Journal articles on the topic 'Orthopedic implants – Strength of materials'
To see the other types of publications on this topic, follow the link: Orthopedic implants – Strength of materials.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Orthopedic implants – Strength of materials.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Zaman, Hainol Akbar, Safian Sharif, Mohd Hasbullah Idris, and Anisah Kamarudin. "Metallic Biomaterials for Medical Implant Applications: A Review." Applied Mechanics and Materials 735 (February 2015): 19–25. http://dx.doi.org/10.4028/www.scientific.net/amm.735.19.
Full textAbstract:
Stainless steel, titanium alloys and cobalt chromium molybdenum alloys are classified under the metallic biomaterials whereby various surgical implants, prosthesis and medical devices are manufactured to replace missing body parts which may be lost through accident, trauma, disease, or congenital conditions. Among these materials, cobalt chromium molybdenum alloys are the common cobalt base alloy used for orthopedic implants due their excellence properties which include high corrosion resistance, high strength, high hardness, high creep resistance, biocompatibility and greater wear resistance. This paper summarises the various aspects and characteristic of metallic biomaterials such as stainless steel, titanium and cobalt chromium alloys for medical applications especially for orthopedic implant. These include material properties, biocompatibility, advantages and limitations for medical implants applications.
2
Mori, Yu, Naoya Masahashi, and Toshimi Aizawa. "A Review of Anodized TiNbSn Alloys for Improvement in Layer Quality and Application to Orthopedic Implants." Materials 15, no. 15 (July 22, 2022): 5116. http://dx.doi.org/10.3390/ma15155116.
Full textAbstract:
Titanium alloys are useful for application in orthopedic implants. However, complications, such as prosthetic infections and aseptic loosening, often occur after orthopedic devices are implanted. Therefore, innovation in surface modification techniques is essential to develop orthopedic materials with optimal properties at the biomaterial–bone interface. In this review, we present recent research on the improvement in the osteoconductivity and antibacterial effect of the Ti-33.6% Nb-4% Sn (TiNbSn) alloy by anodic oxidation and other related studies. TiNbSn alloys are excellent new titanium alloys with a low Young’s modulus, high tensile strength, and with gradient functional properties such as a thermally adjustable Young’s modulus and strength. Titanium dioxide (TiO2), when obtained by the anodic oxidation of a TiNbSn alloy, improves bone affinity and provides antibacterial performance owing to its photocatalytic activity. The safety of TiO2 and its strong bonding with metal materials make its method of preparation a promising alternative to conventional methods for improving the surface quality of orthopedic implants. Implementing anodization technology for TiNbSn alloys may alleviate orthopedic surgery-related complications, such as loosening, stress shielding, and infection after arthroplasty.
3
Parcharoen, Yardnapar, Preecha Termsuksawad, and Sirinrath Sirivisoot. "Improved Bonding Strength of Hydroxyapatite on Titanium Dioxide Nanotube Arrays following Alkaline Pretreatment for Orthopedic Implants." Journal of Nanomaterials 2016 (2016): 1–13. http://dx.doi.org/10.1155/2016/9143969.
Full textAbstract:
Hydroxyapatite (HA) is a bioactive bone substitute used in biomedical applications. One approach to use HA for bone implant application is to coat it on titanium (Ti) implant. However, adhesion of HA on Ti is major concern for their long-term use in orthopedic implants. To enhance the adhesion strength of HA coating on titanium (Ti), the surface of the Ti was anodized and alkaline pretreated prior to coating on Ti by electrodeposition. Alkaline pretreatment of titanium dioxide nanotubes (ATi) accelerated the formation of HA, which mimicked the features and structure of natural bone tissue. Nanostructured HA formed on the ATi and pretreated ATi (P-ATi), unlike on conventional Ti. This study is the first to show that the bonding of HA coating to a P-ATi substrate was stronger than those of HA coating to Ti and to ATi. The preosteoblast response tests were also conducted. The results indicated that HA coating improved preosteoblast proliferation after 3 days in standard cell culture.
4
Pelekhan, Bohdan, Maciej Dutkiewicz, Ivan Shatskyi, Andrii Velychkovych, Mykola Rozhko, and Liubomyr Pelekhan. "Analytical Modeling of the Interaction of a Four Implant-Supported Overdenture with Bone Tissue." Materials 15, no. 7 (March 24, 2022): 2398. http://dx.doi.org/10.3390/ma15072398.
Full textAbstract:
Today, an interdisciplinary approach to solving the problems of implantology is key to the effective use of intraosseous dental implantations. The functional properties of restoration structures for the dentition depend significantly on the mechanical stresses that occur in the structural elements and bone tissues in response to mastication loads. An orthopedic design with a bar fixation system connected to implants may be considered to restore an edentulous mandible using an overdenture. In this study, the problem of the mechanics of a complete overdenture based on a bar and four implants was formulated. A mathematical model of the interaction between the orthopedic structure and jawbone was developed, and a methodology was established for the analytical study of the stress state of the implants and adjacent bone tissue under the action of a chewing load. The novelty of the proposed model is that it operates with the minimum possible set of input data and provides adequate estimates of the most significant output parameters that are necessary for practical application. The obtained analytical results are illustrated by two examples of calculating the equivalent stresses in implants and the peri-implant tissue for real overdenture designs. To carry out the final assessment of the strength of the implants and bone, the prosthesis was loaded with mastication loads of different localization. In particular, the possibilities of loading the prosthesis in the area of the sixth and seventh teeth were investigated. Recommendations on the configuration of the distal cantilever of the overdenture and the acceptable level and distribution of the mastication load are presented. It was determined that, from a mechanical point of view, the considered orthopedic systems are capable of providing long-term success if they are used in accordance with established restrictions and recommendations.
5
Morozova, Oksana, and Edwin Gevorkyan. "CURRENT STATE OF APPLIENCE ZIRCONIUM DIOXIDE IN BIOENGINEERING." Technology transfer: fundamental principles and innovative technical solutions 4 (November 30, 2020): 39–42. http://dx.doi.org/10.21303/2585-6847.2020.001509.
Full textAbstract:
This descriptive review presents current knowledge about the bioengineering use of a zirconium dioxide, the advantages and disadvantages of the material, and the prospects for research in this direction. The work reflects the success of the practical application of the zirconium dioxide as a material for dental structures and biological implants. Such practical characteristics, such as color-stability, chemical stability, good aesthetics, biocompatibility and durability, allowed to actively use the zirconium dioxide as a material for producing various dental structures. In comparison with other ceramics, the presence of high-performance of strength and fracture toughness of the zirconium dioxide enables the use of this material as an alternative material for the reconstructions in the readings with considerable loads. High hardness determines the zirconium dioxide as an excellent material for articular prostheses, because of its hardness, provides a low level of wear and excellent biocompatibility. However, along with positive characteristics, a widespread practical problem of using the zirconium dioxide in dentistry is a chip or fracture of veneering ceramics. It has also been reported that there is a shortage of orthopedic implants such as hydrothermal stability. The solution of such problems is indicated and the use of composite materials based on the zirconium dioxide, which allows to solve a similar problem, as well as to increase the service life and reliability of orthopedic implants by providing a higher fracture toughness and mechanical strength. The existence of such composite materials based on the zirconium dioxide provides a significant increase in the wear resistance of orthopedic implants, which is essential for successful prosthetics
6
Grądzka-Dahlke, Małgorzata. "Comparison of Functional Properties of Thin Layers on Titanium and Cobalt Implant Alloys." Defect and Diffusion Forum 297-301 (April 2010): 1053–58. http://dx.doi.org/10.4028/www.scientific.net/ddf.297-301.1053.
Full textAbstract:
The development of arthroplastics places high demands on the materials used for load-bearing elements of orthopedic implants. The most common of implant materials are titanium and cobalt alloys due to their excellent mechanical properties and biocompatibility. Titanium alloys have desirable properties, such as relatively low modulus, good fatigue strength, formability, machinability, superior corrosion resistance and so are frequently used for long-term implants. However, poor wear resistance limits their application for tribological systems of artificial joints. Research on improvement of titanium alloys tribological properties have been undertaken, mainly by using thin coatings. The TiN-layers are reported to be most promising in biomedical applications such. Many authors stress that application of TiN layer improve wear resistance of titanium implant alloys. Presented work is focused on comparison of effect of TiN coating on properties of TiAlV and CoCrMo implant alloys. The structure, microhardness, corrosion resistance as well as tribological properties were analysed. The research did not confirmed the good properties of titanium alloy with TiN coating. The results show that matrix metal hardness definitely affects the efficiency of TiN layers.
7
Petrovici, Ilaria Lorena, Mihai Catalin Tenovici, Razvan Cristian Vaduva, Danut Nicolae Tarnita, Dragoş Laurenţiu Popa, Georgiana Vintila, Otilia Rogoveanu, and Bogdan Capitanescu. "Virtual Implantology System Used for Long Bones Simulation Studies." Advanced Engineering Forum 34 (October 2019): 151–58. http://dx.doi.org/10.4028/www.scientific.net/aef.34.151.
Full textAbstract:
The basic concepts of Kuntscher's centromedular osteosynthesis remain largely valid today: centromedular osteosynthesis must be conducted under fluoroscopic control and without fracture outbreak exposure to avoid contamination, the rod must be strong enough to withstand stress caused by muscle contraction, joint movement and body weight load, this to avoid twisting and tearing the rod, the rod must exhibit sufficient elasticity to compress during insertion into the canal and then re-expand for firmly fix the fracture fragments and prevent their rotation. On the other hand, osteosynthesis with flexible centromedullary rods is mainly used in pediatric surgery where elastic rods in secant arch are used applying the principles of stable elastic osteosynthesis. Starting from the research done worldwide, we examined the orthopedic implants used in the long bones as a whole and some inconsistencies were found between the osteosynthesis material and the bone tissue. The necessary materials used in the study are orthopedic implants, different in structure, elasticity, dimensions, which were tested on bone virtual models, according to the CT scan sections. With the help of normal bone virtual models, both bone strength, various orthopedic implants, and the resistance of the osteosynthesis material used were taken into account. On these complete virtual models various simulations were made using FEM. The potential for FEM use in orthopedics and biomechanics has often been overestimated. In many situations, inappropriate use of the method on complicated biological structures can become costly, inefficient or prone to errors. Also, nonlinear soft tissue material has created new difficulties. But these disadvantages and limitations have been diminished successively through new results of biomechanical researches, but also by improving the method by using new types of finite elements. From this results database obtained through various virtual experiments, account will be taken of the most common accidents and incidents occurring in the implanted bone, and solutions will be sought to improve post-implant bone quality.
