Background: Maxillary first premolar with wide MOD cavity more susceptible to fracture. The aim of this study was to assess the influence of cavity design for cusp coverage on the fracture resistance of weakened maxillary first premolar restored with CAD/CAM hybrid ceramic versus nanohybide composite. Materials and Methods: Fifty six intact maxillary first premolars of approximately comparable sizes were divided into seven groups eight for each: Group A: Intact teeth (control group); Group B: teeth prepared for MOD inlay; Group C: teeth prepared for MOD onlay covering the lingual cusp; Group D: teeth prepared for MOD covering buccal and lingual cusps ,the previous three groups indirectly restored with nanohybrid composite (3M ESPE Z 250 XT); Group E,F,G prepared with the same design as group B, C, D respectively and restored with CAD/CAM hybrid ceramic (VITA ENAMIC). Results: An axial compression test was used to measure the fracture strength of experimented teeth. The readings were analyzed statistically by t-test, one way ANOVA and LSD, then the mode of fracture had been examined. The results showed that sound teeth in group (A) had more fracture resistance values than all experimental groups and the difference were highly significant with group (B, E, F, G).When the influence of cavity design tested among composite groups it showed highly significant difference between group (B) and (C)and the highest fracture resistance value was for group(C), whereas the influence of cavity design among Enamic groups showed highly significant difference between group (E) and (G) the highest fracture resistance value was for group(E).T-test between similar designs showed non-significant difference between MOD groups and highly difference between other groups. Conclusions: Cusp coverage increased the fracture resistance of composite groups but result in non-restorable fracture, while Enamic total onlay presented promising fracture resistance with favorable mode of fracture. Key words: Fracture resistance, CAD/CAM, hybrid ceramic, VITA ENAMIC, nanohybrid composite, cusp coverage.
Background: Decontamination of gutta percha cones was important factor for success of root canal treatment. The aim of the present in vitro study was to identify and to compare the antimicrobial effect of following disinfection solutions: 0.2% chlorhexidine gluconate, Iodine, tetracycline hydrochloride solution, EDTA & formocresol mixed with zinc oxide eugenol, on E faecalis, E coli and Candida albicans using sensitivity test Materials and Methods: Three types of microorganisms were isolated from infected root canals (E faecalis, E coli and Candida albicans) and cultured on Mueller Hinton agar petri-dishes. Disinfection of gutta percha cones done by immersion in six disinfection solutions (six groups), the groups are: distill water (used a
... Show MoreThis study proposes a hybrid predictive maintenance framework that integrates the Kolmogorov-Arnold Network (KAN) with Short-Time Fourier Transform (STFT) for intelligent fault diagnosis in industrial rotating machinery. The method is designed to address challenges posed by non-linear and non-stationary vibration signals under varying operational conditions. Experimental validation using the FALEX multispecimen test bench demonstrated a high classification accuracy of 97.5%, outperforming traditional models such as SVM, Random Forest, and XGBoost. The approach maintained robust performance across dynamic load scenarios and noisy environments, with precision and recall exceeding 95%. Key contributions include a hardware-accelerated K
... Show MoreLeiomyosarcoma (smooth muscle tumor) is a rare type of a malignant neoplasm of smooth
muscle. It is a resistant cancer, generally not very responsive to chemotherapy, radiationand surgery.The
aim of this study was to evaluate photodynamic therapy (PDT) as a possible basis for treatment using
(650 nm)diode laser with methyleneblue (MB) as a photosensitizer on leiomyosarcoma (LMS)cell line
(L20B) in vitro. The cytotoxic effects of 650nm diode laser 0.052 W/cm2 (power density) at different
exposure time (10, 20, and 30 min) with methylene blue at different concentrations (0.01% ,0.1 % ,1%)
was investigated on LMS cell line (L20 B). The cytotoxic effect of laser was increased with increasing
irradiation time for a certai
The accuracy of the Moment Method for imposing no-slip boundary conditions in the lattice Boltzmann algorithm is investigated numerically using lid-driven cavity flow. Boundary conditions are imposed directly upon the hydrodynamic moments of the lattice Boltzmann equations, rather than the distribution functions, to ensure the constraints are satisfied precisely at grid points. Both single and multiple relaxation time models are applied. The results are in excellent agreement with data obtained from state-of-the-art numerical methods and are shown to converge with second order accuracy in grid spacing.
Fire incidences are classed as catastrophic events, which mean that persons may experience mental distress and trauma. The development of a robotic vehicle specifically designed for fire extinguishing purposes has significant implications, as it not only addresses the issue of fire but also aims to safeguard human lives and minimize the extent of damage caused by indoor fire occurrences. The primary goal of the AFRC is to undergo a metamorphosis, allowing it to operate autonomously as a specialized support vehicle designed exclusively for the task of identifying and extinguishing fires. Researchers have undertaken the tasks of constructing an autonomous vehicle with robotic capabilities, devising a universal algorithm to be employed
... Show MoreEffects of Ozonated Water on Micro Leakage between Enamel and Fissure Sealants Prepared by Different Etching Technique (An in vitro Study), Baraa M Jabar*, Muna S Khalaf
Background: The present study was conducted to evaluate the effects of different bleaching methods on the shear bond strength of orthodontic Sapphire brackets bonded to human premolars teeth using light cured composite resin and to determine the predominant site of bond failure. Materials and Methods: Thirty freshly extracted human premolars were selected and randomly divided into three groups (10 per group). These groups are: control (unbleached) group, hydrogen peroxide group (HP) 37.5% ; which is the in- office bleaching method group, carbamide peroxide group (CP) 16%; which is the at- home bleaching method group. After bleaching process was performed, all the teeth stored in distilled water in a sealed container at room temperature for
... Show MoreThe social networking sites have become one of the most important promotional instruments for their characteristic of facilitation of communication and the creation of public platform for discussion and formation of new points of view. These sites were used in the political marketing process where politicians use Facebook pages to promote their ideologies and spread their programs for the purpose of an influencing public opinion.
This research deals with the way by which political products are the Iraqi parliament. We adopt the methodology for analyzing the contents of these pages during three months starting from September,12 2016 to March 1, 2017 characterized by a lot of changes and events, in particular the beginning of the war o
The aim of the research is to identify the values of the level of muscular strength of the thighs, as well as to identify the significance of the differences between the pre-tests and the post-tests for the first-class football referees in the Iraqi Premier League. The researchers used the one-group experimental approach for its suitability to the nature of the study problem, and the research sample was from first-class referees in the Iraqi Premier League for the sports season (2022/2023), and their number was (15) referees. They took the comprehensive enumeration method, and special tests were conducted on them in the stadium and the private hall at the Ministry of Youth and Sports Center. After analyzing and discussing the result
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