Objective. Glass-ionomer and resin-modified glass-ionomer cements are versatile materials with the ability to form a direct bond with tooth tissues. The aim of this study was to formulate a novel class of dental bio-interactive restorative material (pRMGIC) based on resin-modified glass-ionomer cements via the inclusion of an organophosphorus monomer, ethylene glycol methacrylate phosphate, with a potential to improve the mechanical properties and also function as a reparative restorative material. Methods. pRMGIC was formulated with modification of the resin phase by forming mixes of ethylene glycol methacrylate phosphate (EGMP; 0–40%wt) and 2-hydroxyethyl methacrylate monomer into the liquid phase of a RMGIC (Fuji II LC, GC Corp.). The physical properties of the cements were determined including setting characteristics, compressive strength and modulus (CS &CM), microhardness (MH) and biaxialflexural strength (BFS). Fluid uptake and fluoride release were assessed up to 60 days storage. Adhesion to sound dentine was measured using micro-tensile bond strength and surface integrity was analysed using SEM coupled with EDX. Statistical analysis was performed using ANOVA and Bonferroni post-hoc tests. Results. The pRMGIC cements exhibited an increase in working time with increasing EGMP concentration however were within the limits of standard clinical requirements. Although the compressive strength of pRMGIC cements were comparable to control cements in the early stages of maturation, the higher EGMP-containing cements (EGMP30 and 40) exhibited significantly greater values (p < 0.05) after 4 weeks storage (141.0 ± 9 and 140.4 ± 8 MPa, respectively), in comparison to EGMP0 (128.8 ± 7 MPa). A dramatic two fold increase in biaxial flexural strength (p < 0.001) was observed for the pRMGIC’s. Furthermore, the ability to decalcify tooth apatite resulted in enhanced interfacial adhesion due to chelation with calcium ions of tooth apatite. The inclusion of EGMP encouraged formation of reinforcing complexes within the RMGIC, thus improving physical properties, decreasing solubility and lower fluoride release. A dense microstructure was observed with increasing EGMP content. Significance. A novel universal bio-interactive adhesive repair material will enable clinicians to offer more effective repair of the tooth-restoration complex, thus future treatments will benefit both patient and a severely constrained healthcare budget.
The extracting of personal sprite from the whole image faced many problems in separating the sprite edge from the unneeded parts, some image software try to automate this process, but usually they couldn't find the edge or have false result. In this paper, the authors have made an enhancement on the use of Canny edge detection to locate the sprite from the whole image by adding some enhancement steps by using MATLAB. Moreover, remove all the non-relevant information from the image by selecting only the sprite and place it in a transparent background. The results of comparing the Canny edge detection with the proposed method shows improvement in the edge detection.
This paper presents a hybrid genetic algorithm (hGA) for optimizing the maximum likelihood function ln(L(phi(1),theta(1)))of the mixed model ARMA(1,1). The presented hybrid genetic algorithm (hGA) couples two processes: the canonical genetic algorithm (cGA) composed of three main steps: selection, local recombination and mutation, with the local search algorithm represent by steepest descent algorithm (sDA) which is defined by three basic parameters: frequency, probability, and number of local search iterations. The experimental design is based on simulating the cGA, hGA, and sDA algorithms with different values of model parameters, and sample size(n). The study contains comparison among these algorithms depending on MSE value. One can conc
... Show MoreDental caries is a common chronic disease affecting tooth of many subjects at different ages due to biofilm-mediated oral bacterial infection.
Background: Undergraduate dental students are more susceptible to situations of stress that affected quality of sleep, such profiles of stress may result in sleep bruxism and/or awake bruxism, parafunctions that can affect oral and general health. The aim of the study was to evaluate the association of sleep bruxism, awake bruxism and sleep quality among dental students. Materials and methods: A cross-sectional study was performed including 260 Iraqi dental students from university of Baghdad aged from 20to25years old. Students enrolled in the third and fifth class participated in the study. The Pittsburgh Sleep Questionnaire Index (PSQI) was used for data collection. The PSQI was distributed during lecture classes. Sleep bruxism and awake
... Show MoreThe research topic was chosen because of the importance of communication in organizations in general and the marketing process in particular. Without communication, the organization can not live and continue ,The problem of study diagnosis the reduction in sales in the company of plant oils in some its classes and weakness in differentiation and its reputation at market in spit if having good products with standardized features And lack of customer communication channels, also the company does not have any whole view about the concept of marketing communication, Therefore, This sudy aimed ro define to know the type of relationship between the extent of the impact of the integrated marketing
... Show MoreThe reservoir characterization and rock typing is a significant tool in performance and prediction of the reservoirs and understanding reservoir architecture, the present work is reservoir characterization and quality Analysis of Carbonate Rock-Types, Yamama carbonate reservoir within southern Iraq has been chosen. Yamama Formation has been affected by different digenesis processes, which impacted on the reservoir quality, where high positively affected were: dissolution and fractures have been improving porosity and permeability, and destructive affected were cementation and compaction, destroyed the porosity and permeability. Depositional reservoir rock types characterization has been identified de