8
Cirstoiu, Catalin, Razvan Ene, Dan Popescu, and Monica Cirstoiu. "Osteosynthesis Material Failure: Poor Fixation or Material Defect." Advanced Materials Research 717 (July 2013): 249–52. http://dx.doi.org/10.4028/www.scientific.net/amr.717.249.
Full textAbstract:
Rising rate of high energy trauma, mainly due to increasing life expectancy of the population on a global scale in recent decades and more intense daily activity, involves the need to address the increase of more complex fractures, thus putting to the test the experience of trauma surgeon and the quality of various osteosynthesis materials. Metallic materials designed for orthopedic implants must present a group of properties that strength, biocompatibility and resistance to degradation (corrosion or wear) are of primary importance. To reach these objectives, the materials used in the manufacture of orthopedic implants must meet standard requirements. These requirements include primarily standard chemical composition, microstructure and macroscopic appearance. In this paper we present a study to determine the cause of degradation of osteosynthesis material. The most frequent causes of degradation include poor or unstable fixation of osteosynthesis or material defects. A valuation technique, including optical and scanning electron microscopy (SEM) was used to assess aspects of macroscopic and microstructural degradation and chemical composition of implants. These assessments showed that both design errors and inappropriate surgical procedures were due to failures.
9
Tappa, Karthik, Udayabhanu Jammalamadaka, Jeffery Weisman, David Ballard, Dallas Wolford, Cecilia Pascual-Garrido, Larry Wolford, Pamela Woodard, and David Mills. "3D Printing Custom Bioactive and Absorbable Surgical Screws, Pins, and Bone Plates for Localized Drug Delivery." Journal of Functional Biomaterials 10, no. 2 (April 1, 2019): 17. http://dx.doi.org/10.3390/jfb10020017.
Full textAbstract:
Additive manufacturing has great potential for personalized medicine in osseous fixation surgery, including maxillofacial and orthopedic applications. The purpose of this study was to demonstrate 3D printing methods for the fabrication of patient-specific fixation implants that allow for localized drug delivery. 3D printing was used to fabricate gentamicin (GS) and methotrexate (MTX)-loaded fixation devices, including screws, pins, and bone plates. Scaffolds with different infill ratios of polylactic acid (PLA), both without drugs and impregnated with GS and MTX, were printed into cylindrical and rectangular-shaped constructs for compressive and flexural strength mechanical testing, respectively. Bland PLA constructs showed significantly higher flexural strength when printed in a Y axis at 100% infill compared to other axes and infill ratios; however, there was no significant difference in flexural strength between other axes and infill ratios. GS and MTX-impregnated constructs had significantly lower flexural and compressive strength as compared to the bland PLA constructs. GS-impregnated implants demonstrated bacterial inhibition in plate cultures. Similarly, MTX-impregnated implants demonstrated a cytotoxic effect in osteosarcoma assays. This proof of concept work shows the potential of developing 3D printed screws and plating materials with the requisite mechanical properties and orientations. Drug-impregnated implants were technically successful and had an anti-bacterial and chemotherapeutic effect, but drug addition significantly decreased the flexural and compressive strengths of the custom implants.
10
Mehta, Sahil, Gurmohan Singh, Harvinder Singh, and Abhineet Saini. "A Review of Tribological Behavior of Different Bio-Implant Materials." ECS Transactions 107, no. 1 (April 24, 2022): 5147–53. http://dx.doi.org/10.1149/10701.5147ecst.
Full textAbstract:
Biomedical implants are extensively gaining popularity owing to ever increasing health complications and growth in trauma numbers globally. Metallic implants are the most widely used bio-implants for various orthopedics and dentistry related problems owing to their superior mechanical strength when compared to ceramics and polymers. Furthermore, titanium alloys are the preferred choice these days, because of their proximate nature to human bone and light weight. However, few shortcomings make these artificial bio-implants capricious like short life span, wear rate, surface finish, etc. Tribological behavior and performance affect the life of the implant, and has to be improved for longer sustainability of the implants. Wear tests can help in predicting the life of the movable sliding joints in bio-implants. This paper includes a review about the properties of the bio material, wear tests results, and their wear mechanisms. Further, the limitation and scope of biomaterial implants from tribological aspects of various bio-materials are reviewed.
11
Ivanov, Eugene, Eduardo del Rio, Igor Kapchemnko, Maija Nyström, and Juha Kotila. "Development of Bio-Compatible Beta Ti Alloy Powders for Additive Manufacturing for Application in Patient-Specific Orthopedic Implants." Key Engineering Materials 770 (May 2018): 9–17. http://dx.doi.org/10.4028/www.scientific.net/kem.770.9.
Full textAbstract:
The use and application of alloys as biomedical alloys have increased over the past few years owing to their excellent biocompatibility, corrosion resistance, high mechanical and fatigue resistance, low density, adequate wear resistance, and low elastic modulus. Orthopedic implant materials are exposed to high mechanical loading. Conventional materials based on Ti-6Al-4V, stainless steel or cobalt-chromium alloys demonstrate good mechanical strength, but also some toxicological concerns due to release of toxic elements which may result in inflammatory reactions. Metal alloys based on titanium, zirconium, tantalum and niobium represent higher biocompatibility with appropriate mechanical properties for avoiding stress-shielding and consecutive implant loosening. Application of specifically designed spherical β-titanium alloy powders in additive manufacturing, such as selective laser melting (SLM) or electron beam melting (EBM); enable the production of components with a high degree in freedom of design. Accordingly, SLM or EBM of Ti/Nb (/Ta) alloys offer the possibility to fabricate patient-specific orthopedic implants. The present paper describes development of β-titanium alloys powders designed for application in additive manufacturing technologies. TiNbZrTa (TNZT)-based 3D structures were successfully manufactured and mechanically tested.
12
Ahmed, Furqan, Muhammad Zain-ul-abdein, Iftikhar Ahmed Channa, Muhammad Kamran Yaseen, Sadaf Jamal Gilani, Muhammad Atif Makhdoom, Muhammad Mansoor, Usman Shahzad, and May Nasser bin Jumah. "Effect of Ultrasonic Surface Mechanical Attrition Treatment-Induced Nanograins on the Mechanical Properties and Biocompatibility of Pure Titanium." Materials 15, no. 15 (July 22, 2022): 5097. http://dx.doi.org/10.3390/ma15155097.
Full textAbstract:
Commercially pure titanium (Ti) is widely used in bio-implants due to its high corrosion resistance. However, Ti exhibits marginally low mechanical and tribological properties, which limit its applications in some orthopedic implants. In this work, the Ti samples were subjected to ultrasonic surface mechanical attrition treatment (SMAT) for various durations to improve their surface properties such as hardness, strength and surface energy. SMAT-induced grain refinement was analyzed using optical, scanning electron and atomic force microscopy techniques. A Vickers hardness test was performed to determine the through-thickness hardness. Mechanical testing was carried out to measure the yield strength, ultimate tensile strength and ductility of the specimens. Corrosion tests were performed on a Gamry Potentiostat. The surface energy of SMAT-modified samples was calculated using the Owens–Wendt method. It was observed that SMAT reduced the average grain size from 50 μm to as low as 100 nm. The grain refinement and the corresponding grain boundary density led to a significant improvement in mechanical properties and biocompatibility in terms of increased hardness, yield and tensile strengths, surface energy, corrosion rate and hydrophilicity.
13
Zhu, Bin, Yuqin Zhang, Yongcheng Chen, Ping Yuan, Wentong Wang, Hao Duan, and Zhihua Wang. "Synthesis, Characterization and Antimicrobial Studies of Ti-40Nb-10Ag Implant Biomaterials." Metals 12, no. 8 (August 22, 2022): 1391. http://dx.doi.org/10.3390/met12081391.
Full textAbstract:
Bacterial infection and stress shielding are important issues in orthopedic implants. In this study, Ag element was selected as an antibacterial agent to develop an antibacterial Ti-40Nb-10Ag alloy by spark plasma sintering (SPS). The microstructure, phase constitution, mechanical properties, microhardness, and antibacterial properties of the Ti-40Nb-10Ag sintered alloys with different sintering temperatures were systematically studied by X-ray diffraction (XRD), scanning electron microscope (SEM), microhardness tests, compressive tests, and antibacterial tests. The Ti-40Nb-10Ag alloys were mainly composed of α-Ti, β-Ti, and Ti2Ag intermetallic phases. This study shows that the change in sintering temperature affects the microstructure of the alloy, which results in changes in its microhardness, compressive strength, elastic modulus, and antibacterial properties. At the sintering temperature of 975 °C, good metallurgical bonding was developed on the surface of the alloy, which led to excellent microhardness, compressive strength, elastic modulus, and antibacterial ability with an antibacterial rate of 95.6%. In conclusion, the Ti-40Nb-10Ag alloy prepared by SPS at 975 °C is ideal and effective for orthopedic implant.
14
Le, Bang Thi, Long Bui Duc, Nhung Hong Thi Nguyen, and Eddy. "Calcium Carbonate Coating on Ti by Transformation of CaO Coating Produced by Sandblasting." Key Engineering Materials 932 (September 20, 2022): 157–62. http://dx.doi.org/10.4028/p-s6v5ji.
