Background: Dental implant considers a unique treatment option for the replacement of missing dentition. The new trend of implants is looking for materials which accelerate bone formation in bone implant interface and enhance osseointegration to provide immediate loading directly after placement and decrease the time period which is disturbs patients and uncomfortable. The aim of the study was to evaluate the effect of nano zirconium oxide (ZrO2) and nano hydroxyapatite (Hap) mixture coating of screw shaped commercially pure titanium (cpTi) implants on bond strength at the bone implant interface with torque removal test and histological analysis in comparison with non coated implants. Materials and methods: Forty screws were machined from cpTi rods using a lathe machine. Then 20 screws coated by electrophoretic deposition method by a mixture of nano hydroxyl apatite and nano zirconium oxide, while the other 20 screws remain uncoated. The tibia of 10 adult white New Zealand experimental rabbits was chosen as implantation site, each rabbit tibia received 2 screws, one coated and the other uncoated. Torque removal test was performed to measure the torque required to remove the screw and histological analysis was performed to observe the new bone formation, after 2 and 4 weeks healing intervals. Results: Implant coated with a mixture of nano zirconium oxide and nano hydroxyl apatite showed a significantly higher removal torque values compared to uncoated one. There was more new bone formation with coated implants for both healing periods. Conclusions: Coating by electrophoresis considers a valuable process to coat metallic implants with a ceramic material and to form a uniform composite layer of coating. Osseointegration improved at bone-implant interface associated with the coated implants, which was illustrated by higher bone formation at the two intervals of time 2 weeks and 4 weeks.
This paper proposes feedback linearization control (FBLC) based on function approximation technique (FAT) to regulate the vibrational motion of a smart thin plate considering the effect of axial stretching. The FBLC includes designing a nonlinear control law for the stabilization of the target dynamic system while the closed-loop dynamics are linear with ensured stability. The objective of the FAT is to estimate the cubic nonlinear restoring force vector using the linear parameterization of weighting and orthogonal basis function matrices. Orthogonal Chebyshev polynomials are used as strong approximators for adaptive schemes. The proposed control architecture is applied to a thin plate with a large deflection that stimulates the axial loadi
... Show MoreWater quality sensors have recently received a lot of attention due to their impact on human health. Due to their distinct features, environmental sensors are based on carbon quantum dots (CQDs). In this study, CQDs were prepared using the electro-chemical method, where the structural and optical properties were studied. These quantum dots were used in the environmental sensor application after mixing them with three different materials: CQDs, Alq3 polymer and CQDs and Alq3 solutions using two different methods: drop casting and spin coating, and depositing them on silicon. The sensitivity of the water pollutants was studied for each case of the prepared samples after measuring the change in resistance of the samples at a temperature of
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The research aims to determine the impact of the strategy performance evaluation and of the Standards (leadership, people, knowledge, processes, financial) in the achievement of organizational effectiveness in accordance with the dimensions (planning and setting goals, Exploitation of the Environment, achieve the goals, the ability to adapt, information management and communications) and the relationship between them, the problem of the research in the growing interest in the process of performance evaluation for organizations, the erroneous belief that the performance evaluation activity is useful, and the fact that performance evaluation process is one of the main tasks of the work of the Office of the Inspecto
... Show MoreBackground: Poly (methyl methacrylate) has several disadvantages (poor mechanical properties) like impact and transverse strength. In order to overcome these disadvantages, several methods were used to strengthen the acrylic resin by using different fibers or fillers. This study was conducted to evaluate the effect of Plasma treatment of the fiber on mechanical properties Poly (methyl methacrylate) denture base material. Materials and methods: Specimens were prepared from poly methyl metha acrylic (PMMA) divided according to present of fiber into 4 groups (first group without fiber as control group, second group with Plasma treated polyester fibers, third group with Plasma treated polyamide fibers and fourth group Plasma treated combination
... Show MoreIn the present study, the effects of brake pad particles of lung and liver histological sections were evaluated for (60) adult male mice. The animals were divided into three groups ( A,B,C) according to the periods of exposure (4, 8, and 12) weeks respectively exposed to brake pad particles in addition to the control groups (F) exposed to fresh air only. A special inhalation chamber designed locally has been used to expose the animals. The exposure to brake pad particles was (2.228) µg/m³ for 30 min/day, 5 days/week for (4,8and12) weeks respectively.
The examination in group (A) of the histological sections of the lung showed the thickness of interalveolar septa. Also, a congestion of alveolar capillary was marked indicat
... Show MoreThe aim of this study to investigate the tongue morphology and histology in house gecko Hemidactylus flaviviridis using light and scanning electron –microscopy (SEM ) technique.The morphology result revealed the presence of three parts : apex , body and lingual root .The light microscopy result showed that the tongue is covered with mucous membrane composed of non keratinized stratified squamous epithelium based on lamina propria which contain bundles of striated muscles its fibers in different directions including connective tissue , blood vessels and nerves. The lingual mucosa of the dorsal surface is covered with different pattern of lingual papillae which are widely distributed all over the dorsal surface except the apex. Noticed on t
... Show MoreBackground: Blastocystis spp. distributes world widely and the genus Blastocystis include many subtypes that are isolated from human intestinal tract. It is considered the most common parasite detected in human being.
Objectives: To evaluate the incidence of Blastocystis spp. among leukemic children, to find out its association with the presence of symptoms (diarrhea and abdominal pain), and to assess the efficacy of different staining methods in detection of Blastocystis spp.
Type of the study: cross-sectional study.
Method: 103 children were enrolled in this study, 53 leukemic patients and 50 healthy con
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