growth factors and physiological saline serum.Veterinari

Nasal mask for the sleep apnea

[EN] GASMEDI, who supplies home delivered respiratory therapies, has developed in collaboration with Biomechanics Institute of Valencia a new nasal mask for the treatment of the sleep apnea disease. To this end, the person oriented innovation model has been adopted, specially focused on the elderly population. The application of such innovation model has made possible the development of a nasal mask that overcomes the usability and injury drawbacks of current masks. Besides, the nasal mask has been designed in such a way that can be easily used by the aged people.[ES] La empresa GASMEDI, proveedora asal para la apnea del sueño de terapias respiratorias a domicilio, ha desarrollado, en colaboración con el Instituto de Biomecánica (IBV), una nueva mascarilla para el tratamiento de la apnea del sueño. Para su desarrollo se ha seguido el modelo de innovación orientada por las personas, prestando especial atención a las personas de edad avanzada. La aplicación de dicho modelo de innovación perseguía superar los problemas de usabilidad y lesiones que presentan las mascarillas nasales actuales. Asimismo, la mascarilla se ha diseñado de forma que sea fácilmente utilizable por personas mayores.Proyecot desarrollado a través del II Plan de Competitividad de la Empresa Valenciana (PCEV) de IMPIVA, cofinanciado por los fondos FEDER, dentro del Programa Operativo FEDER de la Comunitat Valenciana 2007-2013.Morales Martín, I.; Atienza Vicente, CM.; Villuendas Ros, A.; Carmona Gutiérrez, C.; Vidal Calvo, L.; Nacher Fernandez, B.; Navarro Garcia, FJ.... (2013). Mascarilla nasal para la apnea del sueño. Revista de biomecánica. 59:51-53. http://hdl.handle.net/10251/38678S51535

The European Reference Genome Atlas: piloting a decentralised approach to equitable biodiversity genomics.

ABSTRACT: A global genome database of all of Earth’s species diversity could be a treasure trove of scientific discoveries. However, regardless of the major advances in genome sequencing technologies, only a tiny fraction of species have genomic information available. To contribute to a more complete planetary genomic database, scientists and institutions across the world have united under the Earth BioGenome Project (EBP), which plans to sequence and assemble high-quality reference genomes for all ∼1.5 million recognized eukaryotic species through a stepwise phased approach. As the initiative transitions into Phase II, where 150,000 species are to be sequenced in just four years, worldwide participation in the project will be fundamental to success. As the European node of the EBP, the European Reference Genome Atlas (ERGA) seeks to implement a new decentralised, accessible, equitable and inclusive model for producing high-quality reference genomes, which will inform EBP as it scales. To embark on this mission, ERGA launched a Pilot Project to establish a network across Europe to develop and test the first infrastructure of its kind for the coordinated and distributed reference genome production on 98 European eukaryotic species from sample providers across 33 European countries. Here we outline the process and challenges faced during the development of a pilot infrastructure for the production of reference genome resources, and explore the effectiveness of this approach in terms of high-quality reference genome production, considering also equity and inclusion. The outcomes and lessons learned during this pilot provide a solid foundation for ERGA while offering key learnings to other transnational and national genomic resource projects.info:eu-repo/semantics/publishedVersio