PEEK Composite Scaffold Preparation for Load Bearing Bone Implants

2018 ◽  
Vol 911 ◽  
pp. 77-82
Author(s):  
Sivakoti Shyam Kumar ◽  
Rahul Chhibber ◽  
Rajeev Mehta
Keyword(s):  
Composite Scaffold ◽  
Selective Laser Sintering ◽  
Bone Collagen ◽  
Bone Implants ◽  
Load Bearing ◽  
Polyether Ether Ketone ◽  
Peek Composite ◽  
Egg Shells ◽  
Process Ability

Polyether ether ketone (PEEK), a thermoplastic polymer with remarkable mechanical properties apart from being bio-inert and approved by Food and Drug Administration-U S (FDA), is a promising bio-material at load bearing sites such as bone implants. The major challenge in PEEK associated bio composites is its process ability. Several ways have been attempted in past and finally resolved the issue by inkjet binder customized technique and Selective Laser Sintering for PEEK composite. An alternate method is presented in this work with ingenious process ability of PEEK, a polymer replacement for bone Collagen and Hydroxyapatites, the bone reinforcement prepared from egg shells. The alternate way suggested in this work is economically attractive without significant compromise in quality of the composite prepared.

3D-Printing Methods for Crystalline Polyetheretherketone

2020 ◽  
Vol 869 ◽  
pp. 466-473
Author(s):  
Kamila T. Shakhmurzova ◽  
Zhanna I. Kurdanova ◽  
Artur E. Baykaziev ◽  
Azamat Zhansitov ◽  
Svetlana Khashirova
Keyword(s):  
3D Printing ◽  
Literature Review ◽  
Material Properties ◽  
Selective Laser Sintering ◽  
Layer By Layer ◽  
Molten Polymer ◽  
Polyether Ether Ketone ◽  
Layer Deposition ◽  
Ether Ketone

The article is a literature review on 3D-printing of crystalline polyether ether ketone by the methods of layer-by-layer deposition of molten polymer filament (FDM) and selective laser sintering (SLS). The influence of printing technological modes and material properties (fluidity, morphology, etc.) on the quality of the products is considered.

scholarly journals Effect of Osteoporosis on Well-Integrated Bone Implants

2021 ◽  
Vol 11 (2) ◽  
pp. 723
Author(s):  
Amani M. Basudan ◽  
Marwa Y. Shaheen ◽  
Abdurahman A. Niazy ◽  
Jeroen J.J.P. van den Beucken ◽  
John A. Jansen ◽  
...  
Keyword(s):  
Dental Implants ◽  
Femoral Condyle ◽  
Bone Implants ◽  
Bone Implant ◽  
Ovx Rats ◽  
Bone Response ◽  
Significant Difference ◽  
Female Wistar Rats ◽  
Edentulous Patients

The installation of dental implants has become a common treatment for edentulous patients. However, concern exists about the influence of osteoporosis on the final implant success. This study evaluated whether an ovariectomy (OVX)-induced osteoporotic condition, induced eight weeks postimplantation in a rat femoral condyle, influences the bone response to already-integrated implants. The implants were inserted in the femoral condyle of 16 female Wistar rats. Eight weeks postimplantation, rats were randomly ovariectomized (OVX) or sham-operated (SHAM). Fourteen weeks later, animals were sacrificed, and implants were used for histological and histomorphometric analyses. A significant reduction in the quantity and quality of trabecular bone around dental implants existed in OVX rats in comparison to the SHAM group. For histomorphometric analysis, the bone area (BA%) showed a significant difference between OVX (34.2 ± 4.3) and SHAM (52.6 ± 12.7) groups (p < 0.05). Bone–implant contact (BIC%) revealed significantly lower values for all implants in OVX (42.5 ± 20.4) versus SHAM (59.0 ± 19.0) rats. Therefore, induction of an osteoporotic condition eight weeks postimplantation in a rat model negatively affects the amount of bone present in close vicinity to bone implants.

