Fig 1 - uploaded by Guy Sovak
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Radiograph showing the position of the implant within the femur. It traverses the head of femur into the medullary canal.
Source publication
Coating titanium alloy implants with titanium nitride (TiN) by the method of Powder Immersion Reaction Assisted Coating (PIRAC) produces a stable layer on their surface. We have examined the ability of the new TiN coating to undergo osseointegration. We implanted TiN-coated and uncoated Ti6Al4V alloy pins into the femora of six-month-old female Wis...
Contexts in source publication
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... neally. An incision 2 cm long was made on the medial side of the knee and, after pushing the patella aside, a hole was drilled with a 21G injection needle from the intercondylar notch through the spongy bone of the distal epiphysis. TiN- coated and uncoated implants were inserted into the left and right femoral medullary canal, respectively (Fig. 1). The fasciae and skin were sutured separately and no extern- al bandages were applied. Each animal was given a single dose of 10 mg/kg body-weight of gentamicin (Vitamed, Bat Yam, Israel). They recovered quickly from surgery and were allowed full movement and weight-bearing imme- diately ...
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... findings. Figure 1 shows that the implants cross the distal head of femur into the medullary cavity. ...
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... have formed around both TiN-coated ( Fig. 3a) and uncoated (Fig. 3b) implants. Close contact was observed between the bone layer and the surface of the implant. To confirm that the socket is indeed bone, SEM-EPMA was performed at three sites in the vicinity of the implant (Fig. 3a). Typical EPMA spectra are shown in Figure 4. In the bone marrow ( Fig. 3a-1) only two peaks were detected, those of carbon (C) and oxygen (O), the signal of C being much stronger than that of O (Fig. 4a). In the EPMA spectrum of the tissue which appears as mature bone ( Fig. 3a-2), strong calcium (Ca) and phospho- rus (P) signals were detected. Also, the signal of O became much stronger than that of C, as ...
Citations
... It has much less wear compared to the cobalt chromium implants that are typically used for shoulder replacement and other resurfacing implants. In addition to reduced wear, there are no metal ions released into the tissues and, therefore, no chance of metal sensitivity or an allergic reaction [18][19][20]. The glenoid component, when needed, is either cemented or porous-backed polyethylene [10,15] (Figure 2). ...
... A total of 55 resurfacing hemiarthroplasty patients had a different prosthesis on the other side: a stemmed total shoulder replacement (19), stemmed hemiarthroplasty (18), total shoulder resurfacing (9), reverse shoulder arthroplasty (7), and resurfacing hemiarthroplasty for rotator cuff arthropathy (2). A total of 11 shoulder arthroplasty patients had a different prosthesis on the other side: stemmed total shoulder replacement (5), stemmed hemiarthroplasty (3), resurfacing hemiarthroplasty (2), and reverse total shoulder arthroplasty (1). ...
Shoulder resurfacing is a versatile, bone-conserving procedure to treat arthritis, avascular necrosis, and rotator cuff arthropathy. Shoulder resurfacing is of interest to young patients who are concerned about implant survivorship and those in need of a high level of physical activity. Using a ceramic surface reduces wear and metal sensitivity to clinically unimportant levels. Between 1989 and 2018, 586 patients received cementless, ceramic-coated shoulder resurfacing implants for arthritis, avascular necrosis, or rotator cuff arthropathy. They were followed for a mean of 11 years and were assessed using the Simple Shoulder Test (SST) and Patient Acceptable Symptom State (PASS). CT scans were used in 51 hemiarthroplasty patients to assess the glenoid cartilage wear. Seventy-five patients had a stemmed or stemless implant in the contralateral extremity. A total of 94% of patients had excellent or good clinical results and 92% achieved PASS. 6% of patients required a revision. A total of 86% of patients preferred their shoulder resurfacing prosthesis over a stemmed or stemless shoulder replacement. The glenoid cartilage wear at a mean of 10 years was 0.6 mm by a CT scan. There were no instances of implant sensitivity. Only one implant was removed due to a deep infection. Shoulder resurfacing is an exacting procedure. It is clinically successful, with excellent long-term survivorship in young and active patients. The ceramic surface has no metal sensitivity, very low wear, and, therefore, it is successful as a hemiarthroplasty.
... Superior mechanical properties of metals have made it the most suitable option for surgeries. Studies have been conducted on economic feasibility and viability of various metals and alloys for this purpose (Sovak et al. 2000). Stainless steel, cobalt-chrome alloy, commercially pure titanium (cpTi), and titanium alloys are commonly used metal implants (Søballe 1993). ...