Full textAbstract:
Titanium was the most commonly used metal in orthopedic implant. However, no direct chemical bond would be possible between the implant and surrounding bone tissue, and so the titanium implants lack the potential to induce rapid bone formation. Coating the titanium with a bioresorbable and osteoconductive layer would have a significant osseointegration. The purpose of this study was to fabricate and characterize calcium carbonate coating. The coating was fabricated on Ti substrate by converting of CaO coating in humidity environment under CO2 flow. The CaO coating was deposited by sandblasting process. The CaCO3 coating was approx. 1.85 µm thick and covered the surface’s surface uniformly. The coating strength was approx. 16.1 MPa and the Ca content in the coating was 2.02 mg/mm2.
15
Abate, Kalayu Mekonen, Aamer Nazir, Jia-En Chen, and Jeng-Ywan Jeng. "Design, Optimization, and Evaluation of Additively Manufactured Vintiles Cellular Structure for Acetabular Cup Implant." Processes 8, no. 1 (December 24, 2019): 25. http://dx.doi.org/10.3390/pr8010025.
Full textAbstract:
Cellular materials with very highly regulated micro-architectures are promising applicant materials for orthopedic medical uses while requiring implants or substituting for bone due to their ability to promote increased cell proliferation and osseointegration. This study focuses on the design of an acetabular cup (AC) cellular implant which was built using a vintiles cellular structure with an internal porosity of 56–87.9% and internal pore dimensions in the range of 600–1200 μm. The AC implant was then optimized for improving mechanical performance to reduce stress shielding by adjusting the porosity to produce stiffness (elastic modulus) to match with the bone, and allowing for bone cell ingrowth. The optimized and non-optimized AC cellular implant was fabricated using the SLM additive manufacturing process. Simulation (finite element analysis, FEA) was carried out and all cellular implants are finally tested under static loading conditions. The result showed that on the finite element model of an optimized implant, cellular has shown 69% higher stiffness than non-optimized. It has been confirmed by experimental work shown that the optimized cellular implant has a 71% higher ultimate compressive strength than the non-optimized counterpart. Finally, we developed an AC implant with mechanical performance adequately close to that of human bone.
16
AL-Maatoq, Marwah, Patricio Fuentealba, Melanie Fachet, Rainer Glüge, Salah H. R. Ali, and Christoph Hoeschen. "Carbon Nanotube-Based Reinforced Polymers for Medical Applications: Improving Impact Strength of Polymer-Polymer Composites." Journal of Nanomaterials 2022 (April 1, 2022): 1–15. http://dx.doi.org/10.1155/2022/1760198.
Full textAbstract:
There is a continuous need for innovative biomaterials with advanced properties to meet the biomechanical requirements of orthopedic implants and interventional devices. Recent research findings show that using material composites leads to significantly improved properties, which are beneficial for medical applications. Therefore, this work aims at studying polymer-polymer composites of high-density polyethylene (HDPE) and ultrahigh molecular weight polyethylene (UHMWPE), which were mixed with and without reinforcement of multiwall carbon nanotubes (MWCNTs) in two steps. An extensive characterization workflow including mechanical tensile tests, tribological performance, and surface characteristics was used to analyze the reinforced polymer-polymer composite samples. The results of the mechanical tests showed that the developed MWCNT-reinforced samples achieved better performance, due to a higher yield point that is the highest in the sample with 48.5% HDPE-50% UHMWPE-0.5% MWCNTs, a higher value in the hardness test peaking in the sample with 49.5% HDPE-50% UHMWPE-0.5% MWCNTs, and a lower friction coefficient in HDPE-UHMWPE-MWCNTs samples. Overall, the reinforcement of polymer-polymer composites with MWCNTs led to a significant improvement of the material characteristics required for the designated use in orthopedic implants and interventional biopsy needles, which will lead to improved clinical results.
17
Hagelstein, Salome, Sergej Zankovic, Adalbert Kovacs, Roland Barkhoff, and Michael Seidenstuecker. "Mechanical Analysis and Corrosion Analysis of Zinc Alloys for Bioabsorbable Implants for Osteosynthesis." Materials 15, no. 2 (January 6, 2022): 421. http://dx.doi.org/10.3390/ma15020421.
Full textAbstract:
Zinc alloys have recently been researched intensely for their great properties as bioabsorbable implants for osteosynthesis. Pure zinc (Zn) itself has relatively poor strength, which makes it insufficient for most clinical use. Research has already proven that the mechanical strength of zinc can be enhanced significantly by alloying it with silver. This study evaluated zinc silver alloys (ZnAg) as well as novel zinc silver titanium alloys (ZnAgTi) regarding their mechanical properties for the use as bioabsorbable implants. Compared to pure zinc the mechanical strength was enhanced significantly for all tested zinc alloys. The elastic properties were only enhanced significantly for the zinc silver alloys ZnAg6 and ZnAg9. Regarding target values for orthopedic implants proposed in literature, the best mechanical properties were measured for the ZnAg3Ti1 alloy with an ultimate tensile strength of 262 MPa and an elongation at fracture of 16%. Besides the mechanical properties, the corrosion rates are important for bioabsorbable implants. This study tested the corrosion rates of zinc alloys in PBS solution (phosphate buffered solution) with electrochemical corrosion measurement. Zinc and its alloys showed favorable corrosion rates, especially in comparison to magnesium, which has a much lower degradation rate and no buildup of hydrogen gas pockets during the process. Altogether, this makes zinc alloys highly favorable for use as material for bioabsorbable implants for osteosynthesis.
18
Shao, Longfei, Yiheng Du, Kun Dai, Hong Wu, Qingge Wang, Jia Liu, Yujin Tang, and Liqiang Wang. "β-Ti Alloys for Orthopedic and Dental Applications: A Review of Progress on Improvement of Properties through Surface Modification." Coatings 11, no. 12 (November 25, 2021): 1446. http://dx.doi.org/10.3390/coatings11121446.
Full textAbstract:
Ti and Ti alloys have charming comprehensive properties (high specific strength, strong corrosion resistance, and excellent biocompatibility) that make them the ideal choice in orthopedic and dental applications, especially in the particular fabrication of orthopedic and dental implants. However, these alloys present some shortcomings, specifically elastic modulus, wear, corrosion, and biological performance. Beta-titanium (β-Ti) alloys have been studied as low elastic modulus and low toxic or non-toxic elements. The present work summarizes the improvements of the properties systematically (elastic modulus, hardness, wear resistance, corrosion resistance, antibacterial property, and bone regeneration) for β-Ti alloys via surface modification to address these shortcomings. Additionally, the shortcomings and prospects of the present research are put forward. β-Ti alloys have potential regarding implants in biomedical fields.
19
Okazaki, Yoshimitsu, Emiko Gotoh, and Jun Mori. "Strength–Durability Correlation of Osteosynthesis Devices Made by 3D Layer Manufacturing." Materials 12, no. 3 (January 31, 2019): 436. http://dx.doi.org/10.3390/ma12030436.
Full textAbstract:
To develop orthopedic implants that are optimized for each patient’s needs or skeletal structure (custom-made implants), evaluations of the bending strength, bending stiffness, and durability of various types of conventional osteosynthesis devices have become important. Four-point bending tests and compression bending tests of osteosynthesis devices (bone plates, intramedullary nail rods, spinal rods, compression hip screws (CHSs), short femoral nails, and metaphyseal plates) were carried out to measure their bending stiffness, bending strength, and durability. The bending stiffness of bone plates, intramedullary nails, spinal rods, CHSs, short femoral nails, and metaphyseal plates increased with increasing bending strength. The durability limit of various types of osteosynthesis devices linearly increased with increasing bending strength. The relationship (durability limit at 106 cycles) = 0.67 × (bending strength) (N·m) (R2 = 0.85) was obtained by regression. The relationship for the highly biocompatible Ti-15Zr-4Nb-4Ta alloy was also linear. The mechanical strength and ductility of specimens that were cut from various osteosynthesis devices were excellent and their microstructures consisted of fine structures, which were considered to be related to the excellent durability. These results are expected to be useful for the development of implants suitable for the skeletal structure of patients using three-dimensional (3D) layer manufacturing technologies.
20
Munteanu, Corneliu, Ștefan Lupescu, Bogdan Istrate, Vasile Iulian Antoniac, Marcelin Benchea, and Adriana Savin. "Some Tribological Aspects of Mg-0.5Ca-xY Biodegradable Materials." Key Engineering Materials 782 (October 2018): 136–41. http://dx.doi.org/10.4028/www.scientific.net/kem.782.136.
Full textAbstract:
Biodegradable materials are a further development of new medical applications, such as orthopedic implants and vascular stents, or the tissue scaffold. The variety of alloying elements introduced into magnesium alloys lead to superior corrosion resistance and mechanical properties similar to the biological bone. From a mechanical point of view, increasing the percentage of calcium leads to decreased strength and elongation resistance, and Yttrium addition greatly improves tensile strength and favors a slower degradation process. Three different Mg-0.5Ca-xY alloys were obtained, varying the concentration of the Y-element. The Mg-0.5Ca-xY system was tested from the point of view of micro-scratch and micro-indentation with three determinations each, obtaining results for Young's mode, micro-hardness, COF and stiffness. These alloys possess mechanical properties for use as orthopaedic applications. As future studies, mechanical properties can be improved by performing heat treatments.
21
Prakash, P. Shakti, S. J. Pawar, and R. P. Tewari. "Synthesis, characterization, and coating of forsterite (Mg2SiO4) based material over medical implants: A review." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 233, no. 6 (April 18, 2017): 1227–40. http://dx.doi.org/10.1177/1464420717705151.
