New Generation Of Implants Research Articles

Implantation of In Situ Gelling Systems for the Delivery of Chemotherapeutic Agents.

Implantation is a modern method of administering chemotherapeutic agents, with a highly targeted effect and better patient tolerance due to the low frequency of administration. Implants are capable of controlled release, which makes them a viable alternative to infusional chemotherapy, allowing patients to enjoy a better quality of life without the need for prolonged hospitalization. Compared to subcutaneous implantation, intratumoral implantation has a number of significant advantages in terms of targeting and side effects, but this area of chemotherapy is still poorly understood in terms of clinical trials. At the same time, there are more known developments of drugs in the form of implants and injections for intratumoral administration. The disadvantages of classical intratumoral implants are the need for surgical intervention to install the system and the increased risk of tumor rupture noted by some specialists. The new generation of implants are in situ implants-systems formed in the tumor due to a phase transition (sol-gel transition) under the influence of various stimuli. Among this systems some are highly selective for a certain type of malignant neoplasm. Such systems are injected and have all the advantages of intratumoral injections, but due to the phase transition occurring in situ, they form depot forms that allow the long-term release of chemotherapeutic agents.

In Vivo Bone Progression in and around Lattice Implants Additively Manufactured with a New Titanium Alloy

The osseointegration in/around additively manufactured (AM) lattice structures of a new titanium alloy, Ti–19Nb–14Zr, was evaluated. Different lattices with increasingly high sidewalls gradually closing them were manufactured and implanted in sheep. After removal, the bone–interface implant (BII) and bone–implant contact (BIC) were studied from 3D X-ray computed tomography images. Measured BII of less than 10 µm and BIC of 95% are evidence of excellent osseointegration. Since AM naturally leads to a high-roughness surface finish, the wettability of the implant is increased. The new alloy possesses an increased affinity to the bone. The lattice provides crevices in which the biological tissue can jump in and cling. The combination of these factors is pushing ossification beyond its natural limits. Therefore, the quality and speed of the ossification and osseointegration in/around these Ti–19Nb–14Zr laterally closed lattice implants open the possibility of bone spline key of prostheses. This enables the stabilization of the implant into the bone while keeping the possibility of punctual hooks allowing the implant to be removed more easily if required. Thus, this new titanium alloy and such laterally closed lattice structures are appropriate candidates to be implemented in a new generation of implants.

POSSIBILITIES OF ENDOPROSTHETICS IN PATIENTS WITH THE CONSEQUENCES OF SHOULDER JOINT INJURIES

The use of shoulder joint replacement has increased significantly since the early 2000s. The method, initially used as the gold standard for the treatment of osteoarthritis, has long gone beyond the generally accepted indications, expanding its use for the treatment of shoulder joint injuries and their consequences. The new generation of implants has led to improved outcomes such as functionality, range of motion in the shoulder joint and patient satisfaction. The decision to perform anatomical endoprosthetics (hemiarthroplasty, total shoulder joint replacement) depends on the degree of osteopenia, the viability of the humerus head, the integrity of the tubercles or the functional state of the rotator cuff of the shoulder. This type of arthroplasty remains for patients with a functional rotator cuff. Reversible endoprosthetics is today the preferred treatment option for non-fusion or improper fusion of the proximal humerus with a collapse of the humerus head or a non-functioning rotator cuff. Despite the limitations and complications reported in the literature, revision arthroplasty has a good potential for functional improvement in patients with the consequences of injuries of the proximal humerus. This is a group of patients, which is a difficult task for a surgeon. As further research is carried out, implant designs and their clinical application will continue to evolve.