Calcium fluoride (CaF 2 ) is widely used for different bio applications ranging from biomedical imaging to cell labeling. The biocompatible properties of CaF 2 combined with superior mechanical properties of titanium alloy makes it a perfect choice for orthopedic and dental implants. A dip-coating process was employed to develop a thin film of CaF 2 coating on Ti6Al4V material with an intermediate thin layer of shellac (natural resin). The developed coating was subjected to X-ray powder diffraction method (XRD) and scanning electron microscopy (SEM) to evaluate the surface characteristics. The dip-coated implant material was also subjected to mechanical property evaluation, dissolution behavior study, and corrosion behavior study. In vitro study of the developed implant material was also carried out to assess the biocompatibility. The obtained results suggest use of CaF 2 coating developed by this method for producing biocompatible orthopedic implants.
... The diffusion of metal ions from the implant material can be reduced by coating their surface with TiN and thick TiO 2, which may be potential in vivo applications [85,86]. In vivo biocompatibility studies are carried for the TiN coated specimens by implanting them into rabbits [87], rats [88,89] and dogs [90]. The TiN coated stainless steel was implanted in dog femurs, and the implants did not show any bone opposition for 4 weeks. ...
... The implants showed good alkaline phosphatase activity by observing the bone layer nearby the implants. Improved ALP activity and weaker activity of tartrate-resistant acid phosphatase were revealed histochemically [88]. The implant studies confirm the non-toxic nature and bone formation on the coatings. ...
... The nontoxic nature of DLC and its biocompatibility was confirmed by growing various cell type's in-vitro onto it and learning the cell's response. Different types of cell lines like fibroblasts, human myeloblastic ML-1, SaOS2, MC3T3-E1 cells, macrophages, embryo kidney 293 cells, hBMSCs, etc. and their responses such as cell adhesion, viability, proliferation, cell morphology, differentiation and cytoskeletal architecture have been examined [88,152,209,[216][217][218][219][220][221]. The viability of cells was measured by an enzyme named Lactate dehydrogenase (LDH), which was released in the death of cells. ...
Thin films have emerged as an ideal surface treatment to the permanent implant materials to enhance properties such as biodegradation resistance, better mechanical strengths and biocompatibility. A perfect implant ought to have the ability of resistance to degradation, stimulate osseointegration, prevent bacterial adhesion, and decrease prosthetic infection. The clinical success of implants depends on the interaction of cells with material surfaces, which is an essential factor. Recent development in biomaterials has brought a variety of coatings on biomaterial to overcome these issues. The coatings impart biocompatibility, better mechanical property, and bioactivity to the biomaterial. In this review, the recent trends in surface modification by thin films of implants have been discussed in detail.
... Traditional technologies of producing titanium implants are time-consuming and expensive. Therefore, rapid prototyping (RP) methods are becoming more and more popular-as a result of their unquestionable advantages and possibilities [8][9][10]. These methods rely on additive manufacturing (AM) of nearly ready to use implants, by creating them layer by layer. ...
... The assessment of the osteoinduction of medical material is the basis for further evaluation of its long-term functionality [4,6,8]. For this reason, the in vitro study of the possibility of hydroxyapatite formation on PEEK GRF30 and Ti6Al4V SLM also allows one to evaluate the functionality of appropriate orthopedic implants, spine implants, craniofacial implants, or implants for direct skeletal attachment of a limb prosthesis. ...
In recent years, scientists have defined two main paths for orthopedic implant fabrication: searching for new materials with properties closest to natural bone in order to reduce the stress-shielding effect or creating individually adapted geometry of the implant with the use and Rapid Prototyping methods. Therefore, materials such as PEEK GRF30 and Ti6Al4V selective laser melting (SLM) are of interest. They are defined as materials suitable for implants, however, the knowledge of their bioactivity, a feature which is one of the most desirable properties of biomaterials, is still insufficient. Using Simulated Body Fluid and Hank’s Balanced Salt Solution, the bioactivity of PEEK GRF30 and Ti6Al4V SLM was assessed, as well as commercial Ti6Al4V as a reference material. Ten cylindrical samples of each material were prepared and immersed in solutions per period from 2 to 28 days at 37 °C. Optical analysis of the changes on the examined surfaces suggested that right after 2-day crystals with different morphologies were formed on each material. Further analysis of the chemical composition of the altered surfaces confirmed the formation of a calcium phosphate layer on them, however, the Ca/P ratio was slightly different from 1.67. On the basis of the obtained results, it can be concluded that both PEEK GRF30 and Ti6Al4V SLM are characterized by appropriate—comparable to Ti6Al4V—bioactivity.