Full textAbstract:
Biocompatible metallic alloys (stainless steel, Ti-alloy, Co–Cr alloys, etc.) have been frequently used for various biomedical implants. Being biocompatible, complications like implant corrosion, body inflammation, organ pain, local infection, and cytotoxicity cannot be avoided. Hydroxyapatite, a common biomaterial, is used in the form of powders, coatings, and composites for biomedical applications. But poor adhesion, poor load-bearing capacity, high dissolution, poor wear resistance, natural fragility, etc. are the few hindrances in the use of hydroxyapatite coating over implants. Hence, there is a need to focus on the development of alternative biomaterials and their coatings for metallic (orthopedic, dental, metallic stents, pacemakers, etc.) implants. To avoid various complexities and to improve the biocompatibility of metal implants, the coating of forsterite and its composites are being used nowadays. Techniques like dip coating, plasma spraying, and electrophoretic deposition are employed for such coatings. In this paper, a review based on methods of preparation of forsterite has been done. For the preparation of forsterite powder, various studies have reported the sintering temperature range to be 800–1450 ℃ and the crystallite size from 10 nm to 100 µm. The forsterite and its composites coating over Ti-alloy and stainless steel have also been reported. This paper also compares the mechanical and biological properties of forsterite and hydroxyapatite. It has been observed that the mechanical properties (hardness, fracture toughness, Young’s modulus, and compressive strength), and biological properties (biocompatibility and bioactivity) of forsterite are favorable for the biomedical implant coating.
22
Bazhenov, Viacheslav, Anastasia Lyskovich, Anna Li, Vasily Bautin, Alexander Komissarov, Andrey Koltygin, Andrey Bazlov, Alexey Tokar, Denis Ten, and Aigul Mukhametshina. "Effect of Heat Treatment on the Mechanical and Corrosion Properties of Mg–Zn–Ga Biodegradable Mg Alloys." Materials 14, no. 24 (December 18, 2021): 7847. http://dx.doi.org/10.3390/ma14247847.
Full textAbstract:
Mg alloys have mechanical properties similar to those of human bones, and have been studied extensively because of their potential use in biodegradable medical implants. In this study, the influence of different heat treatment regimens on the microstructure and mechanical and corrosion properties of biodegradable Mg–Zn–Ga alloys was investigated, because Ga is effective in the treatment of disorders associated with accelerated bone loss. Solid–solution heat treatment (SSHT) enhanced the mechanical properties of these alloys, and a low corrosion rate in Hanks’ solution was achieved because of the decrease in the cathodic-phase content after SSHT. Thus, the Mg–4 wt.% Zn–4 wt.% Ga–0.5 wt.% Y alloy after 18 h of SSHT at 350 °C (ultimate tensile strength: 207 MPa; yield strength: 97 MPa; elongation at fracture: 7.5%; corrosion rate: 0.27 mm/year) was recommended for low-loaded orthopedic implants.
23
Mathai, Suja, and Priyanka S. Shaji. "Different Coating Methods of Titanium Dioxide on Metal Substrates for Orthopedic and Dental Applications: A Review." Asian Journal of Chemistry 34, no. 1 (2021): 9–17. http://dx.doi.org/10.14233/ajchem.2022.23512.
Full textAbstract:
The outstanding physico-chemical characteristics to assist bone regeneration and cell development, titanium dioxide (TiO2) based materials have showed significant promise for applications in implants. Due to its excellent performance in a wide variety of applications, chemical stability, and inexpensive cost, this metal oxide has received the more attention. Coating techniques for creating surfaces made of this substance have been thoroughly investigated. The aim of this review article is to look at the current status of TiO2 technology for orthopedic and dental implants. Over the years, researchers have investigated several TiO2 coating deposition techniques on metal implants, with the goal of improving adhesion strength and long-term dependability. This review examines a variety of TiO2 deposition techniques on metal substrates in depth. Anodization, sol-gel method, plasma spray coating, cold spray coating, high velocity oxy-fuel spray, high velocity suspension flame spraying, pulsed laser deposition (PLD), ion beam deposition (IBD), magnetron sputtering deposition, electrophoretic deposition (EPD), electrochemical deposition and biomimetic deposition are among the methods examined.
24
Das, Ashish, and Mukul Shukla. "Surface morphology, bioactivity, and antibacterial studies of pulsed laser deposited hydroxyapatite coatings on Stainless Steel 254 for orthopedic implant applications." Proceedings of the Institution of Mechanical Engineers, Part L: Journal of Materials: Design and Applications 233, no. 2 (August 10, 2016): 120–27. http://dx.doi.org/10.1177/1464420716663029.
Full textAbstract:
Coating of hydroxyapatite using the pulsed laser deposition technique, on medical grade UNS S31254 stainless steel (254SS), to yield a biomaterial for potential orthopedic implant applications, is unreported so far in the literature. In this paper, the pulsed laser deposition process was used to improve the physiological response of 254SS. The surface morphology of the deposited hydroxyapatite coatings was characterized using scanning electron microscopy and atomic force microscopy, while the phase composition of the deposited hydroxyapatite coatings was determined using the X-ray diffraction method. The thickness and adhesive strength of the hydroxyapatite coatings were determined using an ellipsometer and a tensometer, respectively. The antibacterial efficacy of the deposited hydroxyapatite coatings was confirmed using the modern technique of fluorescence-activated cell sorting. Finally, the bioactivity of hydroxyapatite coatings was investigated by conducting immersion test in simulated body fluid environment. The scanning electron microscopy and atomic force microscopy results revealed higher (∼8 nm) average surface roughness, which is likely to facilitate better osseointegration. X-ray diffraction analysis confirmed that postdeposition annealing is essential to achieve the desired crystallinity and uniformity of coatings. Tensile pull-out tests confirmed adhesive strength of hydroxyapatite coatings beyond the standard expected values. Immersion tests inferred high bioactivity of pulsed laser deposition hydroxyapatite coatings. The promising results obtained in this research signify the potential application of hydroxyapatite coatings in orthopedic implants.
25
Magnani, Giuseppe, Paride Fabbri, Enrico Leoni, Elena Salernitano, and Francesca Mazzanti. "New Perspectives on Zirconia Composites as Biomaterials." Journal of Composites Science 5, no. 9 (September 11, 2021): 244. http://dx.doi.org/10.3390/jcs5090244.
Full textAbstract:
Zirconia–alumina composites couple the high toughness of zirconia with the peculiar properties of alumina, i.e., hardness, wear, and chemical resistance, so they are considered promising materials for orthopedic and dental implants. The design of high performance zirconia composites needs to consider different aspects, such as the type and amount of stabilizer and the sintering process, that affect the mechanics of toughening and, hence, the mechanical properties. In this study, several stabilizers (Y2O3, CuO, Ta2O5, and CeO2) were tested together with different sintering processes to analyze the in situ toughening mechanism induced by the tetragonal–monoclinic (t–m) transformation of zirconia. One of the most important outcomes is the comprehension of the opposite effect played by the grain size and the tetragonality of the zirconia lattice on mechanical properties, such as fracture toughness and bending strength. These results allow for the design of materials with customized properties and open new perspectives for the development of high-performance zirconia composites for orthopedic implants with high hydrothermal resistance. Moreover, a near-net shape forming process based on the additive manufacturing technology of digital light processing (DLP) was also studied to produce ceramic dental implants with a new type of resin–ceramic powder mixture. This represents a new frontier in the development of zirconia composites thanks to the possibility to obtain a customized component with limited consumption of material and reduced machining costs.
26
Johnson, Ian, Qiaomu Tian, and Huinan Liu. "Nanostructured Ceramic and Ceramic-Polymer Composites as Dual Functional Interface for Bioresorbable Metallic Implants." MRS Proceedings 1621 (2014): 39–45. http://dx.doi.org/10.1557/opl.2014.344.
Full textAbstract:
ABSTRACTMillions of medical implants and devices (e.g., screws, plates, and pins) are used each year worldwide in surgery, and traditionally the components have been limited to permanent metals (e.g., stainless steel, titanium alloys) and polyester-based absorbable polymers. Because of clinical problems associated with these traditional materials, a novel class of biodegradable metallic materials, i.e., magnesium-based alloys, attracted great attention and clinical interests. Magnesium (Mg) is particularly attractive for load-bearing orthopedic applications because it has comparable modulus and strength to cortical bone. Controlling the interface of Mg with the biological environment, however, is the key challenge that currently limits this biodegradable metal for broad applications in medical devices and implants. This paper will particularly focus on creating nanostructured interface between the biodegradable metallic implant and surrounding tissue for the dual purposes of (1) mediating the degradation of the metallic implants and (2) simultaneously enhancing bone tissue regeneration and integration. Nanophase hydroxyapatite (nHA) is an excellent candidate as a coating material due to its osteoconductivity that has been widely reported. Applying nHA coatings or nHA containing composite coatings on Mg alloys is therefore promising in serving the needed dual functions. The composite of nHA and poly(lactic-co-glycolic acid) (PLGA) as a dual functional interface provides additional benefits for medical implant applications. Specifically, the polymer phase promotes interfacial adhesion between the nHA and Mg, and the degradation products of PLGA and Mg neutralize each other. Our results indicate that nHA and nHA/PLGA coatings slow down Mg degradation rate and enhance adhesion of bone marrow stromal cells, thus promising as the next-generation multifunctional implant materials. Further optimization of the coatings and their interfacial properties are still needed to bring them into clinical applications.
27
Hamweendo, Agripa, Lebogang Moloisane, and Ionel Botef. "Bio-Mechanical Compatibility Assessment of Titanium-Nickel Alloy Fabricated Using Cold Spray Process." Materials Science Forum 828-829 (August 2015): 351–56. http://dx.doi.org/10.4028/www.scientific.net/msf.828-829.351.