Additive manufacturing of biomimetic Titanium-Tantalum lattices for biomedical implant applications

Although additively manufactured titanium-tantalum alloys can offer unique mechanical and biological advantages for implant applications, their use in conjunction with engineered lattice architectures is yet to be explored. In the present study, the promising gyroid, diamond and Schwarz primitive minimal surfaces are used for the design of 3D lattices for biomedical implants. The lattices are fabricated using laser powder-bed fusion and a blend of elemental titanium-tantalum powder. The processability, compressive mechanical properties and in vitro biological properties of the dense and lattice samples are assessed via non-destructive and destructive characterization methods. The topologies from the designed structures are retained through processing and the compressive tests results show that the strength-to-modulus ratios are comparable to the conventional Ti-6Al-4 V alloy. However, the higher ductility and absence of toxic elements make the Ti-25Ta lattices a more favourable option for a new generation of implants. Compared to conventional lattices, the designs presented here also show advantageous mechanical properties for use in bone implants with higher elastic admissible strains. The in vitro cell cultures confirm the high biocompatibility of the material and improved biological response of the interconnected lattices over dense material.

Managing the severely atrophic maxilla: Farewell to zygomatic implants and extensive augmentations?

Background: Dental rehabilitation of severe atrophic upper jaws remains challenging. A new generation of subperiosteally placed and rigid multi-vector bone-anchored patient-specific implants proposes an innovative line extension in implant dentistry. This single-center retrospective study focused on treating severely atrophic maxillae using these implants.Methods: All patients who were treated with a patient-specific implant (IPS Implant® Preprosthetic, KLS-Martin, Tuttlingen, Germany) at Hannover Medical School due to severe atrophy of the maxilla who had no history of malignancy, cleft lip or palate, or trauma were evaluated regarding implant stability and prosthetic restoration, as well as complications.Results: Out of a total of 58 inserted implants, 13 implants in 10 patients, which were placed to treat a severely atrophic upper jaw, were identified. The mean follow-up period was 8.2 months (1–29 months). All implants were clinically stable over the entire period. All patients with an observation period of over 2 months received prosthetics for restoration. Minor complications, screw fractures, infection, and exposure of the framework were observed, but these did not lead to failure.Conclusion: This initial follow-up suggests that this new generation of implants represents a valuable treatment alternative, especially for patients with a history of failed dental implant placement. Larger numbers of cases and longer observation periods are required to confirm our findings.

Novel Biocompatible Ultrananocrystalline Diamond Coating Technology for a New Generation of Medical Implants, Devices, and Scaffolds for Developmental Biology

A new biomaterial paradigm for a new generation of implantable medical devices, prostheses, and scaffolds for stem cells growth and differentiation for developmental biology is provided by a novel multifunctional/biocompatible/body fluid corrosion-resistant ultra-nanocrystalline diamond (UNCD) film developed and patented in recent years. The UNCD coating provides a unique combination of multi functionalities, including biocompatibility, bioinertnes to chemical attack by body fluids, and surface chemistry, based on Carbon (C) atoms (element of life), to enable a new generation of implantable medical devices, prostheses, and scaffolds for tissue engineering, to impact the quality of life of people. This review article includes the following topics: 1) Brief description of the synthesis and properties of UNCD films and comparison with other diamond film technologies. 2) Brief description of key medical devices and prostheses under development, based on UNCD coatings. 3) Demonstration of UNCD as an outstanding scaffold for growing stem cells and induces differentiation for developmental biology, to treat specific medical conditions.Topics discussed include: • UNCD-coated microchip (artificial retina) is implantable on the eye’s retina to restore partial vision to people. Who are blind by retinitis pigmentosa, produced by genetically induced degeneration of the retina photoreceptors (The Argus II device, developed by a team of researchers and doctors from universities, national laboratories and the second Sight was currently implanted commercially in the USA and Europe,and it was selected by TIME magazine as one of the top 25 inventions for 2013). • UNCD- coated intraocular device for the treatment of glaucoma (intraocular pressure associated optical neuropathy that could lead to blindness). • UNCD-coated metal dental implants with order of magnitudelonger life and superior performance than current implants. • UNCD- coated prostheses (hips, knees and other metal-basedimplants); • New generation of Li-ion batteries (LIBs) for defibrillator/ pacemakers, with ≥ 10 × longer life and safer than current LIBs. • Description of UNCD-based scaffolds

