Aspects Of Implantation Research Articles

Corrosion Prevention of Biomedical Implants: Surface Coating Techniques Perspective

AbstractNo doubt, the use of biomedical implants in the world has been of tremendous benefit to humans (animals as well), still gaining much relevance today, and commands greater prospects in the future. Developments in this field have been from the progression of the use of materials like wood, iron and gold as external limb support and indental applications, to more sophisticated materials today like biodegradable metal alloys, polymers, ceramics and composites materials capable of replacing damaged or worn‐out organs (eye, heart, lungs, liver, kidney, etc.), mimicking the bone, or for boosting other physiological features as in cosmetology.Appropriate applications of these implants in the human body still remain a challenge today due to several post‐surgical issues like cytotoxicity, thrombogenicity, allergenicity, carcinogenicity and inflammations all of which could be attributed to factors like biocompatibility, osseointegration, mechanical properties and corrosion resistance of these biomedical implants during service. The aspect of implants’ corrosion is of much concern in the biomedical industry of which there have been several methods used to tackle it viz ‐use of corrosion resistant materials and inhibitors, metal plating, environmental and design considerations and protective coating techniques. This paper reviews five different surface coating techniques for preventing corrosion in biomedical implants, their descriptions and working principles.

Comparison of In Vitro Biofilm Formation on Titanium and Zirconia Implants.

Peri-implant diseases are emerging issues in contemporary implant dentistry. As biofilms play a critical role in peri-implant diseases, the characteristic of resisting bacterial adhesion would be ideal for dental implants. The aims of the study were to compare titanium (Ti) and zirconia (Zr) implants regarding the amount of biofilm formation at different time frames and assess the distribution of biofilm on different aspects of dental implants. Biofilm was developed on Ti and Zr dental implants with a peri-implant-related multispecies model with Streptococcus oralis, Actinomyces naeslundii, Veillonella dispar, and Porphyromonas gingivalis, for 3 and 14 days. Quantitative assessment was performed with the measurement of total bacterial viability (colony forming units, CFU/mg). Scanning electron microscopy (SEM) was used to evaluate biofilm formation on different aspects of the implants. Three-day-old biofilm on Ti implants was significantly higher than that on Zr implants (p < 0.001). The Ti and Zr groups were not significantly different for 14-day-old biofilm. SEM images demonstrated that 3-day-old biofilm on Zr implants was sparse while biofilm growth was more pronounced for 3-day-old biofilm on Ti implants and 14-day-old biofilm groups. It appeared that less biofilm formed on the valley compared to the thread top for 3-day-old biofilm on Zr implants. Differences between the valley and the thread top became indistinguishable with the development of mature biofilm. While early formed biofilms show greater accumulation on Ti implants compared to Zr implants, older biofilms between the two groups are comparable. The distribution of biofilms was not uniform on different areas of implant threads during early biofilm development.

Mechanical and biological behaviour of porous Ti–SiO2 scaffold for tissue engineering application

The present work reports a cost-effective way of fabricating porous Titanium (Ti)/Silica (SiO2) composite scaffold with tailored pore microstructure through powder metallurgy technique, considering the aspect of implants where low bearing load is required with low elastic modulus. Rice husk (RH) powder of different size range was used as fugitive pore former and sucrose was used as a binder which also acted as a pore former. The porosity of the scaffold was controlled by varying the size and amount of space holder. After sintering, the developed composite scaffold was characterized through SEM, XRD, and EDS. Mechanical and biological testing of the scaffold were performed to determine mechanical and biological properties. The resulting scaffolds have the porosity in the range of 15–34%. The addition of silica from RH increased the compressive strength of the scaffold (116–396 MPa). It was also observed that due to the incorporation of pores in Ti matrix there was reduction in Elastic Modulus of the scaffold which is significantly important for Ti based implant materials. Bioactivity of the scaffold was examined by using SBF solution and it was found that the Ti/SiO2 scaffold has ability to form apatite layer. Antibacterial behaviour and biofilm formation on the surface of scaffold were also studied. Obtained result was compared with the properties of natural bone. It was found that the properties of the developed Ti/SiO2 composite scaffolds are similar to that of natural bone and hence can be suitable for orthopaedic application.

The role of microRNAs in ectopic pregnancy: A concise review.