scholarly journals ANALYSIS OF THE CAUSES OF ACCIDENTS AT DIFFERENT STAGES OF LIFE CYCLE OF THE CONSTRUCTION OBJECT

2020 ◽  
pp. 17-22
Author(s):  
A. Lapina ◽  
A. Ponomarenko ◽  
K. Shencova ◽  
A. Kotesova
Keyword(s):  
Life Cycle ◽  
Russian Federation ◽  
Load Bearing ◽  
Life Cycle Design ◽  
The Russian Federation ◽  
Hydrogeological Studies ◽  
Construction Operation ◽  
Design Construction ◽  
Insufficient Number

the article deals with the main causes of accidents of buildings and structures that occurred due to errors made at different stages of their life cycle (design, construction, operation). A brief analysis of the accidents that occurred from 2010 to 2017 in the Russian Federation is presented. The study of the causes of accidents makes it possible to understand better the laws of structures, buildings and structures, to identify errors that lead to emergencies. Such errors include: low quality of construction and installation works, deviation from the project in the construction of buildings and structures, the use of materials of inadequate quality, overload of load-bearing structures during operation. Also, the causes of accidents include defective engineering-geological and hydrogeological studies of the grounds. Analysis of accidents showed that the last few years there is no tendency to reduce the number of accidents of buildings and structures, which indicates an insufficient number of measures to prevent them. In the article the authors consider the examples of accidents in construction, which occurred due to the main reasons, and ways to prevent accidents in the future.

scholarly journals Suplementasi Sari Belimbing Wuluh (Averrhoa bilimbi L.) dalam Air Minum terhadap Produktivitas Telur Puyuh

2020 ◽  
Vol 18 (2) ◽  
pp. 54-61
Author(s):  
Lylya Wahyuni ◽  
M R Ramdani ◽  
N O Imama ◽  
V E Larasati ◽  
A R Fahmi ◽  
...  
Keyword(s):  
Drinking Water ◽  
Egg Quality ◽  
Egg Yolk ◽  
Positive Control ◽  
Feed Conversion ◽  
Physical Quality ◽  
Randomized Design ◽  
Egg Shells ◽  
Haugh Unit

Supplementation of Averrhoa bilimbi L. juice which contains vitamin C and organic acid in drinking water has been proposed to reduce the effect of heat stress on the quail layer.  So this is expected to increase the productivity of quail and their egg quality. The aim of this research was to determine the effect of A. bilimbi juice supplementation in quail drinking water on quail performance,  physical quality of egg, and egg yolk antioxidant level. Two hundred and forty birds aged 4-5 weeks were maintained for 42 days. A Completely Randomized Design was used in this study with 4 treatments. Each treatment has 4 replications and 15 quails in each replications. Addition of Vita Chick (P0) to the drinking water was used as a positive control. The treatments given were the addition of A. bilimbi extract with different levels of 0% (P1), 2.5% (P2), and  5% (P3) respectively. The variables observed were quail performance, physical egg quality, and egg yolk antioxidant levels. The results showed that the  physical quality of quail eggs obtained were the weight of albumen and egg shells did not different all treatments. The  addition of A. bilimbi juice in drinking water  has affected on the weight and percentage of albumen, eggshell, and Haugh Unit. The addition of 2.5% of A.bilimbi juice (P2)  had the lowest feed conversion ratio (FCR). However it showed the highest Haugh Unit number of the egg. There was no different effect of the highest dose of A. bilimbi juice (5%, P3) on the egg yolk antioxidant  activity and capacity (41.54%  and 23.91 ppm respectively).  It was concluded that supplementation of A. bilimbi juice in drinker water  could  changed to antistress drug commercial.

scholarly journals Effects of Thermal Cycle and Ultraviolet Radiation on 3D Printed Carbon Fiber/Polyether Ether Ketone Ablator

Aerospace ◽  
2020 ◽  
Vol 7 (7) ◽  
pp. 95
Author(s):  
Farhan Abdullah ◽  
Kei-ichi Okuyama ◽  
Akito Morimitsu ◽  
Naofumi Yamagata
Keyword(s):  
Mechanical Properties ◽  
Carbon Fiber ◽  
Uv Radiation ◽  
Thermal Cycle ◽  
Temperature Behavior ◽  
Heat Shield ◽  
Polyether Ether Ketone ◽  
Peek Composite ◽  
3D Printed ◽  
Ether Ketone