Full textAbstract:
This paper presents the bio-mechanical compatibility assessment of Titanium-Nickel (TiNi) alloy fabricated using cold spray (CS) process. This research creates opportunity for meeting the increased demand for biomedical implants in orthopedic surgeries brought by sport and traffic related bone injuries. Due to their exceptional properties, TiNi alloys are promising alternative biomedical materials to the traditional Ti6Al4V alloys. Studies show that the conventional methods for producing TiNi alloys have several challenges. As a contribution towards resolving this problem, this paper studied the bio-mechanical properties of Ti and TiNi structures fabricated using CS process. The results of this study show that the porosity, incipient Young’s modulus, and tensile strength of TiNi and Ti coatings are close to the required values for the biomedical implants. Consequently, this research demonstrates that porous TiNi and Ti structures fabricated by CS are possible candidates for biomedical implants and that CS could be a new process for fabricating near-net shape bio-mechanical compatible materials.
28
Zaharin, Haizum, Ahmad Abdul Rani, Farooq Azam, Turnad Ginta, Nabihah Sallih, Azlan Ahmad, Nurul Yunus, and Tun Zulkifli. "Effect of Unit Cell Type and Pore Size on Porosity and Mechanical Behavior of Additively Manufactured Ti6Al4V Scaffolds." Materials 11, no. 12 (November 28, 2018): 2402. http://dx.doi.org/10.3390/ma11122402.
Full textAbstract:
Porous metal structures have emerged as a promising solution in repairing and replacing damaged bone in biomedical applications. With the advent of additive manufacturing technology, fabrication of porous scaffold architecture of different unit cell types with desired parameters can replicate the biomechanical properties of the natural bone, thereby overcoming the issues, such as stress shielding effect, to avoid implant failure. The purpose of this research was to investigate the influence of cube and gyroid unit cell types, with pore size ranging from 300 to 600 µm, on porosity and mechanical behavior of titanium alloy (Ti6Al4V) scaffolds. Scaffold samples were modeled and analyzed using finite element analysis (FEA) following the ISO standard (ISO 13314). Selective laser melting (SLM) process was used to manufacture five samples of each type. Morphological characterization of samples was performed through micro CT Scan system and the samples were later subjected to compression testing to assess the mechanical behavior of scaffolds. Numerical and experimental analysis of samples show porosity greater than 50% for all types, which is in agreement with desired porosity range of natural bone. Mechanical properties of samples depict that values of elastic modulus and yield strength decreases with increase in porosity, with elastic modulus reduced up to 3 GPa and yield strength decreased to 7 MPa. However, while comparing with natural bone properties, only cube and gyroid structure with pore size 300 µm falls under the category of giving similar properties to that of natural bone. Analysis of porous scaffolds show promising results for application in orthopedic implants. Application of optimum scaffold structures to implants can reduce the premature failure of implants and increase the reliability of prosthetics.
29
Gabay, Noa, Tomer Ron, Razi Vago, Amnon Shirizly, and Eli Aghion. "Evaluating the Prospects of Ti-Base Lattice Infiltrated with Biodegradable Zn–2%Fe Alloy as a Structural Material for Osseointegrated Implants—In Vitro Study." Materials 14, no. 16 (August 19, 2021): 4682. http://dx.doi.org/10.3390/ma14164682.
Full textAbstract:
The term “osseointegrated implants” mainly relates to structural systems that contain open spaces, which enable osteoblasts and connecting tissue to migrate during natural bone growth. Consequently, the coherency and bonding strength between the implant and natural bone can be significantly increased, for example in operations related to dental and orthopedic applications. The present study aims to evaluate the prospects of a Ti–6Al–4V lattice, produced by selective laser melting (SLM) and infiltrated with biodegradable Zn2%Fe alloy, as an OI–TiZn system implant in in vitro conditions. This combined material structure is designated by this study as an osseointegrated implant (OI–TiZn) system. The microstructure of the tested alloys was examined both optically and using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The mechanical properties were assessed in terms of compression strength, as is commonly acceptable in cases of lattice-based structures. The corrosion performance was evaluated by immersion tests and electrochemical analysis in terms of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS), all in simulated physiological environments in the form of phosphate buffered saline (PBS) solution. The cytotoxicity was evaluated in terms of indirect cell viability. The results obtained demonstrate the adequate performance of the OI–TiZn system as a non-cytotoxic structural material that can maintain its mechanical integrity under compression, while presenting acceptable corrosion rate degradation.
30
Fan, Mei, Fei Zhao, Yuan Liu, Sheng Yin, Shanshan Peng, and Zongkui Zhang. "Zinc Matrix Composites Reinforced with Partially Unzipped Carbon Nanotubes as Biodegradable Implant Materials." Crystals 12, no. 8 (August 8, 2022): 1110. http://dx.doi.org/10.3390/cryst12081110.
Full textAbstract:
The activity of zinc is between that of magnesium and iron, and it has a suitable degradation rate and good biocompatibility. It has been regarded as a very promising biodegradable metal material for biomedicine. However, the insufficient mechanical properties of pure Zn limit its practical application in the field of orthopedic implants. In this paper, partially unzipped carbon nanotubes (PUCNTs) obtained by meridionally cutting multi-walled carbon nanotubes (MWCNTs) were used as reinforcements and combined with spark plasma sintering to prepare partially unzipped carbon nanotube reinforced Zn matrix composites. The effects of PUCNT addition on the microstructure and the mechanical properties of Zn matrix composites were investigated. The microstructure analysis showed the good interface bonding between PUCNTs and the Zn matrix. Additionally, the strength of PUCNTs/Zn composites showed a trend of increasing first and then decreasing with the PUCNT content increases. When the PUCNT content was 0.2 wt%, the tensile strength and yield strength of composites were about 78.4% and 64.4% higher than that of pure Zn, respectively, while maintaining a high elongation (62.6%).
31
S. Williamson, Randall. "PEEK as a Potential Material for Dental Implants and its Biomechanical Properties and Osteoblast Cell Response." Journal of Dentistry and Oral Epidemiology 1, no. 2 (November 23, 2021): 1–11. http://dx.doi.org/10.54289/jdoe2100106.
Full textAbstract:
Proper osseointegration is crucial for the success of dental and orthopedic implants. Titanium-6Aluminum-4Vanadium (TAV) is one of the most popular implant materials; however, polyetheretherketone (PEEK) has gained the interest of implant researchers and manufacturers over the past several years due to its lower modulus of elasticity compared to metallic implant materials. Porosity and patterned surface morphologies are thought to improve mechanical interlocking and play an important role in the differentiation of pre-osteoblasts into mature osteoblasts. This study aimed to determine the effects a macro patterned PEEK surface has on the material’s mechanical properties and the proliferation, differentiation, and maturation of pre-osteoblasts. Mechanical testing data indicated that the macro patterning improved the mechanical interlocking and has no detrimental effect on compression strength. DNA data and live/dead imaging showed that pre-osteoblasts on solid PEEK specimens did not readily differentiate but instead encouraged proliferation only. However, ALP data in comparison to the DNA data showed that cells on patterned PEEK specimens more readily entered the differentiation pathway to mineralization. This is further confirmed by the patterned PEEK specimens showing an overall higher amount of cell mineralization. Clinical significance: This study concludes that surface macro patterning of PEEK material increases the mechanical interlocking and enhances the osseointegration capability without diminishing mechanical properties.
32
Saberi, Abbas, Hamid Reza Bakhsheshi-Rad, Ahmad Fauzi Ismail, Safian Sharif, Mahmood Razzaghi, Seeram Ramakrishna, and Filippo Berto. "The Effect of Co-Encapsulated GO-Cu Nanofillers on Mechanical Properties, Cell Response, and Antibacterial Activities of Mg-Zn Composite." Metals 12, no. 2 (January 22, 2022): 207. http://dx.doi.org/10.3390/met12020207.
Full textAbstract:
Magnesium-based composites have recently been studied as biodegradable materials for preparing orthopedic implants. In this article, the graphene oxide (GO) and GO-Cu nanosystem has been homogenously dispersed as a reinforcement in the matrix of Mg-Zn (MZ) alloy using the semi powder metallurgy (SPM) method, and subsequently, the composite has been successfully manufactured using the spark plasma sintering (SPS) process. GO and GO-Cu reinforced composite displayed a higher compressive strength (~55%) than the unreinforced Mg-Zn sample. GO and GO-Cu dual nanofillers presented a synergistic effect on enhancing the effectiveness of load transfer and crack deflection in the Mg-based matrix. Besides, the GO-Cu dual nanofillers displayed a synergistic influence on antibacterial activity through combining the capturing influences of GO nanosheets with the killing influences of Cu. However, electrochemical and in-vitro immersion evaluation showed that Cu-GO reinforcement had a slightly negative effect on the corrosion behavior of the Mg-Zn sample, but the incorporation of GO enhanced corrosion resistance of the composite. Moreover, MZ/GO and MZ/GO-Cu nanocomposites showed acceptable cytotoxicity to MG-63 cells and revealed a high potential for use as an orthopedic implant material. Based on the research results, MZ/GO-Cu nanocomposite could be used in bone tissue engineering applications.
33
Kinash, Yu O., and L. V. Kinash. "CONCEPTUAL FEATURES OF OCCLUSAL BALANCE IN THE DEVELOPMENT AND PATHOLOGY OF LOCALIZED AND GENERALIZED DISEASES OF PARODONTAL TISSUES IN PATIENTS WITH PARTIAL TOOTH LOSS DURING ORTHOPEDIC REHABILITATION BOTH ON THE NATURAL TEETH AND THOSE ON DENTAL IMPLANT." Ukrainian Dental Almanac, no. 3 (September 30, 2022): 14–18. http://dx.doi.org/10.31718/2409-0255.3.2022.03.
