صفحه اصلیگزارش آماریکتابخانه های مرکزیراهنماورود
رکورد قبلیرکورد بعدی
Title Proper : Synthesis and Characterization of Functionally Graded Titanium Dental Implant by 3D Printing
First Statment of Responsibility : Ahmed A. H. Hindy Hammadi
First Statment of Responsibility : احمد هندی
Subsequent Statement of Responsibility : Maryam Torshabi, Farzam Farahmand
Subsequent Statement of Responsibility : مریم ترشابی، فرزام فرحمند
Subsequent Statement of Responsibility : advisors Fahimeh Sadat Tabatabaei, Fereydoun Pourdanesh, Abdulhadi M. Abid
Subsequent Statement of Responsibility : استاد مشاور فهیمه سادات طباطبایی، فریدون پوردانش، عبدالهادی عبید
College : Shahid Beheshti of Medical Science, Dental School
Academic Year : 2017
degree : --
field of study : مواد دندانی
Abstract : Background: Porous structures, manufactured of a biocompatible metal, mimicking human bone structure are the future of implantology. Fully porous materials, however, suffer from certain drawbacks. To overcome these, gradient in structure can be prepared. With gradient in porosity, mechanical properties can be optimized to an appropriate value, implant can be attributed a similar gradient macrostructure as bone, and tissue adhesion may be promoted. Additive manufacturing by laser melting is able to produce gradient porosity constructs for dental implants.Objectives. In this study, we seek to investigate the possibility of producing a functionally graded titanium implant incorporating a gradient of porosity, from the inner dense core to the outer surface, by laser melting of titanium alloy powder. Methods. All the specimens were prepared by a selective laser melting (SLM) procedure using the Ti-6Al-4V ELI alloy powder with a particle size range of 5-55µm. Full dense specimens fabricated by SLM were used as control group. The other three types of gradient porosity model specimens all featured with a fully dense core and a partially sintered gradient porous out to surface using CAD design. Gradient latticed design was examined using the X-ray tomography. Static compressive strength was determined using a MTS bench. Digital Image Correlation (DIC) was used for accurate 2D and 3D measurements of the displacement on the specimens during static compression test. The morphological analyses of all surfaces including fracture surfaces were performed by SEM. The surface roughness was investigated using atomic force microscope (AFM). In an in vitro investigation, human periodontal ligament stem cells (hPDLSCs) were cultured on the dense (control) and porous 3D-printed Ti-6Al-4V ELI specimens to study morphology and viability and proliferation of the cells using SEM observation (after 1 days), and MTT assay (after 1 and 3 days). The results were analyzed using one-way ANOVA and Tukey’s post hoc test. A p value of <0.05 was considered statistically significant. Results. Characterization of the constructs revealed open interconnected gradient porosities. The original surface microstructure consisted of roughly spherical particles. Surface roughness analysis also show some limitations of the SLM process. Despite this finding, functionally graded titanium alloy retained its cyto-compatibility, as it was outlined by MTT assay. With introduced porosity, yield strength showed linear decrease in compression. The Young’s modulus of the fully dense material was (71.80±16.21Gpa); while that of the gradient porous samples were in the range of (29.20±6.27Gpa) to (26.96±2.02Gpa). The fracture surface showed a dimpled appearance typical of ductile fracture. There were no significant differences in each type of these data among the three types of gradient porosity models (p>0.05).Conclusion. In conclusion, 3D-printing proved to be an efficient mean of construction of titanium dental implants with a functionally graded material design would be better adapted to the elastic properties of the bone. Such implants could minimize stress shielding effects and might improve long-term performance.
Subject : Dental Implants, Functionally Graded Materials, Gradient Porosity, Selective Laser Melting (SLM), Three-Dimensional Printing.

ارسال پیغام

آمار سامانه

تعداد دانشگاه ها :63
تعداد پایان نامه ها:286041
آخرین بروزرسانی:۱۳۹۷/۱۰/۱۶
کاربران آنلاین:39
بازدید امروز:494
بازدید کل:2289261

تماس با ما

شهرک قدس، بلوار فرحزادی، بلوار ایوانک، ساختمان مرکزی وزارت بهداشت، درمان وآموزش پزشکی، بلوک A، طبقه ۱۳، معاونت تحقیقات و فناوری ، مرکز توسعه وهماهنگی اطلاعات وانتشارات علمی، گروه اطلاع رسانی پزشکی

تلفن تماس: 81454318-021

توجه

کلیه حقوق این وب سایت و مطالب آن متعلق به مرکز توسعه و هماهنگی اطلاعات و انتشارات علمی معاونت تحقیقات و فناوری وزارت بهداشت، درمان و آموزش پزشکی بوده و هر استفاده از مطالب آن با ذکر منبع بلامانع است

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