The extreme heating environment during re-entry requires an efficient heat shield to protect a spacecraft. The current method of manufacturing a heat shield is labor intensive. The application of 3D printing can reduce cost and manufacturing time and improve the quality of a heat shield. A 3D printed carbon fiber/polyether ether ketone (CF/PEEK) composite was proposed as a heat shield material. The aim was to develop a heat shield and the structural member as a single structure while maintaining the necessary recession resistance. Test samples were exposed to thermal cycles and ultraviolet (UV) radiation environment. Subsequently, a tensile test was performed to evaluate the effect of thermal cycle and UV radiation on the mechanical properties. The sample’s recession performance and temperature behavior were evaluated using an arc heated wind tunnel. Exposure to thermal cycle and UV radiation have limited effect on the mechanical properties, recession behavior and temperature behavior of 3D CF/PEEK. Results from the arc heating test showed an expansion of the sample surface and better recession resistance than other existing ablator materials. Overall, 3D CF/PEEK has excellent recession resistance while maintaining mechanical properties when exposed to high temperature, thermal cycle and UV radiation.

Novel niobium and silver toughened hydroxyapatite nanocomposites with enhanced mechanical and biological properties for load-bearing bone implants

2019 ◽  
Vol 15 ◽  
pp. 531-542 ◽  
Author(s):  
Pengbo Wei ◽  
Ju Fang ◽  
Liming Fang ◽  
Kefeng Wang ◽  
Xiong Lu ◽  
...  
Keyword(s):  
Biological Properties ◽  
Bone Implants ◽  
Load Bearing

Characterization of Dental Metal-Ceramic Interfaces of Heat Pressed Ceramics on Co-Cr Frameworks Obtained with Different Technologies

2018 ◽  
Vol 876 ◽  
pp. 25-30
Author(s):  
Liliana Porojan ◽  
Mihaela Bîrdeanu ◽  
Cristina Savencu ◽  
Sorin Porojan
Keyword(s):  
Cross Section ◽  
Selective Laser Sintering ◽  
Interface Strength ◽  
Noticeable Effect ◽  
Metal Ceramic ◽  
Dental Metal ◽  
Ceramic Restorations ◽  
Ceramic Interfaces

It is known that the quality of metal-ceramic restorations mainly depends on the interface strength. The aim of the study was to evaluate metal–ceramic interfaces of heat pressed ceramic on Co-Cr frameworks obtained with different technologies: melting-casting (CST), computerized milling (MIL), selective laser sintering (SLS) and selective laser melting (SLM). The microstructure of metal–ceramic interfaces and framework topography were characterized by scanning electron microscope (SEM). Sandblasted, polished surfaces and the cross section on the interfaces were observed. Sandblasted surfaces presented a uniform rough aspect and pronounced porous surface compared to that of polished surfaces and were better visible in SLS and SLM samples. The thickness of the veneer layer had a noticeable effect on the interface, because in the case of thicker veneers, cracks at the interfaces were visible for CST and MIL specimens. Considering the findings reported herein, some suggestions can be considered in practice, such as adaptation of the restorations morphology to the characteristics of the processed materials.

Evolution of Direct Selective Laser Sintering of Metals

2011 ◽  
Vol 383-390 ◽  
pp. 6252-6257
Author(s):  
Francesco Cardaropoli ◽  
Fabrizia Caiazzo ◽  
Vincenzo Sergi
Keyword(s):  
Complex Geometry ◽  
Selective Laser Sintering ◽  
Laser Sintering ◽  
Layer By Layer ◽  
Metal Powders ◽  
Additive Process ◽  
Operator Experience ◽  
Critical Phases ◽  
Time Required

Direct Metal Selective Laser Sintering (DMSLS) is a layer-by-layer additive process for metal powders, which allows quick production of complex geometry parts. The aim of this study is to analyse the improvement of DMSLS with “EOSINT M270”, the new laser sintering machine developed by EOS. Tests were made on sintered parts of Direct Metal 20 (DM20), a bronze based powder with a mean grain dimension of 20 μm. Different properties and accuracy were evaluated for samples manufactured with three different exposure strategies. Besides mechanical properties, the manufacturing process was also examined in order to evaluate its characteristics. The quality of laser sintered parts is too affected by operator experience and skill. Furthermore, critical phases are not automatic and this causes an extension of time required for the production. Due to these limitations, DMSLS can be used for Rapid Manufacturing, but it is especially suitable to few sample series.

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