Background: The aims of this study were to evaluate the effect of implant site preparation in low-density bone using osseodensification method in terms of implant stability changes during the osseous healing period and peri-implant bone density using CBCT. Material and methods: This prospective observational clinical study included 24 patients who received 46 dental implants that were installed in low-density bone using the osseodensification method. CBCT was used to measure the bone density pre- and postoperatively and implant stability was measured using Periotest® immediately after implant insertion and then after 6 weeks and 12 weeks postoperatively. The data were analyzed using paired t-test and the probability value <0.05 was considered statistically significant. Results: Of the 46 implants, 43 were osseointegrated making the early survival of the implants 93.5%. There was a significant increase in bone density postoperatively; 337.6 ±182.9 compared to 265.3 ±173.9 Hounsfield units preoperatively. The primary implant stability was -2.7 ± 2.13 Periotest values (PTV), at the 6th week it decreased significantly (p<0.0001) to become 0.7 (± 4) PTV, and at the 12th week (secondary stability) it increased significantly (p<0.0001) to become -2.1 (± 2.8) PTV. The difference between primary and secondary stability was statistically non-significant (p=0.0814). Conclusions: Osseodensification resulted in high primary stability and increased peri-implant bone density but it did not prevent the implant stability drop during the first 6 weeks after insertion of implants. Key words:Osseodensification, implant stability, low-density bone.
This paper presents a vibration suppression control design of cantilever beam using two piezoelectric patches. One patch was used as an actuator element, while the other was used as a sensor. The controller design was designed via the balance realization reduction method to elect the reduced order model that is most controllable and observable. the sliding mode observer was designed to estimate six states from the reduced order model but three states are only used in the control law. Estimating a number of states larger than that used is in order to increase the estimation accuracy. Moreover, the state estimation error is proved bounded. An optimal LQR controller is designed then using the estimated states with the slid
... Show Morelarization modulation plays an important role in polarization encoding in quantum key distribution. By using polarization modulation, quantum key distribution systems become more compact and more vulnerable as one laser source is used instead of using multiple laser sources that may cause side-channel attacks. Metasurfaces with their exceptional optical properties have led to the development of versatile ultrathin optical devices. They are made up of planar arrays of resonant or nearly resonant subwavelength pieces and provide complete control over reflected and transmitted electromagnetic waves opening several possibilities for the development of innovative optical components. In this work, the Si nanowire metasurface
... Show MoreAccurate calculation of transient overvoltages and dielectric stresses from fast-front excitations is required to obtain an optimal dielectric design of power components subjected to these conditions, which are commonly due to switching and lightning, as well as utilization of power-electronic devices. Toroidal transformers are generally used at the low voltage level. However, recent investigations and developments have explored their use at the medium voltage level. This paper analyzes the model-based improvement of the insulation design of medium voltage toroidal transformers. Lumped and distributed parameter models are used and compared to predict the transient response and dielectric stress along the transformer winding. The parameters
... Show MoreThe monthly time series of the Total Suspended Solids (TSS) concentrations in Euphrates River at Nasria was analyzed as a time series. The data used for the analysis was the monthly series during (1977-2000).
The series was tested for nonhomogenity and found to be nonhomogeneous. A significant positive jump was observed after 1988. This nonhomogenity was removed using a method suggested by Yevichevich (7). The homogeneous series was then normalized using Box and Cox (2) transformation. The periodic component of the series was fitted using harmonic analyses, and removed from the series to obtain the dependent stochastic component. This component was then modeled using first order autoregressive model (Markovian chain). The above a
... Show MoreAn experimental study was carried out to improve the surface roughness quality of the stainless steel 420 using magnetic abrasive finishing method (MAF). Four independent operation parameters were studied (working gap, coil current, feed rate, and table stroke), and their effects on the MAF process were introduced. A rotating coil electromagnet was designed and implemented to use with plane surfaces. The magnetic abrasive powder used was formed from 33%Fe and 67% Quartz of (250µm mesh size). The lubricant type SAE 20W was used as a binder for the powder contents. Taguchi method was used for designing the experiments and the optimal values of the selected parameters were found. An empirical equation representing the r
... Show MoreShabak is one of minority related to Kurdish nation , speaking Bajalan variety especially Goran Dialect.
This study is a historic and diactological study about Kurdish Bajalan variety.The study is composed an introduction and tw0 chapters. The first chapter talks about Bajalan variety , and it has two axes . In the first axe , I talk about the geography of Bajalan variety and in the second axes the map of goran dialect . The second chapter is about Shabak variety and it is constituted of three axes : The first section is about Shabak variety , in the second section is allocated to the domicile of Shabak variety and in the third section , talks about the saint of shabak and in the end the
... Show MoreObjectives: The aim of this study to assess instructional labor support behaviors among laboring
women in teaching hospitals in Hilla city.
Methodology: A descriptive analytic study was concluded to select a sample purposely of one hundred
multipara laboring women in maternity hospital in Hilla city and data was collected through
questionnaire form during February (1
st to March 30th) 2014. A descriptive statistical method was used
to analyze the data.
Results: The result showed that the highest percentage of study sample was at age (20-24) years, most
of them was house wife, more than third graduate from primary school, and more than half of them
lived in rural area, (86%) of study sample delivered normal deli
In This study a comparison between Proteus mirabilis DNA and Candida albicans DNA in Arthritis. Fourteen Proteus isolates (11.6%) were collected from 120 specimens collected from midstream urine of patients of both sex and different ages attending different hospitals in Baghdad. Antibiotic sensitivity assay showed that All Proteus mirabilis recovered from UTI developed multidrug resistance and variable degree of resistance. Histopathological changes in model treated with Proteus mirabilis DNA revealed congestion, inflammatory cells infiltration, oedema, hemorrhagic exudates as well as necrotic cells. Furthermore, articular joints damage has been noticed with articular tissue in ligament and lining epithelium. In addition, an aggregation
... Show MoreHumans are exposed to nuclear radiations every day, and these radiations are both natural and artificial. When the body tissues are exposed to nuclear radiation, free radicals are formed, which are responsible for cancer development. In this research, silver nanoparticles were synthesized by electrical explosion wire method. Nanoparticles were added to deionized water that contained free radicals before and after exposure to gamma rays. The obtained results indicate that the silver nanoparticles have antioxidant potential through possessing free radical scavenging activity, as they can donate electron to free radicals and become neutralize. Then, these nanoparticles were injected to mice before and after their irradiation with gamma ray.
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