Cochlear Implant Strategies and Biomaterials from Past to Future

The cochlear implant (C.I.) is a neurobionic prosthesis, being one of the greatest achievements of auditory neuroscience. Although C.I. represents the gold standard in the treatment of deafness in both the child and the adult, some problems like perception of speech in noise (atmosphere, environment), perception of music, binaural hearing remain, aspect to which improvements are expected. The article (this review) revises the road from the first attempts to cochlear implantation to today�s modern and reliable cochlear implant. Continuous improvement of existing technology both in terms of biomaterials used and in terms of speech processing and simultaneous stimulation strategies, promise with certainty the introduction of C.I. with superior performance. A look in the future is through new ideas and techniques, which await the transition from the experimental to the clinical stage in the emergence of a new generation of implants.

Biomechanical properties of 3D-printed bone scaffolds are improved by treatment with CRFP

BackgroundOne of the major challenges in orthopedics is to develop implants that overcome current postoperative problems such as osteointegration, proper load bearing, and stress shielding. Current implant techniques such as allografts or endoprostheses never reach full bone integration, and the risk of fracture due to stress shielding is a major concern. To overcome this, a novel technique of reverse engineering to create artificial scaffolds was designed and tested. The purpose of the study is to create a new generation of implants that are both biocompatible and biomimetic.Methods3D-printed scaffolds based on physiological trabecular bone patterning were printed. MC3T3 cells were cultured on these scaffolds in osteogenic media, with and without the addition of Calcitonin Receptor Fragment Peptide (CRFP) in order to assess bone formation on the surfaces of the scaffolds. Integrity of these cell-seeded bone-coated scaffolds was tested for their mechanical strength.ResultsThe results show that cellular proliferation and bone matrix formation are both supported by our 3D-printed scaffolds. The mechanical strength of the scaffolds was enhanced by trabecular patterning in the order of 20% for compression strength and 60% for compressive modulus. Furthermore, cell-seeded trabecular scaffolds modulus increased fourfold when treated with CRFP.ConclusionUpon mineralization, the cell-seeded trabecular implants treated with osteo-inductive agents and pretreated with CRFP showed a significant increase in the compressive modulus. This work will lead to creating 3D structures that can be used in the replacement of not only bone segments, but entire bones.

Toward a new generation of pelvic floor implants with electrospun nanofibrous matrices: A feasibility study.

The use of knitted, polypropylene meshes for the surgical treatment of pelvic organ prolapse (POP) is frequently accompanied by severe complications. Looking for alternatives, we studied the potential of three different electrospun matrices in supporting the adhesion, proliferation, and matrix deposition of POP and non-POP fibroblasts, the most important cells to produce extracellular matrix (ECM), in vitro. We electrospun three commonly used medical materials: nylon; poly (lactide-co-glycolide) blended with poly-caprolactone (PLGA/PCL); and poly-caprolactone blended with gelatin (PCL/Gelatin). The matrices were characterized for their microstructure, hydrophilicity, and mechanical properties. We seeded POP and non-POP fibroblasts from patients with POP and we determined cellular responses and ECM deposition. All matrices had >65% porosity, homogenous microstructures, and close to sufficient tensile strength for pelvic floor repair: 15.4 ± 3.3 MPa for Nylon; 12.4 ± 1.6 MPa for PLGA/PCL; and 3.5 ± 0.9 MPa for PCL/Gelatin. Both the POP and non-POP cells adhered to the electrospun matrices; they proliferated well and produced ample ECM. Overall, the best in vitro performance appeared to be on nylon, presumably because this was the most hydrophilic material with the thinnest fibers. Electrospun nanofibrous matrices show feasible mechanical strength and great biocompatibility for POP and non-POP fibroblasts to produce their ECM in vitro and, thus, may be candidates for a new generation of implants for pelvic floor repair. Further studies on electrospun nanofibrous matrices should focus on mechanical and immunological conditions that would be presented in vivo. Neurourol. Urodynam. 36:565-573, 2017. © 2016 Wiley Periodicals, Inc.