Full textAbstract:
The biomechanical component is an important aspect of orthopedic rehabilitation in the case of parodontal tissue pathology, which involves the most accurate reproduction of not only the shape of the tooth but also the location (functional axis) and the relationships of occlusal surfaces. At the same time, it is important to understand that the functional axis of the tooth and the areas of occlusal contacts are very dynamic and depend on the strength and character of masticatory movements. Therefore, the force vectors on the tooth axis continuously change in the articulation cycle, which helps to change the force of the occlusal interaction of the dentitions and the direction on the periodontium itself and the bone tissue of the jaws.
Aim: To explain the importance of restoration of functional occlusal relationships in patients with localized and generalized diseases of parodontal tissues, on the example of partial tooth loss with rational orthopedic rehabilitation on natural teeth and dental implants.
Materials and methods. Clinical examination of patients with localized and generalized parodontal tissue diseases. Orthopantomography – for visualization of the general state of the dentofacial system. In complicated cases, computer tomography with 3D replication was used to make a diagnosis and choose a treatment method. Adjustable articulators have been configured for individual functions together with CAD/CAM technology for the production of rational orthopedic restorations.
Study results and discussion. 10 patients after orthopedic treatment (13 orthopedic restorations on their natural abutment teeth and dental implants) were admitted to the Dental Medical Center of Danylo Halytsky Lviv National Medical University with complaints of difficult mastication, increased mobility of orthopedic restorations, and halitosis. During clinical examination and taking history, it was found that all patients with parodontal tissue pathology underwent local orthopedic treatment on their natural abutment teeth consisting of 3 bridgework (23% (p<0.05)) and 4 single (31% (p<0.05)) orthopedic restorations and 9 dental implants, which corresponded to 3 bridgework (23% (p<0.05)) and 3 single (23% (p<0.05)) orthopedic restorations, which were used from 6 to 12 months. The signs of disocclusion and overloading were found on the laterotrusion side when checking the static and dynamic occlusion according to the concepts of group management and canine protection. As a result of orthopedic rehabilitation in a virtual articulator adjusted for individual function, functional occlusion was normalized, pathological dental mobility, signs of peri-implantitis, and inflammatory processes of the supporting teeth were eliminated for 10 patients (13 orthopedic restorations) with localized and generalized diseases of parodontal tissues and partial loss of teeth. After 12 months, control clinical examination with additional examination methods of patients with parodontal tissue pathology corresponded to the stabilization of the pathological process both on their natural abutment teeth and on dental implants with normative osseointegration.
Conclusion. Therefore, the shape and size of restored functional occlusal relationships in adjustable articulators configured for individual function using modern CAD/CAM technologies ensure the balancing of force vectors on teeth and dental implants in parodontal tissue pathology.
Directions for future research. Unfortunately, modern technologies are not available to all patients and medical institutions of health care of Ukraine due to their high cost. Consequently, a significant number of orthopedic restorations are manufactured in commercial technical laboratories or manually by dental technicians in municipal health care facilities. Therefore, scientific publications must be aimed at attracting and implementing modern technologies in health care educational institutions for further scientific and practical development.
34
Scripcaru, Andrei, Norin Forna, Alexandru Bogdan Ciubara, Horea Rares Ciprian Benea, Vlad Veringa, Mihnea Theodor Sirbu, Razvan Tudor, and Paul-Dan Sirbu. "The Advantages of Bioresorbable INION� Implants in Traumatology Design, polymer composition and preliminary results." Materiale Plastice 56, no. 1 (March 30, 2019): 47–50. http://dx.doi.org/10.37358/mp.19.1.5120.
Full textAbstract:
Some disadvantages of traditional metallic implants used in orthopedics and traumatology prompted the development of bioresorbable polymer devices.The aim of this experimental study is to emphasize the characteristics of INION� resorbable implants (regarding design and polymers compositions), as well as to evaluate the results when using these innovative implants in two trauma cases. The polymers used in manufacturing INION� devices (Trimethylene Carbonate/TMC; L-Polylactic acid/LPLA; D,L Polylactic acid/DLPLA; Polyglycolic acid/PGA) degrade in alpha-hydroxy acids, gradually losing their hardness in 18-36 weeks with a complete bioresorption of 2-4 years. The clinical cases demonstrated the advantages of INION� plates (adapted shape, low profile, polyaxial screws, acceptable strength) or pins (allowing the aligmment and fixation of fracture, no migration). Among our patients, we found excellent results concerning the maintaining of primary reduced fracture, active range of motion, minimal pain with improving everyday comfort, no tissue or implant complications. Bioresorbable fracture fixation INION� devices are a viable alternative to traditional metallic implants, offering same significant advantages over them: the avoidance of long-term interference with gliding structures, keeping their strength long enough to support bone healing, no need to remove the implants, less pain, radiolucency, elimination of stress shielding and a lower risk of complications.
35
Kuffner, Bruna Horta Bastos, Patricia Capellato, Larissa Mayra Silva Ribeiro, Daniela Sachs, and Gilbert Silva. "Production and Characterization of a 316L Stainless Steel/β-TCP Biocomposite Using the Functionally Graded Materials (FGMs) Technique for Dental and Orthopedic Applications." Metals 11, no. 12 (November 29, 2021): 1923. http://dx.doi.org/10.3390/met11121923.
Full textAbstract:
Metallic biomaterials are widely used for implants and dental and orthopedic applications due to their good mechanical properties. Among all these materials, 316L stainless steel has gained special attention, because of its good characteristics as an implantable biomaterial. However, the Young’s modulus of this metal is much higher than that of human bone (~193 GPa compared to 5–30 GPa). Thus, a stress shielding effect can occur, leading the implant to fail. In addition, due to this difference, the bond between implant and surrounding tissue is weak. Already, calcium phosphate ceramics, such as beta-tricalcium phosphate, have shown excellent osteoconductive and osteoinductive properties. However, they present low mechanical strength. For this reason, this study aimed to combine 316L stainless steel with the beta-tricalcium phosphate ceramic (β-TCP), with the objective of improving the steel’s biological performance and the ceramic’s mechanical strength. The 316L stainless steel/β-TCP biocomposites were produced using powder metallurgy and functionally graded materials (FGMs) techniques. Initially, β-TCP was obtained by solid-state reaction using powders of calcium carbonate and calcium phosphate. The forerunner materials were analyzed microstructurally. Pure 316L stainless steel and β-TCP were individually submitted to temperature tests (1000 and 1100 °C) to determine the best condition. Blended compositions used to obtain the FGMs were defined as 20% to 20%. They were homogenized in a high-energy ball mill, uniaxially pressed, sintered and analyzed microstructurally and mechanically. The results indicated that 1100 °C/2 h was the best sintering condition, for both 316L stainless steel and β-TCP. For all individual compositions and the FGM composite, the parameters used for pressing and sintering were appropriate to produce samples with good microstructural and mechanical properties. Wettability and hemocompatibility were also achieved efficiently, with no presence of contaminants. All results indicated that the production of 316L stainless steel/β-TCP FGMs through PM is viable for dental and orthopedic purposes.
36
Pinc, Jan, Jaroslav Čapek, Vojtěch Hybášek, Filip Průša, Klára Hosová, Jan Maňák, and Dalibor Vojtěch. "Characterization of Newly Developed Zinc Composite with the Content of 8 wt.% of Hydroxyapatite Particles Processed by Extrusion." Materials 13, no. 7 (April 6, 2020): 1716. http://dx.doi.org/10.3390/ma13071716.
Full textAbstract:
Zinc and its alloys belong to a group of biodegradable materials, which can be potentially used for the preparation of temporary orthopedic implants. The research of biodegradable zinc materials revealed a lot of limitations; however, the new processing approaches of those materials can enhance their properties, which are insufficient for now. In this study, the zinc composite with 8 wt.% of hydroxyapatite (Zn/HA8) prepared for the first time by extrusion process was characterized from the point of view of the structural, mechanical and corrosion properties. The extrusion process led to good integrity of the interfaces between the zinc and hydroxyapatite particles. Mechanical behavior confirmed the role of hydroxyapatite as a defect in the material structure, which led to a decrease of the Zn/HA8 mechanical properties by approximately 30% (compressive yield strength (CYS) = 154 MPa Zn, 113 MPa Zn/HA8). Despite that, the Zn/HA8 composite showed sufficient mechanical properties for cancellous bone replacement and reached the lower limit for cortical bone. Additionally, the presence of hydroxyapatite caused the preferential precipitation of hydroxyapatite (HA) from the solution and can lead to a significant enhancement of the tissue/implant interface interactions.
37
Rerikh, V. V., and V. D. Sinyavin. "Bioactivity Experimental Studies of Composite Materials Promising for Use in Traumatology and Orthopedics: Review." Traumatology and Orthopedics of Russia 27, no. 1 (April 15, 2021): 97–105. http://dx.doi.org/10.21823/2311-2905-2021-27-1-97-105.
Full textAbstract:
The aim of the study — to determine the properties of modern bioactive composite materials that have the greatest advantage for use in traumatology and orthopedics, particularly in spine surgery.Material and Methods. We performed a comprehensive literature search using PubMed, Medline, eLIBRARY and Semantic Scholar. The keywords “implants”, “biomaterials”, “composites”, “tissue engineering”, “scaffolds”, “graphene”, “hydrogels”, “3D bioprinting” were used to identify papers examining the topic of interest. We included comparative studies published from 2010 to 2020 in our review. The following properties were evaluated in papers: biotolerance, bioactivity, osteoconductivity, osteoinductivity, osteostimulation, mechanical strength.Results. Special attention is paid to the creation of composites. Composites are made by combining two or more materials to achieve biochemical and biomechanical properties. In composites production, a certain place is occupied by the technology of 3D bioprinting, thanks to which it is possible to develop an individual implant according to a given situation.Conclusion. The combination of composite materials properties indicating on their bioactivity and mechanical strength, as well as the use of 3D techniques to design the geometric forms of implants, provide a high potential for use in traumatology and orthopedics, particularly in spinal surgery.
