Objectives Dental implant is a revolution in dentistry; some shortages are still a focus of research. This study use long duration of radiofrequency (RF)–magnetron sputtering to coat titanium (Ti) implant with hydroxyapatite (HA) to obtain a uniform, strongly adhered in a few micrometers in thickness. Materials and Methods Two types of substrates, discs and root form cylinders were prepared using a grade 1 commercially pure (CP) Ti rod. A RF–magnetron sputtering device was used to coat specimens with HA. Magnetron sputtering was set at 150 W for 22 hours at 100°C under continuous argon gas flow and substrate rotation at 10 rpm. Coat properties were evaluated via field emission scanning electron microscopy (FESEM), scanning electron microscopy–energy dispersive X-ray (EDX) analysis, atomic force microscopy, and Vickers hardness (VH). Student’s t-test was used. Results All FESEM images showed a homogeneous, continuous, and crack-free HA coat with a rough surface. EDX analysis revealed inclusion of HA particles within the substrate surface in a calcium (Ca)/phosphorus (P) ratio (16.58/11.31) close to that of HA. Elemental and EDX analyses showed Ca, Ti, P, and oxygen within Ti. The FESEM views at a cross-section of the substrate showed an average of 7 µm coat thickness. Moreover, these images revealed a dense, compact, and uniform continuous adhesion between the coat layer and the substrate. Roughness result indicated highly significant difference between uncoated Ti and HA coat (p-value < 0.05). A significant improvement in the VH value was observed when coat hardness was compared with the Ti substrate hardness (p-value < 0.05). Conclusion Prolonged magnetron sputtering successfully coat Ti dental implants with HA in micrometers thickness which is well adhered essentially in excellent osseointegration.
Soil-structure frictional resistance is an important parameter in the design of many foundation systems. The soil-structure interface area is responsible for load transferring from the structure to the surrounding soil. The mobilized shaft resistance of axially loaded, long slender pile embedded in dense, dry sand is experimentally and numerically analyzed when subjected to pullout force. Experimental setup including an instrumented model pile while the finite element method is used as a numerical analysis tool. The hypoplasticity model is used to model the soil adjacent to and surrounding the pile by using ABAQUS FEA (6.17.1). The soil-structure interface behavior depends on many factors, but mainly on the interface soi
... Show MoreGlass Ionomer Cement (GIC) is one of the important dental temporary filing materials. The aim of this study is to evaluate the effect of adding 3, 5 and 7 wt. % of TiO2 microparticles to conventional GIC powder (Riva Self Cure) on mechanical properties and its effect on absorption and solubility processes. TiO2 particles additives improved compressive strength and biaxial flexural strength, where the compressive strength increased with increasing in the added ratio, while the highest value of the biaxial flexural strength was at 3 wt.%. The addition of TiO2 particles improved the surface Vickers microhardness values, with highest value at 5 wt. %. On other hand TiO2 addition im
... Show MoreExperimental results on harmonic distortions in 13.56 MHz RF Argon glow discharge using different grounded electrodes areas and electrodes spacing are presented. The experiment is carried out at four pressure values. RF power values used are between 20 and 90 watts. The results indicate significant increase in distortions at two specific values of the cone angle enclosing the two electrodes within its geometrical volume. The computation of the cone head angle gave the symmetry discharge or asymmetry as well as when the angle is small the condition is near symmetry discharge associated with decrease in the nonlinearity.
Recently, wireless charging based RF harvesting has interfered our lives [1] significantly through the different applications including biomedical, military, IoT, RF energy harvesting, IT-care, and RFID technologies. Wirelessly powered low energy devices become significantly essential for a wide spectrum of sensing applications [1]. Such devices require for low energy resources from sunlight, mechanical vibration, thermal gradients, convection flows or other forms of harvestable energy [2]. One of the emerging power extraction resources based on passive devices is harvesting radio frequency (RF) signals powers [3]–[5]. Such applications need devices that can be organized in very large numbers, so, making separate node battery impractical.
... Show MorePatient satisfaction and dental anxiety considered as an important factors in dental health care and treatment because they greatly affect the patient's cooperation with the dentist and the extent to which follows the guidelines, treatment and preventive instruction. The present study investigates the relationship between patient satisfaction and dental anxiety, as well as their relation to demographic variables such as gender, age, number of visits, and cultural level. The study was applied on a random sample of dental clinics in Baghdad city with total of (200) patient (108 male and 92 female). Two scales were used in this study, patient satisfaction scale PSS (included 9 aspects, constructed by authors) and Iraqi dental anxiety scale
... Show MorePMMA (Poly methyl methacrylate) is considered one of the most commonly used materials in denture base fabrication due to its ideal properties. Although, a major problem with this resin is the frequent fractures due to heavy chewing forces which lead to early crack and fracture in clinical use. The addition of nanoparticles as filler performed in this study to enhance its selected mechanical properties. The Nano-additive effect investigated in normal circumstances and under a different temperature during water exposure. First, tests applied on the prepared samples at room temperature and then after exposure to water bath at (20, 40, 60) C° respectively. SEM, PSD, EDX were utilized for samples evaluation in this study. Flexural
... Show MoreAim: surface modification of titanium using fiber laser 1064 nm to enhance the bond strength to resin cement. Material and Methods: thirty titanium discs of 0.6 cm x 0.3 cm (diameter and thickness respectively) were categorized after preparation into three groups (n=10) as follows: control group with no surface treatment and two test groups were treated with fiber laser after estimation the appropriate parameters in the pilot study which are 81 ns pulse duration, 30,000 Hz frequency, 50 µm spot size and 10,000 mm/s scanning speed and different average power values (10 W and 20 W) depending on the tested group. Titanium discs surface characterization was performed by scanning electron microscope (SEM), a
... Show MoreScientists have delved too much into reality and metaphor, and perhaps a topic of Arabic rhetoric has not received the attention and care of scholars as much as the topic of truth and metaphor. The metaphor opens wide horizons of expression in front of the writer so that he has several means by which he can express the one experience, so his imagination takes off depicting the intelligible as tangible, the seen as audible, and the audible as seen. That image presented by the creative writer.
The first thing to note is that the emergence of metaphor as a rhetorical term was at the hands of the Mu'tazila. Muslims differed about the issue of metaphor in the Holy Qur’an, and the beginning of the dispute was about the verses in which the
Chemical bath deposition was used to synthesize ZnO nanorods (NRs) on glass and fluorine_doped tin oxide (FTO) substrates. X-ray diffraction was performed to examine the crystallinity of ZnO nanorod. Results showed that ZnO NRs had a wurtzite crystal structure. Field emission scanning electron microscopy images showed that glass sample had rod-like structure distribution with (50 nm) diameter and average length of approximately (700 nm), whereas the FTO-coated glass sample had 25 nm diameter and average length of approximately 950 nm. The direct optical transition band gaps of the glass and FTO_coated glass samples were( 4 and 4.43 eV), respectively. The structural and optical properties of the synthesized ZnO p
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