... Here, we built of these data to first ask if the age-related loss in trabecular bone seen in the distal femur was accompanied by reduced endogenous Wnt signaling. Second, we used a modified mouse femoral implant model [16] to determine the extent to which Wnt-responsive cells in the distal femur participated in femoral implant osseointegration. Last, we directly tested if delivery of WNT protein therapeutic to the peri-implant environment could accelerate the rate of peri-implant bone formation around a femoral implant. ...
Wnt signaling maintains homeostasis in the bone marrow cavity: if Wnt signaling is inhibited then bone volume and density would decline. In this study, we identified a population of Wnt-responsive cells as osteoprogenitor in the intact trabecular bone region, which were responsible for bone development and turnover. If an implant was placed into the long bone, this Wnt-responsive population and their progeny contributed to osseointegration. We employed Axin2CreCreERT2/+;R26mTmG/+ transgenic mouse strain in which Axin2-positive, Wnt-responsive cells, and their progeny are permanently labeled by GFP upon exposure to tamoxifen. Each mouse received femoral implants placed into a site prepared solely by drilling, and a single-dose liposomal WNT3A protein was used in the treatment group. A lineage tracing strategy design allowed us to identify cells actively expressing Axin2 in response to Wnt signaling pathway. These tools demonstrated that Wnt-responsive cells and their progeny comprise a quiescent population residing in the trabecular region. In response to an implant placed, this population becomes mitotically active: cells migrated into the peri-implant region, up-regulated the expression of osteogenic proteins. Ultimately, those cells gave rise to osteoblasts that produced significantly more new bone in the peri-implant region. Wnt-responsive cells directly contributed to implant osseointegration. Using a liposomal WNT3A protein therapeutic, we showed that a single application at the time of implant placed was sufficient to accelerate osseointegration. The Wnt-responsive cell population in trabecular bone, activated by injury, ultimately contributes to implant osseointegration. Liposomal WNT3A protein therapeutic accelerates implant osseointegration in the long bone.
... Therefore, in recent years there has been active scientific research on the use of titanium alloys with superthin ceramic coatings in resurfacing endoprosthetics. Moreover, titanium is usually used as a metal and titanium nitride (TiN) as a coating [2,3]. The structure of the surface layer of the coating plays a key role in the wear process and is determined by the methods and regimes of its application. ...
The chapter presents recent advances in developing numerical models for multiscale simulation of the femur–endoprosthesis system for the case of hip resurfacing arthroplasty. The models are based on the movable cellular automaton method, which is a representative of the discrete element approach in solid mechanics and allows correctly simulating mechanical behavior of a variety of elastoplastic materials including fracture and mass mixing. At the lowest scale, the model describes sliding friction between two rough surfaces of TiN coatings, which correspond to different parts of the friction pair of hip resurfacing endoprosthesis. At this scale, such parameters of the contacting surfaces as the thickness, roughness, and mechanical properties are considered explicitly. The next scale of the model corresponds to a resurfacing cap for the femur head rotating in the artificial acetabulum insert. Here, sliding friction is explicitly computed based on the effective coefficient of friction obtained at the previous scale. At the macroscale, the proximal part of the femur with a resurfacing cap is simulated at different loads. The bone is considered as a composite consisting of outer cortical and inner cancellous tissues, which are simulated within two approaches: the first implies their linear elastic behavior, the second considers these tissues as Boit’s poroelastic bodies. The later allows revealing the role of the interstitial biological fluid in the mechanical behavior of the bone. Based on the analysis of the obtained results, the plan for future works is proposed.
... Therefore, it exhibits poor adhesion and hence, poor tribological resistance [10,11]. Thus, it is not at all surprizing to note that various surface coatings in the corresponding articulating regions fail often in cyclic loading [12][13][14][15]. ...
... If the FH becomes more fatigue resistant, its fatigue life will be obviously enhanced. As a result, the commonly noted [12][13][14][15] failure of Ti6Al4V FH utilized in HI should be definitely avoidable. It is therefore evident that especially in aged population, the reduction of failure in FHs used in THR could minimize or even eliminate the need for revision surgery. ...
... However, as discussed above; the pertinent knowledge base [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] is far from comprehensive as well as complete. In fact globally, there is no study reported yet on the experimental utilization of a combinatorial approach as mentioned above; to address the issue of Ti6Al4V FH failure due to cyclic loading-unloading that happens in THR application. ...