Ectopic pregnancy (EP) is reported in about 1%–2% of pregnant females and is associated with mortality and morbidity. Several genetic and environmental factors might modulate occurrence of EP. Prediction of EP and patients' follow-up is an important task in management of pregnancy. MicroRNAs (miRNAs) as non-coding RNAs with sizes between 21 and 24 nucleotides have been shown to regulate several aspects of implantation and early fetal life. They have potential role in early detection of EP especially considering their presence in body fluids such as serum. Assessment of their expression in serum might provide a noninvasive method for diagnosis and patients' follow-up. However, data regarding their role in EP is not sufficient due to small sample sizes of the studies. Future studies are required to find miRNAs that regulate expression of EP-associated genes such as VEGFA, EGFR, ESR1 and immune response-related genes to provide new diagnostic biomarkers for EP.

Editorial introductions

Editorial introductions

Editorial introductions

Editorial introductions

Effect of O5+ ion implantation on the electrical and structural properties of Cu nanowires

Ion beam creates changes in the material along their track, not only embody the excellent properties but also tailor new materials. When the ions are implanted into the nanomaterials, they collide with the target atoms and interact through three different phenomena; electron collision, nuclear collision and charge exchange. In the present study, 1 MeV O5+ ions were implanted in copper nanowires of diameter 80 nm synthesized using template synthesis approach. Electrical and structural properties were recorded using Keithley 2400 series source meter and Rigaku X-ray diffractometer respectively, before and after the implantation. I–V characteristics showed the ohmic behavior with enhancement in conductivity of copper nanowires after implantation. No structural damage in the nanowires was revealed by XRD spectra. The work done can be viewed as a positive aspect of implantation in metallic nanowires especially in 80 nm diameter Cu nanowires and may be utilized to fabricate nanodevices.

Heart valve replacement: Which valve for which patient?

The ideal heart valve substitute would show no deterioration or thrombogenicity, offer no resistance to blood flow, and be easy to implant. However, such a valve does not exist and we must accept compromises in some of these qualities based on our patients' needs. In selection of cardiac valve prosthesis, valve-related factors such as durability, thrombogenicity, and fluid dynamics should be carefully matched to patient-related factors such as age, size, life expectancy, comorbidities, plans for pregnancy, and lifestyle. In addition, surgeon- or operation-related factors should be considered. Technical aspects of implantation, ease of reoperation, and operative mortalities may tip the risk and benefit balance in a particular direction. We review currently available heart valve prostheses and the clinical factors that are involved in selection of a heart valve substitute.

Chemical Aspects of Implantation of High‐Energy Ions into Polymeric Materials

AbstractFor Abstract see ChemInform Abstract in Full Text.

299 Reservoir system for bronchial arterial infusion against lung cancer patients: Part II — radiological and technical aspects of implantation of the system

299 Reservoir system for bronchial arterial infusion against lung cancer patients: Part II — radiological and technical aspects of implantation of the system

Effect of polyglycolic acid membrane on bone regeneration around titanium implants inserted in bone sockets

An experimental animal model was used to evaluate the value of resorbable, non-permeable polyglycolic acid (PGA) membranes in relation to fixtures implanted into simulated extraction sockets. Branemark fixtures (length 7.0 mm, diameter 3.75 mm) were implanted into edentulous areas of maxillary bone in six sheep. Five fixtures were covered with 0.15-mm-thick PGA membrane (Biofix®) held in place with a cover screw (PGA group) and five were implanted without membrane (control group). The animals were killed after 4 months and undecalcified mesiodistal sections were prepared from resected jaw specimens. Histomorphometry was used to measure the distance from the shoulder of the fixture to the level of intimate bone contact (SB distance). SB distance was found to be greater in the PGA than in the control group in relation both to the mesial (1.44 ± 0.88 mm versus 0.96 ± 0.47 mm) and distal (1.13 ± 0.80 mm versus 0.77 ± 0.63 mm) aspects of implants. This statistically not significant difference in bone regeneration between the two groups is related to the physical properties of the PGA membrane used.

Cellular and Molecular Aspects of Implantation. Proceedings of a Conference Held in Houston, Texas, September 17-19, 1979, Sponsored by the Center for Population Research, National Institute of Child Health and Human Development, and Other Bodies.Stanley R. Glasser , David W. Bullock

<i>Cellular and Molecular Aspects of Implantation. Proceedings of a Conference Held in Houston, Texas, September 17-19, 1979, Sponsored by the Center for Population Research, National Institute of Child Health and Human Development, and Other Bodies.</i>Stanley R. Glasser , David W. Bullock

Aspects of Implantation Cellular and Molecular Aspects of Implantation Stanley R. Glasser David W. Bullock

Aspects of Implantation Cellular and Molecular Aspects of Implantation Stanley R. Glasser David W. Bullock

International Conference on Cellular and Molecular Aspects of Implantation

International Conference on Cellular and Molecular Aspects of Implantation