Background: Curve of Spee (CS) is an anteroposterior anatomical curve established by the occlusal alignment of the teeth viewed in the sagittal plane. This occlusal curvature has clinical importance in orthodontics and other fields of dentistry. This study aimed to evaluate the relationship between the CS and dentofacial morphology of different skeletal patterns in both genders. Materials and Methods: Eighty six Iraqi Arab subjects (44females,42 males ) their age ranged from 17 -30 years, classified into: Skeletal I with normal occlusion(15 females and 15 males), skeletal II with CI II div 1 malocclusion (15 females and 15 males) and skeletal III with CI III malocclusion (14 females and 12 males). Forty one variables measured using direct dental cast measurements , dental cast photographs and cephalometric radiographs with the aid of AutoCAD program version 15 (2006). Results: No significant differences in the CS depth between males and females or between right and left sides in both arches of different skeletal patterns. No significant differences in the maxillary CS among the 3 skeletal patterns, the mandibular CS in CI II div 1 malocclusion was larger than normal occlusion and CI III malocclusion. Maxillary CS significantly correlated to arch length, inter canine distance and inter second premolar distance in normal occlusion and overbite in Cl III malocclusion. Mandibular CS significantly correlated with overbite and overjet in Cl II div 1 and Cl III malocclusions. Conclusions: CS was not influence by sides and gender in both arches of different skeletal patterns. CS was concave in the mandibular arch with the maximum concavity at the mesio-buccal cusp tip of the mandibular first molar and convex in the maxillary arch with the maximum convexity at the buccal cusp tip of the maxillary second premolar, in different skeletal patterns. Key words: Curve of Spee, arch length, overbite, overjet, dentofacial morphology.
One of the most important problems in tablet process is to control the flow of the catalyst through the hopper; Controlling the flow can be done either by changing the size of particles or added the different lubricant (stearic acid, starch, graphite) or blending of different lubricants. The study showed that we can control (increase or decrease) on the flow of the catalyst through the hopper by blending different lubricants for the constant percentage. The flow increasing when particles size (0.6 mm) and then decrease with or without lubricants, no effect on flow when particles size lower than (0.2 mm) with use that lubricants, and good flow on (0.4 mm) when use stearic acid and starch.
RMK Al-Zaidi, MM Ahmed
It highlights the importance of construction projects because of its significant role in the development of society, including the buildings FEDE projects to their importance to raise the level of education through the conclusion of the special to implementation and the establishment of schools of contracts at the country level, which requires the completion of the project at less time and within the cost specified and the best quality and may highlight the importance of time on all the elements of what has an important role in setting up the project for various reasons may be the need for the use of schools as soon as possible, but the reality showed exceeded the completion of those schools could be up to 6 years and there are some cont
... Show MoreThe current study was conducted in the environment of the Martyr Monument Lake in the city center of Baghdad during 2019 to monitor the impact of climatic conditions such as drought, water shortage, high temperatures in the environment of the city and the lack of water flow during the years 2015 to 2018 and their effects on some of the physical and chemical factors of water and the dynamics of the phytoplankton community in the lake environment. Heterogeneity of some studied environmental factors, including air and water temperature, permeability, water depth, pH, DO, BOD5, nutrients, nitrate, NO3, and phosphates were found. The results showed the effect of climate change and the pres
Background: The objective of this in vitro study was to evaluate the vertical marginal fit of crowns fabricated with ZrO2 CAD/CAM, before and after porcelain firing cycles and after glaze cycles. Materials and Methods: An acrylic resin model of a left maxillary first molar was prepared and duplicated to have Nickel-Chromium master die. Ten die stone dies were sent to the CAD/CAM (Amann Girrbach) for crowns fabrication. Marginal gaps along vertical planes were measured at four indentations at the (mid mesial, mid distal, mid buccal, mid palatal) before (Time 0) and after porcelain firing cycles (Time 1) and after glaze cycles (Time 2) using a light microscope at a magnification of ×100. One way ANOVA LSD tests were performed to determine wh
... Show MoreIn this paper, Pentacene based-organic field effect transistors (OFETs) by using different layers (monolayer, bilayer and trilayer) for three different gate insulators (ZrO2, PVA and CYEPL) were studied its current–voltage (I-V) characteristics by using the gradual-channel approximation model. The device exhibits a typical output curve of a field-effect transistor (FET). Source-drain voltage (Vds) was also investigated to study the effects of gate dielectric on electrical performance for OFET. The effect of capacitance semiconductor in performance OFETs was considered. The values of current and transconductance which calculated using MATLAB simulation. It exhibited a value of current increase with increasing source-drain voltage.
In this paper, Pentacene based-organic field effect transistors (OFETs) by using different layers (monolayer, bilayer and trilayer) for three different gate insulators (ZrO2, PVA and CYEPL) were studied its current–voltage (I-V) characteristics by using the gradual-channel approximation model. The device exhibits a typical output curve of a field-effect transistor (FET). Source-drain voltage (Vds) was also investigated to study the effects of gate dielectric on electrical performance for OFET. The effect of capacitancesemiconductor in performance OFETs was considered. The values of current and transconductance which calculated using MATLAB simulation. It exhibited a value of current increase with increasing source-drain voltage.