A major problem with femoral head (FH) for hip implant (HI) applications is that it often fails in service. As a result, revision surgery becomes a must. The related trauma is tremendous for the patient, especially the aged ones. This also implies additional expenses. Keeping these aspects of the problem in view, here we report the development of wear, corrosion and fatigue resistant Ti6Al4V alloy based FH; by a duplex surface engineering (DSE) technique. Thus, the DSE based FHs are developed by a novel combination of plasma nitriding (PN) and Ti/TiN multilayer coating (MLC). The MLCs are formed by magnetron sputtering technique. The Ti6Al4V based FHs are called Ti. The only plasma nitrided FHs are called TiPN. The DSE based FHs are called TiPNML. The corrosion resistances are studied in hank's solution. The sliding wear resistance is studied in simulated body fluid (SBF). The biocompatibilities are studied by the standard MTT assay technique. The cyclic fatigue resistance behaviour up to one million walking cycles is studied in SBF in a HIP simulator with the UHMWPE acetabular cups used as the counter bodies in articulation. The results of the corrosion, biocompatibility, wear, and cyclic fatigue resposnses clearly reveal that the performances of the TiPNML and TiPN FHs are much better than that of the Ti based FHs. The reasons behind such spectacular improvement in biocompatibility as well as corrosion, wear and fatigue resistance are explained in terms of the prevalent phases, microstructural factors, wear mechanisms and surface roughness. The implications of the current results in terms of futuristic FH developments for HI applications are discussed. Such futuristic FH development could provide better HI. These prospects would minimize HI failure and hence, revision surgeries. Thus, the related trauma for numerous patients; especially the aged ones; could be significantly reduced.
... Während zu TiN und Ag, sowohl als alleinige Implantatbeschichtungen aber auch in Verbindung mit anderen Substanzen, zahlreiche in vitro als auch in vivo Studien vorliegen (Cheng et al. 2014, Hauschild et al. 2015, van Hove et al. 2015, Liu et al. 2019, wurde das knöcherne Einwachsen von TiAgN -beschichteten Implantaten im Tiermodell bisher nicht analysiert. Für die Osseointegration TiN -beschichteter Titanimplantate zeigt sich in der Fachliteratur kein Unterschied zwischen den beschichteten Implantaten im Vergleich zu den unbeschichteten Kontrollen (Sovak et al. 2000, Scarano et al. 2003, Larsson Wexell et al. 2013, Sovak et al. 2015. Ebenso wird für Implantate mit Ag enthaltenden Beschichtungen ein gutes knöchernes Einwachsverhalten berichtet (Ruan et al. 2011, Yonekura et al. 2011, Akiyama et al. 2013, Cheng et al. 2014, Eto et al. 2015, Hauschild et al. 2015, Liu et al. 2019 Beschichtung erfolgte mittels PVD (Moseke et al. 2011). ...
... Die amorphen AgHA -Beschichtungen wiederum wurden thermisch aufgespritzt (Akiyama et al. 2013, Eto et al. 2015 In einigen klinischen und Tierstudien wird die Anwesenheit von Bindegewebe am Implantat -Knochen -Interface beschrieben, die auf zu frühe Bewegung, Belastung oder Implantat -Instabilität zurückgeführt wird (Rao et al. 1998, Viceconti et al. 2000. In der vorliegenden Tierstudie kann für die Kaninchen Nr. (Sovak et al. 2000, Scarano et al. 2003, Ruan et al. 2011, Yonekura et al. 2011, Akiyama et al. 2013, Larsson Wexell et al. 2013, Cheng et al. 2014, Eto et al. 2015, Hauschild et al. 2015, Sovak et al. 2015 (Rossi et al. 2014, Roze et al. 2014, Mainetti et al. 2015, Mainetti et al. 2016 ...