Synthetic and degradable patches: an emerging solution for rotator cuff repair

The use of rotator cuff augmentation has increased dramatically over the last 10years in response to the high rate of failure observed after non-augmented surgery. However, although augmentations have been shown to reduce shoulder pain, there is no consensus or clear guideline as to what is the safest or most efficacious material. Current augmentations, either available commercially or in development, can be classified into three categories: non-degradable structures, extra cellular matrix (ECM)-based patches and degradable synthetic scaffolds. Non-degradable structures have excellent mechanical properties, but can cause problems of infection and loss of integrity in the long-term. ECM-based patches usually demonstrate excellent biological properties in vitro, but studies have highlighted complications in vivo due to poor mechanical support and to infection or inflammation. Degradable synthetic scaffolds represent the new generation of implants. It is proposed that a combination of good mechanical properties, active promotion of biological healing, low infection risk and bio-absorption are the ideal characteristics of an augmentation material. Among the materials with these features, those processed by electrospinning have shown great promis. However, their clinical effectiveness has yet to be proven and well conducted clinical trials are urgently required.

Novel doped hydroxyapatite thin films obtained by pulsed laser deposition

We report on the synthesis of novel ovine and bovine derived hydroxyapatite thin films on titanium substrates by pulsed laser deposition for a new generation of implants. The calcination treatment applied to produce the hydroxyapatite powders from ovine/bovine bones was intended to induce crystallization and to prohibit the transmission of diseases.The deposited films were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and energy dispersive X-ray spectroscopy. Pull-off adherence and profilometry measurements were also carried out.X-ray diffraction ascertained the polycrystalline hydroxyapatite nature of the powders and films. Fourier transform infrared spectroscopy evidenced the vibrational bands characteristic to a hydroxyapatite material slightly carbonated. The micrographs of the films showed a uniform distribution of spheroidal particulates with a mean diameter of ∼2μm. Pull-off measurements demonstrated excellent bonding strength values between the hydroxyapatite films and the titanium substrates.Because of their physical–chemical properties and low cost fabrication from renewable resources, we think that these new coating materials could be considered as a prospective competitor to synthetic hydroxyapatite used for implantology applications.

Orthopedic implants from bioactive rosette nanotubes/poly(2-hydroxyethyl methacrylate)/nano-hydroxyapatite composites

ABSTRACTWith multifunctionality and nanoscale dimensions, self-assembled rosette nanotubes (RNTs) exhibit unique biological and mechanical properties, making them promising to serve as a new generation of implants. Synthetic twin G^C base features the hydrogen bonding arrays of both guanine and cytosine and has the ability to self-organize spontaneously into nanotubes with a 3.5 nm outer diameter, a 1.1 nm inner channel running the length of the nanotube which can reach several micrometers in length. In this study, a twin G^C motif functionalized with an aminobutyl side chain (referred to as TBL) was synthesized, assembled into bioactive RNTs and used along with poly(2-hydroxyethyl methacrylate) (pHEMA) and hydroxyapatite (HA) nanoparticles to prepare RNTs/HA/pHEMA composites for orthopedic applications. The properties of these composites was investigated, notably the solidification process, surface morphology, mechanical properties, and cytocompatibility properties. The RNTs assembled from TBL and HA nanoparticles were found to be effective towards increasing the bioactivity of the composites thus establishing the potential of TBL/HA/pHEMA composites as very promising injectable orthopedic implant materials.

Bone microenvironment associated to wear debris in temporomandibular joint implants: pre-clinical model in mice

Aseptic osteolysis is a main cause of loosening of orthopaedic implant failures. The wear debris derived from polymers (UHWMPE) and/or metals of implants (Ti) elicit primary inflammatory and secondary osteolytic responses. In total temporomandibular joint (TMJ) reconstruction with implants, foreign body reactions are reported and are the major cause of failure in the metal-on-metal and Teflon® or Proplast®-on-metal prosthesis, leading a revision surgery. A new generation of implants replaced Teflon® by UHWMPE in the fossa component with acceptable clinical results in long term follow-up (14 years).