38
Filho, Francisco Pinto, Crislene Rodrigues da Silva Morais, Karla Valéria Miranda de Campos, José Jefferson da Silva Nascimento, and Josué da Silva Burit. "Chemical, Structural and Mechanical Study of Metallic Biomaterials Used in Hip Arthroplasty." Materials Science Forum 802 (December 2014): 507–11. http://dx.doi.org/10.4028/www.scientific.net/msf.802.507.
Full textAbstract:
Arthroplasty is a surgery that aims to replace the defective joint surfaces, aiming to restore their functions. Is employed in this type of surgery that metallic materials play a key role in the constitution of orthopedic prostheses. In this context, we studied the chemical composition, mechanical and structural behavior of stainless steel developed for applications as biomaterials used in the manufacture of orthopedic implants. In this paper, two prostheses were analyzed established brands in the market. Proceeded through the chemical Spectroscopy Energy Dispersive X-ray (EDX) analysis. Characterized the crystal structures of these materials by diffraction of X-ray and mechanical behavior using tensile test. We compared the results of chemical composition and strength of the samples according to ASTM F-138 (2008). The results of EDX showed the presence of chloride in stainless steel alloys as an impurity that can compromise the durability of the prosthesis. The XRD patterns showed the presence in austenitic stainless steel alloys. As the tensile strength of the alloys analyzed, values that are consistent with those presented in the standards were recorded. In a general analysis, it became apparent incompatibility of assessed as biomaterials for use in prosthetic alloys, although meets the structural and mechanical requirements.
39
Mozumder, Mohammad Sayem, Abdel-Hamid I. Mourad, Hiran Perinpanayagam, and Jesse Zhu. "NanoTiO2-Enriched Biocompatible Polymeric Powder Coatings: Adhesion, Thermal and Biological Characterizations." Advanced Materials Research 995 (July 2014): 113–24. http://dx.doi.org/10.4028/www.scientific.net/amr.995.113.
Full textAbstract:
The success of orthopedic and dental implants largely depends on their biocompatibility with the surrounding body environment and the biocompatibility depends on the physical, chemical, mechanical, topographical and biological properties of the implant materials chosen. Since the last few decades, titanium and its alloys have been among the most widely used ones due to their superior biocompatibility and mechanical properties; however, pure titanium needs to be pre and/or post treated chemically or physically to maintain appropriate textures and surface roughness. In the present study, TiO2 nanoparticles incorporated polymeric powder coatings consisting of smooth and micro-nanoscale roughness were developed that exhibited biocompatibility towards Human Embryonic Palatial Mesenchymal (HEPM) Cells. In addition, an experimental set up was designed and executed to evaluate the adhesion/ bond strength of the coating and to measure the load bearing capacity that the coatings can withstand before being detached from the substrate. Coating’s topographical features were analyzed by using Scanning Electron Microscopy (SEM). Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were performed to evaluate the thermal stability of the coating materials.
40
Li, Yankun, Rui Luo, Quanming Zhao, Tao Guo, Jieshi Wu, Zhi Peng, Bo Wang, Ruisheng Xu, and Chuan Ye. "Preparation and characterization of cobalt–titanium dioxide on the surfaces of titanium implants." Materials Express 12, no. 7 (July 1, 2022): 878–85. http://dx.doi.org/10.1166/mex.2022.2234.
Full textAbstract:
Titanium and its alloys are widely used in orthopedic implant materials due to their excellent mechanical properties and good biocompatibilities. However, titanium lacks biological activity and is prone to complications, such as loosening and sinking after implantation. Modifying the surface of titanium can improve its biological activity. In this study, we prepared a cobalt–titania (Co–TiO2) coating on a titanium surface by means of micro-arc oxidation technology. Scanning electron microscopy (SEM), atomic force microscopy (AFM), X-ray diffraction (XRD), X-ray photoelectron energy spectrometry (XPS) and automatic scratch tests were used to check the bond strength of the coating. The surface morphology and structure of the modified coating were characterized; the results showed that when the micro-arc oxidation electrolyte solution contained cobalt gluconate, cobalt was successfully introduced into the titanium surface, the coating exhibited a porous morphology, the elemental cobalt was evenly distributed in the coating, and the introduced cobalt did not change the surface morphology and phase composition of the coating. The scratch tests showed that the coating was strongly bonded with the substrate. In conclusion, Co–TiO2 coatings can be prepared on the surfaces of titanium implants by micro-arc oxidation. The coatings showed good surface characteristics and potential clinical application value.
41
Kempfert, Merle, Elmar Willbold, Sebastian Loewner, Cornelia Blume, Johannes Pitts, Henning Menzel, Yvonne Roger, Andrea Hoffmann, Nina Angrisani, and Janin Reifenrath. "Polycaprolactone-Based 3D-Printed Scaffolds as Potential Implant Materials for Tendon-Defect Repair." Journal of Functional Biomaterials 13, no. 4 (September 23, 2022): 160. http://dx.doi.org/10.3390/jfb13040160.
Full textAbstract:
Chronic tendon ruptures are common disorders in orthopedics. The conventional surgical methods used to treat them often require the support of implants. Due to the non-availability of suitable materials, 3D-printed polycaprolactone (PCL) scaffolds were designed from two different starting materials as suitable candidates for tendon-implant applications. For the characterization, mechanical testing was performed. To increase their biocompatibility, the PCL-scaffolds were plasma-treated and coated with fibronectin and collagen I. Cytocompatibility testing was performed using L929 mouse fibroblasts and human-bone-marrow-derived mesenchymal stem cells. The mechanical testing showed that the design adaptions enhanced the mechanical stability. Cell attachment was increased in the plasma-treated specimens compared to the control specimens, although not significantly, in the viability tests. Coating with fibronectin significantly increased the cellular viability compared to the untreated controls. Collagen I treatment showed an increasing trend. The desired cell alignment and spread between the pores of the construct was most prominent on the collagen-I-coated specimens. In conclusion, 3D-printed scaffolds are possible candidates for the development of tendon implants. Enhanced cytocompatibility was achieved through surface modifications. Although adaptions in mechanical strength still require alterations in order to be applied to human-tendon ruptures, we are optimistic that a suitable implant can be designed.
42
Asrar, Shafaq, Ambreen Azmat, Iftikhar Ahmed Channa, Jaweria Ashfaq, Faraz Sufyan, Sarmad Feroze, Ali Dad Chandio, Muhammad Ali Shar, and Abdulaziz Alhazaa. "Comparative Study of TiMn and TiAlV Alloys via the Nanoindentation Technique." Crystals 12, no. 11 (October 28, 2022): 1537. http://dx.doi.org/10.3390/cryst12111537.
Full textAbstract:
There are two common categories of implants that are used in medical sciences, i.e., orthopedic and dental ones. In this study, dental implant materials are focused such as Ti6Al4V alloys that are used for the replacement of lost teeth due to their high strength and biocompatibility. However, they cause infections in nearby tissues due to elemental release (potentially Al and V). Thus, manganese is selected to be incorporated into the alloy since it is also present in the human body in the form of traces. Different sets of implants were produced, i.e., Ti5Mn and Ti10Mn (where 5 and 10 describe the percentage of Mn) by using the powder metallurgy technique. This was followed by characterization techniques, including X-ray fluorescence spectroscopy (XRF), X-ray diffractometer (XRD), optical microscope (OM), and nanoindenter. The very aim of this study is to compare the microstructural evolutions, density, and mechanical properties of reference alloys and the ones produced in this study. Results show the microstructure of Ti6Al4V consists of the alpha (α) and beta (β) phases, while Ti5Mn and Ti10Mn revealed the beta (β) phases. The Ti5Mn alloy showed excellent mechanical properties than that of the Ti6Al4V counterpart. Extensive discussion is presented in light of the observed results. The relative density of Ti5Mn alloy was found to be enhanced than that of reference alloy.
43
Pavlov, O. D., V. V. Pastukh, and M. Yu Karpinsky. "The problem of using composite biodegradable implants for the treatment of bone fractures (literature review)." TRAUMA 22, no. 2 (June 15, 2021): 5–16. http://dx.doi.org/10.22141/1608-1706.2.22.2021.231952.
Full textAbstract:
Diseases and injuries of the musculoskeletal system rank second among the causes of injuries and third among the diseases that lead to disability of the adult population. Orthopedic implants have a special place in both clinical practice and the biomedical industry. The implants capable of biodegrading in the case of their implantation into the human body are of the greatest interest. The concept of biodegra-dable implants appeared through the formation and development of the use of suture materials that are absorbed in the body. Subsequently, this type of material began to be used in the treatment of fractures, because in many cases, bone fragments need only temporary support with a fixator, until they fuse. Implantable internal fixation devices for fracture repair using polyglycolic acid (PGA), polylactic acid (PLA), and a copolymer of lactic acid and glycolide (PLGA) became popular. However, the mechanical properties of highly porous skeletons were relatively weak compared to those required for bone engineering. In the process of creating an optimal polymeric biodegradable material, it is necessary to overcome the contradiction between strength and biodegradation. PGA, providing high strength of fixation, degrade too quickly, and PLGA, having high crystallinity, slightly degrade, at the same time conceding on the durability of both PGA and biostable materials. Scientists are now working hard to develop composites from calcium phosphate and polymer, in particular hydroxyapatite and tricalсium phosphate (TCP). TCP with three polymorphic modifications, in particular α-TCP, β-TCP, and α'-TCP, is a well-known bioceramic substance for bone repair. β-TKP is attracting increasing attention due to its excellent biocompatibility, bioactivity, and biodegradability. The composite materials based on bioactive ceramics mainly refer to materials with additional advantages, such as biodegradable polymers and ceramics. At the same time, these composites are biocompatible, osteoconductive, mechanical strength and have osteogenic characteristics. At the same time, thanks to new manufacturing technologies that have emerged in recent years, these compo-site materials are the most promising in the field of bone defect repair. The treatment of fractures with implants is increasingly associated with composite materials. Biomaterials must have certain mechanical properties: biocompatibility, biodegradation, controlled rate biodegradation, good mechanical strength, and bioactivity. Biomaterials used in the treatment of bone fractures have to disintegrate over time, and the addition of nanofillers can slow down the rate of decay of the biodegradable composite.