Infektionen von Endoprothesen sind auch heute noch, obgleich aufgrund aktueller Hygienestandards seltener, eine schwerwiegende Komplikation. Die Folgen können risikoreiche Revisionsoperationen bis hin zum kompletten Prothesenverlust sein. Um die Gefahr bakterieller Protheseninfektionen zu minimieren, rückten unter anderem Oberflächenbeschichtungen mit antimikrobieller Wirkung in den Fokus der Forscher. Eine Kombination aus dem antimikrobiell wirksamen Metall Silber und dem die Härte verbessernden Stickstoff – als TiAgN – Beschichtung – zeigte bereits gute in vitro Ergebnisse (Moseke et al. 2011). Auf Grundlage dieser positiven in vitro Studie wurde die TiAgN – Beschichtung in der hier vorliegenden Arbeit in vivo im Tiermodell untersucht. Ziel der Studie war es das Einwachsen TiAgN – beschichteter Titanimplantate im Kaninchenknochen mit unbeschichteten Titanimplantaten zu vergleichen. Hierzu wurden bei insgesamt drei Kaninchen jeweils zwei TiAgN – beschichtete Proben und eine unbeschichtete Kontrolle in beide Femora implantiert. Der Einheilzeitraum betrug drei Monate. Nach der Entnahme der Femora wurde zunächst durch Röntgenaufnahmen die genaue Lage der Implantate festgesellt. Nach der Anfertigung von Dünnschliffen nach Donath und der Trichrom – Färbung nach Masson – Goldner wurden für die histologische Auswertung lichtmikroskopische Bilder in 40 – facher Vergrößerung angefertigt. Um den gesamten Umfang der Implantatanschnitte vermessen zu können, wurden die aufgenommen Einzelbilder zu den ursprünglichen Gesamtbildern zusammengesetzt. Die Vermessung der Implantatumfänge erfolgte hinsichtlich der Untersuchungsparameter Knochen – Implantat – Kontakt (KIK), nicht mineralisierter Knochen (Osteoid), Bindegewebe und Spalten – Implantatoberflächenbereiche an denen kein Gewebe angewachsen ist. Für die drei beobachteten Kaninchen ergab sich für die TiAgN – beschichteten Probeimplantate ein KIK von 94,87 %, ein Osteoidanteil am KIK von 45,15 % und ein Spaltanteil von 2,82 % verglichen mit den unbeschichteten Kontrollen von 97,31 % für den KIK, 60,12 % für den Osteoid – sowie 2,69 % für den Spaltanteil. Somit zeigt sich für TiAgN – beschichtete Titanimplantate kein signifikant schlechteres Einwachsen im Vergleich zu unbeschichteten Titanimplantaten. Ausgehend von der guten antimikrobiellen Wirksamkeit und Zytokompatibilität in vitro (Moseke et al. 2011) sowie der guten Osseointegration in vivo präsentiert sich diese Beschichtung sehr vielversprechend. Dennoch sind weitere Untersuchungen erforderlich, wie beispielsweise die Überprüfung der Haftfestigkeit zwischen Beschichtung und Implantat sowie die antimikrobielle Wirksamkeit in vivo. Ergeben sich für diese Beschichtung weiterhin gute Ergebnisse, kann eine Studie am Menschen in Erwägung gezogen werden.
... 10,11 Various surface modification techniques have been applied to improve the osseointegration capacity of titanium alloy implants, mainly including surface texturing design 12−15 and surface coating design. 16,17 Usually, surface texturing design was applied to obtain a surface structure, which is important in determining the implant performance, including etching, sand blasting, abrading, and laser treatments. 11,18 However, considering the drawbacks, such as danger and toxicity from etching and abrading, surface damage, and uncontrollability from the sand blasting method, laser texturing treatment is more suitable for surface modification of implants, owing to its environmental friendliness, accuracy, versatility, and rapid adaptability. ...
... The structure of the coating is determined by the regimes of its deposition. Usually, the following technologies are used for this purpose: physical vapor deposition (PVD), chemical vapor deposition (CVD) and powder immersion reaction assisted coating (PIRAC) [2,3]. The coating obtained by PVD and CVD techniques have low adhesion and may delaminate under dynamic loading, while adhesion of the coating obtained by PIRAC is much higher. ...
Friction between the moving parts of the endoprosthesis has a significant impact on the endoprosthesis operation time. Primarily, it concerns the endoprosthesis of hip and knee joints. To improve the tribological characteristics of the metal endoprosthesis, hardening nanostructured coatings are used. Usually, titanium and titanium alloys are used as metal, and titanium nitride is used as a coating. Herein, we propose an approach to multilevel modeling of the system “bone-endoprosthesis” which is based on the movable cellular automaton method and accounts for friction between the moving parts of the hip resurfacing endoprosthesis. We validated the models of the friction system materials using the instrumented scratch test simulation. Then, we simulated friction at the mesolevel, explicitly considering roughness of the coating. The results obtained at the mesolevel were used as tribological characteristics of the coating in the macroscopic model of the hip resurfacing endoprosthesis.