Thirty years of experience with alumina-on-alumina bearings in total hip arthroplasty

Alumina-on-alumina bearings in total hip arthroplasty have been developed in an attempt to minimise debris and the occurrence of osteolytic lesions. The outstanding tribological properties of this bearing system are explained by low surface roughness, high hardness for major scratch resistance, and high wettability. Since the 1970s, technological improvements in the manufacturing process of alumina components together with a better understanding of Morse taper technology have provided a surgical grade material with high density, high purity and small grains. Published studies on the outcome of total hip arthroplasty performed with this new generation of implants showed high survivorship especially in young and active patients, with survival rates free of revision of 90.8% to 97.4% at tenyears. However, concern remains over ceramic liner fracture and squeaking, which has been noted recently with increasing prevalence. This review will discuss the current knowledge on the use of alumina-on-alumina bearings.

Second generation locked plating of proximal humerus fractures—A prospective multicentre observational study

Surgical treatment of most displaced proximal humerus fractures is challenging due to osteoporosis. Locking plates are intended to provide superior mechanical stability. In a prospective multicentre study 131 patients were treated with second generation locked plating (NCB-PH, Zimmer, Inc.). The open procedure (n = 78) was performed using a deltopectoral approach; the minimally invasive technique (n = 53) involved percutaneous reduction and an anterolateral deltoid split approach. Clinical and radiological follow-up was obtained. Improvement in function (ROM) was statistically significant. Fracture type (AO) had the most significant impact on the incidence of complications. The most frequent complications detected were intra-articular screw perforation (15%) and secondary displacement (8%). Complication rate and functional outcome of the NCB-PH are comparable to reports in the literature. Not all problems are likely to be solved by this new generation of implants, i.e. secondary dislocation still occurred in 8% of our patients.

History and evolution in total ankle arthroplasty

The current study provides an overview of history and evolution in total ankle arthroplasty. We conducted a comprehensive literature search without limitations to language. Information from any source, providing evidence of the use ankle of prostheses (e.g. biomechanical testing, cadaveric implantations or clinical use) was evaluated. Data regarding biomechanical concepts, design considerations, published results (patient numbers, surgical method, follow-up, complications and survival rates) were collected. Only level IV studies were found. Mobile-bearing prostheses are mainly used in Europe, and fixed-bearing implants are mainly used in the USA. The current designs' failure rate is 10-12% at approximately 5 years. Survival rates vary among different institutions. Increased surgeons' experience is associated with better outcomes. Biomechanical studies and review of previous implant failures has led to the development of a new generation of implants. Results show that ankle arthroplasty is a viable alternative for the management of ankle arthritis in selected patients.

The design and production of Ti-6Al-4V ELI customized dental implants

This paper addresses the production of customized Ti-6Al-4V ELI dental implants via electron beam melting (EBM). The melting of Ti-6Al-4V ELI powder produces implants with great biocompatibility, fi ne mechanical performance, and a high bone ingrowth potential. The EBM technology is used to produce one-component dental implants that mimic the exact shape of the patient’s tooth, replacing the traditional, three-component, “screw-like” standardized dental implants currently used. The new generation of implants provides the possibility of simplifying pre-insertion procedures leading to faster healing time, and the potential of better and stronger osseointegration, specifi cally through incorporating lattice structure design.

Allgemeine Aspekte beim Einsatz textiler Strukturen für die Implantation

Due to their fibrous structures and various textile construction possibilities, textile structures demonstrate a lot of versatile characteristics. They perform different functions and tasks like for example tissue replacement and tissue augmentation or serve as carrier or scaffold for cells. Textile fabrics like woven fabrics, warp and weft knits or nonwovens have different properties depending on the textile construction (kind of binding, main fiber orientation), which may be used to accomplish an indication-specific function. Biocompatibility and in vivo behavior of a medical device are also influenced by the structure of the product: in the case of textile structures the most important parameters are the kind of construction, wall thickness, yarn size, porosity, and pore size as well as surface roughness. Novel or improved polymeric materials are developed, which in combination with polymeric membrane systems will enable a new generation of implants in the form of biohybrid organs. The combination with stents used as micro-invasive OP systems will reduce operative procedure and the operation risks.