44
Nocivin, Anna, Doina Raducanu, Bogdan Vasile, Corneliu Trisca-Rusu, Elisabeta Mirela Cojocaru, Alexandru Dan, Raluca Irimescu, and Vasile Danut Cojocaru. "Tailoring a Low Young Modulus for a Beta Titanium Alloy by Combining Severe Plastic Deformation with Solution Treatment." Materials 14, no. 13 (June 22, 2021): 3467. http://dx.doi.org/10.3390/ma14133467.
Full textAbstract:
The present paper analyzed the microstructural characteristics and the mechanical properties of a Ti–Nb–Zr–Fe–O alloy of β-Ti type obtained by combining severe plastic deformation (SPD), for which the total reduction was of εtot = 90%, with two variants of super-transus solution treatment (ST). The objective was to obtain a low Young’s modulus with sufficient high strength in purpose to use the alloy as a biomaterial for orthopedic implants. The microstructure analysis was conducted through X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM) investigations. The analyzed mechanical properties reveal promising values for yield strength (YS) and ultimate tensile strength (UTS) of about 770 and 1100 MPa, respectively, with a low value of Young’s modulus of about 48–49 GPa. The conclusion is that satisfactory mechanical properties for this type of alloy can be obtained if considering a proper combination of SPD + ST parameters and a suitable content of β-stabilizing alloying elements, especially the Zr/Nb ratio.
45
Zapata, Mayra Eliana Valencia, José Herminsul Mina Hernandez, Carlos David Grande Tovar, Carlos Humberto Valencia Llano, Blanca Vázquez-Lasa, Julio San Román, and Luis Rojo. "Osseointegration of Antimicrobial Acrylic Bone Cements Modified with Graphene Oxide and Chitosan." Applied Sciences 10, no. 18 (September 18, 2020): 6528. http://dx.doi.org/10.3390/app10186528.
Full textAbstract:
Acrylic bone cement (ABC) is one of the most used materials in orthopedic surgery, mainly for the fixation of orthopedic implants to the bone. However, ABCs usually present lack of biological activity and osseointegration capacity that leads to loosening of the prosthesis. This work reports the effect of introducing graphene oxide (GO) and chitosan (CS), separately or together, in the ABC formulation on setting performance, mechanical behavior, and biological properties. Introduction of both CS and GO to the ABC decreased the maximum temperature by 21% and increased the antibacterial activity against Escherichia coli by 87%, while introduction of only CS decreased bending strength by 32%. The results of cell viability and cell adhesion tests showed in vitro biocompatibility. The in vivo response was investigated using both subdermal and bone parietal implantations in Wistar rats. Modified ABCs showed absence of immune response, as confirmed by a normal inflammatory response in Wistar rat subdermal implantation. The results of the parietal bone implantation showed that the addition of CS and GO together allowed a near total healing bone–cement interface, as observed in the micrographic analysis. The overall results support the great potential of the modified ABCs for application in orthopedic surgery mainly in those cases where osseointegration is required.
46
Park, Ji-Won, Jin-Uk Hwang, Jong-Ho Back, Seong-Wook Jang, Hyun-Joong Kim, Pan-Seok Kim, Seunghan Shin, and Taejin Kim. "High strength PLGA/Hydroxyapatite composites with tunable surface structure using PLGA direct grafting method for orthopedic implants." Composites Part B: Engineering 178 (December 2019): 107449. http://dx.doi.org/10.1016/j.compositesb.2019.107449.
Full text
47
Kharin, Nikita, Pavel Bolshakov, and Alex G. Kuchumov. "Numerical and Experimental Study of a Lattice Structure for Orthopedic Applications." Materials 16, no. 2 (January 12, 2023): 744. http://dx.doi.org/10.3390/ma16020744.
Full textAbstract:
Prosthetic reconstructions provide anatomical reconstruction to replace bones and joints. However, these operations have a high number of short- and long-term complications. One of the main problems in surgery is that the implant remains in the body after the operation. The solution to this problem is to use biomaterial for the implant, but biomaterial does not have the required strength characteristics. The implant must also have a mesh-like structure so that the bone can grow into the implant. The additive manufacturing process is ideal for the production of such a structure. The study deals with the correlation between different prosthetic structures, namely, the relationship between geometry, mechanical properties and biological additivity. The main challenge is to design an endoprosthesis that will mimic the geometric structure of bone and also meet the conditions of strength, hardness and stiffness. In order to match the above factors, it is necessary to develop appropriate algorithms. The main objective of this study is to augment the algorithm to ensure minimum structural weight without changing the strength characteristics of the lattice endoprosthesis of long bones. The iterative augmentation process of the algorithm was implemented by removing low-loaded ribs. A low-loaded rib is a rib with a maximum stress that is less than the threshold stress. Values within the range (10, 13, 15, 16, 17, 18, 19 and 20 MPa) were taken as the threshold stress. The supplement to the algorithm was applied to the initial structure and the designed structure at threshold stresses σf = 10, 13, 15, 16, 17, 18, 19 and 20 MPa. A Pareto diagram for maximum stress and the number of ribs is plotted for all cases of the design: original, engineered and lightened structures. The most optimal was the designed “lightweight” structure under the condition σf = 17 MPa. The maximum stress was 147.48 MPa, and the number of ribs was 741. Specimens were manufactured using additive manufacturing and then tested for four-point bending.
48
de A. Mendes Filho, A. A., Vitor Luiz Sordi, and Maurizio Ferrante. "Optimization of Tensile Strength and Ductility of Grade 2 Ti, Conditioned by Severe Plastic Deformation." Materials Science Forum 667-669 (December 2010): 803–8. http://dx.doi.org/10.4028/www.scientific.net/msf.667-669.803.
Full textAbstract:
Among the materials employed for orthopedic implants, Ti-6Al-4V is definitely the best choice due to its excellent properties. However, a more intense use is hindered by high cost and the presence of harmful elements, viz. Al and V. A solution can be found in commercially pure Ti, provided its tensile and fatigue properties can be upgraded by some process of Severe Plastic Deformation. In the present work, Grade 2 Ti was submitted to up to four Equal Channel Angular Pressing passes, followed by cold rolling (30 70 and 90% reduction ratio) Hardness and tensile properties were determined, paying attention to the work hardening behavior. Results show that Severe Plastic Deformation gives a 442 MPa increase over the yield strength of annealed Grade 2 Ti (originally 337 MPa), while elongation reached 21%. Best results were obtained with four passes followed by 70% cold rolling reduction. Finally, the microstructural stability was assessed by hardness measurements.
49
Mohammed, Alaa A., Jawad K. Oleiwi, and Emad S. Al-Hassani. "The Effect of Nanoparticles (n-HAp, n-TiO<sub>2</sub>) on the Thermal Properties and Biomechanical Analysis of Polymeric Composite Materials for Dental Applications." Nano Hybrids and Composites 33 (October 11, 2021): 13–34. http://dx.doi.org/10.4028/www.scientific.net/nhc.33.13.
Full textAbstract:
Polyetheretherketone (PEEK), as implants is broadly employed in orthopedic and dental uses owing to the brilliant chemical stability, biocompatibility and mechanical strength in addition to the modulus of elasticity alike the human bone. In the present work, the composite materials with PEEK as matrix and (n-HAp, n-TiO2) as the reinforced fillers loaded up to (1.5 wt%) were prepared by internal mixer and hot press. Following analysis by physical properties includes the thermal conductivity and the differential scanning calorimetry. Finite element analysis (FEA) was used to find the total deformation, Max. Von mises stress, elastic strain and safety factor. The results manifested that the thermal properties, total deformation and strain decreased with the increase of the reinforcement weight fraction, while, the stress and safety factor increased with the increased reinforcement weight fraction.
50
Grecu, Dan, Dan Tarnita, Daniela Tarniţă, and D. R. Nita. "Our Experience with Alumina on Alumina Weight Bearing in Everyday Orthopedic Practice." Key Engineering Materials 614 (June 2014): 212–17. http://dx.doi.org/10.4028/www.scientific.net/kem.614.212.
Full textAbstract:
The research for an ideal hip prosthesis has led to the development of several durable materials that have been tested very intensly during the past decades, both clinically and mechanically. Alumina on alumina bearing has proven to be a very reliable bearing and is used more and more often. Nevertheless, because of the lack of ductility of alumina ceramic, concerns have been raised regarding its risk of fracture. The purpose of our study is to evaluate the mid-term results (78 months follow-up) of alumina on alumina prosthesis and the complications that have appeared regarding to the properties of the implant. We have reviewed retrospectively 89 THA performed in our clinic during October 2005 – October 2013 on a follow-up period of maximum 78 months. The mean age of the patients included was 49,60 years for men and 48,44 years for women. It was used a single kind of implant with same type of alumina parts, applied only on a postero-lateral surgical approach. The survival rate of ceramic-on-ceramic bearing surface by itself was 98.87% (88 out of 89). The most frequent complication was the dislocation of the prosthesis that happened in 7 cases, mainly due to a malposition of the acetabular cup, without any damage done to the ceramic bearing surfaces. In the failed case we have encountered a cracked femoral head that has been previously resterilized by steam. We could conclude that the alumina on alumina prosthesis is a very reliable prosthesis regarding its durability and strength. It requires a very precise surgical technique when implanted, since almost all the complications were due to a malposition of the acetabular component. A postero-lateral wall of the liner might decrease the rate of dislocations and ceramic wear. Also, we might debate that the steam sterilization is not suitable for alumina implants, since the fractured femoral head was resterilized.