Objectives: To assess the performance of a novel resin-modified glass-ionomer cement (pRMGIC) bonded to various tooth tissues after two-time intervals. Methods: 192 sound human molars were randomly assigned to 3 groups (n = 64): sound enamel, demineralised enamel, sound dentine. Sixty-four teeth with natural carious lesions including caries-affected dentine (CAD) were selected. All substrates were prepared, conditioned and restored with pRMGIC (30% ethylene glycol methacrylate phosphate (EGMP, experimental), Fuji II LC (control), Fuji IX, and Filtek™ Supreme with Scotchbond ™ Universal Adhesive. Shear bond strength (SBS) was determined after 24 h and three months storage in SBF at 37C. The debonded surfaces were examined using stereomicroscopy and scanning electron microscopy (SEM). Multivariate Analysis of Variance (MANOVA), Bonferroni post hoc tests (alpha=0.05) and independent T-tests were used for multifactorial data analysis. Results: The hydrophilicity and functionality of EGMP enhanced the bond strength of the pRMGIC to different substrates after 24 h and 3 months as compared to F2LC (p<0.05). Adhesive failures were found to decrease with pRMGIC and integration into exposed enamel prisms and dentine tubules was observed with SEM. Ageing enhanced bond strength of pRMGIC to all substrates but was statistically significantly only in sound dentine. The SBS of pRMGIC was higher with sound vs. demineralised enamel at both time periods (p<0.001), while it was higher to CAD initially and to sound dentine post-storage (p = 0.004). Conclusions: pRMGIC exhibited enhanced bonding performance to various tooth tissues with an ability to seal exposed enamel prisms and dentine tubules. Clinical significance: pRMGIC is a promising material exhibiting long-lasting bonded-tooth interfaces, for its use in minimally invasive reparative techniques
The present work covers the Face-Hobbing method for generation and simulation of meshing of Face hobbed hypoid gear drive. In this work the generation process of hobbed hypoid gear has been achieved by determination of the generation function of blade cutter. The teeth surfaces have been drawn depending on the simulation of the cutting process and the head cutter motion. Tooth contact analysis (TCA) of such gear drive is presented to evaluate analytically the transmission error function for concave and convex tooth side due to misalignment errors. TCA results show that the gear is very sensitive to misalignment errors and
the increasing of the gear teeth number decrease the transmission error for both concave and convex tooth sides a
PMMA films of different thickness (0.006, 0.0105, 0.0206, 0.0385 and 0.056cm) were synthesized by casting process. The temperature and frequency dependence of dielectric constant and AC electrical conductivity measurements at various frequencies (10kHz-10MHz) and temperatures (293-373K) were carried out. Few anomalies in dielectric studies were observed near 313 and 373 K respectively. These points were related to glass transitions temperature. The variation of activation energy and conduction behavior was studied .From the AC conduction studies, it is confirmed that the mechanism responsible for the conduction process is hopping of carriers. The variations of the dielectric constant and loss as function of frequency at different tempera
... Show MoreAs a result of the increase in wireless applications, this led to a spectrum problem, which was often a significant restriction. However, a wide bandwidth (more than two-thirds of the available) remains wasted due to inappropriate usage. As a consequence, the quality of the service of the system was impacted. This problem was resolved by using cognitive radio that provides opportunistic sharing or utilization of the spectrum. This paper analyzes the performance of the cognitive radio spectrum sensing algorithm for the energy detector, which implemented by using a MATLAB Mfile version (2018b). The signal to noise ratio SNR vs. Pd probability of detection for OFDM and SNR vs. BER with CP cyclic prefix with energy dete
... Show MoreBuckling analysis of composite laminates for critical thermal (uniform and linear) and mechanical loads is reported here. The objective of this work is to carry out theoretical investigation of buckling analysis of composite plates under thermomechanical loads, and experimental investigation under mechanical loads. The analytical investigation involved certain mathematical preliminaries, a study of equations of orthotropic elasticity for classical laminated plate theory (CLPT), higher order shear deformation plate theory (HSDT) , and numerical analysis (Finite element method), then the equation of motion are derived and solved using Navier method and Levy method for symmetric and anti-symmetric cross-ply and angle-ply laminated plates t
... Show MoreIn this paper, I highlight the bishops mentioned in the Bible in its sections
(The Old and New Testaments) where these books still retain the remaining remnant of the Bible
Issuing the prophets who preceded the mission of the Prophet Muhammad (peace and blessings of Allaah be upon him) and they must pray
And peace, as those bishops were mentioned in the Book of Formation through the recitation of the psalms
To Habakkuk, Malakhi, and Hajji.
As well as in the New Testament, which we see clearly in the four Angels: Matthew, Luke,
Disco, John.
Then the male lamented what was said of those bishops by expressing the eternal heavenly book (the Qur'an)
Al - Karim) as he focuses on this subject from multiple angles and exp
Abstract:
The internal audit is considered the safety valve for senior management in all institutions. It aims to protect property, and raise the efficiency and effectiveness of the administrative performance, by following up on compliance with laws and instructions and the application of regulations in a way that increases the administrative performance of the department. The internal audit is possible to determine Weaknesses or imbalances in the administrative performance. To achieve this goal, an analytical descriptive methodology was adopted. The Baghdad Health Department / Al-Rosana was considered as society for this s
... Show MoreObjectives: Successful endodontic treatment outcome requires effective shaping and cleaning of root canals. This study aims to evaluate the smear layer removal after continuous chelation (CC) ) NaOCL\HEDP( and sequential chelation (SC) )NaOCL\EDTA( and their influence on the push-out bond strength (POBS) of Bio-C sealer. Materials and Methods: Palatal roots of the maxillary first molar (n=72) were divided into four groups (n=18) as follows: 3% NaOCL, SC: 3% NaOCL followed by 17% EDTA, CC: 3% NaOCL \9% HEDP and Distilled water. Thirty-two roots (n=8/group) were split longitudinally for smear layer evaluation using SEM. Forty roots were obturated with Guttapercha and Bio-C sealer using a single cone technique. