Alumina is a ceramic bio inert biomaterial having purity 99.5% Aluminium oxide (Al2O3) and 0.5% Magnesium oxide (MgO), find its wide application in dental implant due to good bio-compatible property with adjacent tissue, better wear and aesthetic characteristics. This paper represents the in-vitro tests conducted to evaluation toxicity by cell culturing on Alumina biomaterial used in the dental implant by both direct contact and extraction method. In the present study in-vitro assessment of tissue bio compatibility was conducted on L929 cell line (mouse fibroblast). In-vitro test, the toxicity of Alumina specimen was done by computing percentage of viability in a cell cultured medium. An MTT system was used to measure the active cell activities with mitochondrial-dehydrogenases, which is an easy method which gives accurate and precision results. The results of biocompatibility in-vitro test by both Direct and Extraction methods confirmed that Alumina exhibits a highest cell growth of 93.05% and resulted with zero grade cytotoxicity. Alumina having good aesthetic characteristics i.e., colour of the implant matches with the tooth colour. Hence Alumina is a best candidate alternate implant material compared to other metal implants.

In this paper, we look at how different nickel concentrations (4, 8, and 12 percent) affect the microstructure, microhardness, and dry sliding wear behaviour of a Cu-Zn-xNi alloy. The alloy was created using a casting technique at 1100°C and a heat treatment method that included solution treatment at 600°C and ageing at 450°C for four hours each. Microstructure studies were performed on the developed alloys using a scanning electron microscope (SEM). To investigate alloy indentation resistance, an ASTM E384 microhardness test was performed. Tribological properties such as friction and wear were investigated using a pin on disc tribometer and a dry sliding wear test according to the ASTM G99 standard. SEM studies revealed α-phase (copper) and solid solution of zinc in cast alloys, while aged alloys revealed a similar structure but with the addition of Cu2NiZn precipitates. The microhardness values improved as the Ni content and ageing increased. The decrease in secondary dendrite arm spacing with increasing Ni content and ageing was attributed to the improvement. The coefficient of friction decreased as the load increased, but increased as the sliding velocity increased. However, as loads and sliding velocities increased, so did the wear rate. For the majority of loads and sliding velocities, the worn surface demonstrated abrasion as the dominant wear mechanism.

Abstract Zirconia Toughened Alumina (ZTA) is an advanced ceramic bio-inert biomaterial comprising of 80% Alumina and 20% Yttria stabilised Zirconia. These bio-inert biomaterial is used in the field of medical applications specifically in total hip joint due to its unique characteristics of minimum interaction with surrounding tissue and good compatibility. This paper presents the Triboligical behaviour or Wear behaviour of ZTA pin and ZTA Plate when subjected to wear test. Ducom Linear Reciprocating Tribometer was used for testing the wear in ZTA Pin and ZTA Plate specimens. The test results confirmed that the average wear rate of ZTA pin and ZTA plate specimen was minimum as 6.2498x10-9 g/Nm. The coefficient of friction of ZTA pin on ZTA plate was found to be 0.333, frictional force was found to be 6.666 N and operating temperature was 37 ± 0.2o C. The above parameters were within the admissible limits as per ASTM standards used for implant material. Hence Zirconia toughened Alumina Bio-inert material is agood candidate implant biomaterial for Total hip joint replacement and other medical applications.

Zirconia is a bioinert ceramic biomaterial. Zirconia having composition of 97% Zirconia oxide and 3% Yttria oxide finds its vital application in the field of dental ceramics as an implant material for having good inert characteristics like minimum interaction with the adjacent tissues and exhibits good aesthetic property. This paper presents the in-vitro tests conducted to evaluation toxicity by cell culturing on zirconia biomaterial used in the dental implant by both direct contact and extraction method. In the present study, in-vitro assessment of tissue biocompatibility was conducted on L929 cell line (mouse fibroblast). In-vitro test, the toxicity of Zirconia specimen was done by computing percentage of viability in a cell-cultured medium. An MTT system was used to measure the active cell activities with mitochondrial dehydrogenases, which is an easy method which gives accurate and precision results. The results of biocompatibility in-vitro test by both Direct and Extraction methods confirmed that Zirconia exhibits the highest cell growth of 93.17% and resulted with zero-grade cytotoxicity. Zirconia having good aesthetic characteristics, i.e. colour of the implant matches with the tooth colour. Hence Zirconia is a candidate implant material than other metal implants.

Commercially available LM4 Aluminum alloy was subjected through Severe Plastic Deformation (SPD) method by Multi-Axial Forging Process (MAF) in ambient temperature. In this process, the material was processed successfully up to 5 Passes and mechanical properties such as tensile strength, compression strength and hardness of the as received and processed samples at ambient temperature were evaluated. The MAF processed sample result showed that the ultimate strength, percentage elongation and compression strength improved by 55 MPa, 3.75% and 162 MPa respectively as compared with the unprocessed sample. Hardness also increased with the increase in the number of passes. In the case of microstructure, grain size reduced from 110 μm to 8 μm after subjecting the sample to MAF. Fractography explains the nature of the fracture from received to processed samples by decreasing the size of the dimple and the type of fracture observed was ductile in nature. Improvement in strength and hardness of processed samples was observed due to the grain refinement and high amount of density dislocation in the material during MAF.

Vessel Plus is an open acccess journal, which publishes articles related to vascular diseases, including acute respiratory distress syndrome, aneurysm, atherosclerosis, hypertension, stroke, peripheral vascular or pulmonary vascular diseases, etc.

In the present investigation, commercially available light metal aluminium LM6 alloy was processed by Multi-axial forging (MAF) at ambient temperature. MAF was carried out to an equivalent strain in 0.83, 1.66 and 2.4 i.e., 6 passes, 12 passes and 18 passes, respectively. The mechanical properties like tensile test, compression test, hardness and microstructural characterization were studied in processed and unprocessed samples. Ultimate tensile strength (UTS) and ductility improved from 137 to 185 MPa and 3 to 6.2% for as-received to processed samples, respectively. After 18 passes of MAF, the compression strength (CS) has improved from 342 to 530 MPa. Hardness increased as the number of forging passes increases as compared to unprocessed samples. Optical microscopy images were used to study microstructure observations, the average grain size is reduced from 60 to 2 mu m for as-received to processed samples, respectively. Strength and hardness increased because of the grain refinement for the processed samples and the introduction of the high amount of dislocation density into the material during the MAF process. Fracture study was conducted by utilizing scanning electron microscopy, dimples on tensile fracture surfaces revealed that ductile mode of fracture.

Abstract: Zirconia is an advanced ceramic material widely used in dental implants because of its good inert characteristics like minimum interaction and good aesthetic properties. The finite element method (FEM) is an effective approach for the analysis of dental implants and dental structures. In the present work, a three-dimensional (3D) model of a molar tooth was generated by CATIA V5 software, and an analysis was carried out by the commercial FEA (Finite Element Analysis) software Ansys 14.5 to evaluate the displacement, strain, stress, fatigue life and factor of safety in the proximal region of the zirconia molar tooth implant under static load conditions of 50, 100, 150, 200, 250 and 300 N. The results show that the displacement, strain and stresses, fatigue life and factor of safety were within the material admissible limits for zirconia. Hence, the study reveals that zirconia can be a candidate biomaterial suitable for dental implants as compared to metal implants.

Atherosclerosis is the most common cause of death in the world, accounting for 48% of all deaths in the world. Atherosclerosis, also known as coronary artery disease occurs when excess cholesterol attaches itself to the walls of blood vessels. Coronary stein implantation is one of the most important procedures to treating coronary artery disease such atherosclerosis. Due to its efficiency, flexibility and simplicity, the use of coronary stents procedures has increased rapidly. In order to have better output of stent implantation, it is needed to study and analyze the biomechanical behavior of this device before manufacturing and put into use. Biomaterials are commonly used for medical application in cardiovascular stent implantation. A biomaterial is a non-viable material used as medical implant, so it is intended to interact with biological system. In this paper, an explicit dynamic analysis is used for analyzing the biomechanical behavior of cardiovascular stein by using finite element analysis tool, ABAQUS 6.10. Results showed that a best suitable biomaterial for cardiovascular stent implants, which exhibits an outstanding biocompatibility and biomechanical characteristics will be aimed at which will be quite useful to the human beings worldwide.

Cardiovascular disease such as atherosclerosis is one of the most common diseases in modern days which may cause pain and heart attack. Stenting is non surgical method to treat the atherosclerosis. Due to its efficiency and simplicity, the use of coronary stents in interventional procedures has rapidly increased and different stents have been introduced in the market. In order to have better output of the stent implantation, it is needed to analyze the mechanical behavior of this device before manufacturing and utilizing. The aim of this work is to investigate the biomechanical behavior of stent such as non linear bending analysis at different loading conditions by using different biomaterials. One of the most effective methods to investigate the biomechanical behavior of the stent is finite element method. A commercially available finite element package ABAQUS6.10 has been used for the analysis.

Coronary stent implantation is one of the most important procedures to treating coronary artery disease such atherosclerosis. Due to its efficiency, flexibility and simplicity, the use of coronary stents procedures has increased rapidly. In order to have better output of stent implantation, it is needed to analyze the biomechanical behavior of this device before manufacturing and utilizing. Finite element method is one of the most effective methods to investigate biomechanical behavior of the stent. The objective of this research work is to investigate expansion characteristics of coronary stent for diverse materials, such as PEEK 450G, Magnesium AZ31 and CobaltChromium L605. The results demonstrate the radial displacement, dogbone ratio, foreshortening, and flexibility of diverse materials.