Background: Color stability of glass ionomers (GIs) could be affected by many factors such as pH and consumption of liquid medications like antibiotics. Most common antibiotics used during childhood are amoxicillin suspension (AM.S) and azithromycin suspension (AZ.S) which have acidic and basic pH respectively. Aim: to evaluate and compare the effect of AM.S and AZ.S on color stability of nano resin-modified GI. Methods: Thirty disc of nano resin-modified glass ionomer (2mm height x 4mm diameter) were divided into three groups (n=10 for each) and independently exposed to AM.S, AZ.S, and artificial saliva (A.S.). Color stability was evaluated in triplicate by VITA Easyshade® before and after three immersion protocols, repeated over a three-week duration with two-days intervals. In each protocol, samples were exposed for two minutes, three times daily for AM.S, once daily for AZ.S, and A.S. full day. GI discs rinsed off after each immersion and kept in artificial saliva until next immersion period. Results: One way ANOVA test and Post-hoc analysis of the changes in color space compartments of nano-resin modified GI samples demonstrated just a significant change (p˂0.05) in yellow-blue axis (Δb*) value after immersion in AM.S in comparison with A.S. Total Color change values (ΔE) of nano resin-modified glass ionomer samples also illustrated a significant effect (p˂0.05) between AM.S and A.S. only. The highest (ΔE) value was recorded for samples immersed in AM.S (ΔE =12.5) followed by AZ.S (ΔE=6.5) while the lowest was recorded for A.S. (ΔE=1.1). Conclusion: AM.S (the acidic medication) exhibited a higher staining effect to nano-resin modified GI samples when compared with AZ.S (the basic medication). Several factors such as low pH, more exposure time and coloring material of the immersion media added critical roles in coloring instability.
Background and Aim: The use of food dyes can cause certain diseases, such as anemia and indigestion, along with other disorders, tumors, and even cancer. Therefore, this study aimed to determine the chemical nature and toxicity of some commercial dyes locally used in processed foods compared with standard food dyes. Materials and Methods: Three types of standard and commercial food color additives (Sunset Yellow, Tartrazine, and Carmoisine) were extensively examined. The chemical structures and functional groups of the dyes were evaluated by Fourier-transform infrared (FTIR) spectroscopy. The melting temperatures of the dyes were also determined by chemical thermal analysis. The acute toxicity test to evaluate the standard and commercial
... Show MoreIn this study, we try to deviate from the traditional methods of preserving fish. The research depends on finding alternative modern methods by which fish bodies can be preserved in a better way and for long periods after conducting some laboratory treatments on the specimens to ensure obtaining clean and clear samples suitable for diagnosis and study, in addition to keeping it in a new, lightweight and elegant form that can give three-dimensional shapes to the specimens. The final specimens were of high quality and unbreakable durability with high clarity and transparency and low manufacturing costs. This study is the first of its kind.
This research aims to identify the reality of Sino-Russian relations after 2013, and to study the most important motives and determinants that affected the nature of these relations. The research was based on the criterion of national interest in interpreting and understanding relations between China and Russia, on the basis that national interest is what determines the state of cooperation and dependence, or the state of competition and difference. The research was based on the hypothesis that Sino-Russian relations after 2013 witnessed many factors and variables, some of which represented motives for strengthening relations between the two countries, and others represented obstacles that limit the level of cooperation and interaction betw
... Show MoreAbstract: This research deals with the developing of power and different abilities (military, security, economy, technology and scientific excellence) The research shows that the excellence of the Chinese economy and its development , had a positive reflection on the other powers and abilities , it means it is a base of development in all fields. The development in power and Chinese military abilities had a clear effect on Chinese strategic creed , and that what the research deals with in some details. The research also deals with developing Chinese nuclear abilities. The research doesn't ignore the security eye that indicates to the protection of the state sovereignty, concentrating on the unity and safety Chinese lands. The res
... Show MoreObjective: the aim of this study is to invest age and determine the effect of using (2) packing
technique (conventional and new tension technique) on hardness of (2) types of heat cure acrylic
resin which are (Ivoclar and Qual dental type).
Methodology : this study was intended the using of two types of heat cure acrylic (IVoclar and
Qual dental type) which are used in construction of complete denture which packed in two different
packing technique (conventional and new tension technique) and accomplished by using a total of
(40) specimens in diameter of ( 2mm thickness, 2 cm length and 1 cm width) . This specimens were
sectioned and subdivide into (4) group each (10) specimens for one group , then signed as (A, Al B
Background: The apical seal is the single most important factor in determining the success of surgical endodontics, the aim of this study was to compare the sealing ability of Mineral Trioxide Aggregate in three different cavity designs. Materials and Methods: Thirty extracted human single-rooted teeth were divided into three groups of ten teeth per group, a retrograde cavity preparation was carried out using a low speed handpiece and round bur with parallel walls in the first group, ultrasonic retrotip and unit in the second group and a low speed handpiece with a carbide inverted cone bur with undercuts in the third group, all the cavities were filled with MTA. microleakage was measured by dye penetration technique using methylene blue. Re
... Show MoreAbstract
Nano-crystalline ZSM-5 zeolite was synthesized by hydrothermal method using chelating agent and two gel compositions:Compositionɪ:Al2O3:86SiO2:5.5TPA:12.7Na2O:3.4Trien:3320H2O.Compositionɪɪ:Al2O3:68SiO2:5.4TPA:10Na2O:2.6Trien:2626H2O.Study of hydrothermal reaction factors on characteristics of nano- sized zsm-5 has been carried on ,among them are crystallization temperature, crystallization time and concentration of template ( TPAOH ) solution. Synthesis was accomplished in PTFE lined autoclave ( reactor ) . The product were characterized by X-ray diffraction ( XRD ),Atomic force microsc
... Show MoreABSTRACT
The controversy is currently revolving around industrial additives, including antioxidants, their negative effects on consumer health and the emergence of various and various diseases, which led scientists and researchers to intensify most studies on natural antioxidants and their synthesis from medicinal plants mentioned in ancient medicine and in divine books as potential antioxidants of increasing importance. Therefore, this study was designed to synthesize silver nitrate particles from plant leaf extracts (Figs, Olives, and Moringa) and study their effect on bacterial inhibition of each of the undesirable Coliform bacteria (E-Coli,
... Show MoreThis search aim to measure Hardness for Epoxy resin and for unsaturated Polyester resin as base materials for composite Hybrid and the materials used is Hybrid fiber Carbon-Kevlar. The Hand Lay-up method was used to manufacture plates of Epoxy resin (EP) and unsaturated Polyester EP,UPE backed by Hybrid fiber (Carbon-Kevlar) and with small volume fraction 5,10 and 15 for every there are Layer of fibers (1,2 and 3). The hardness test was count for material EP, UPE resin and there composites and that we notice that the Hardness (HB) decreased with increase of temperatures.
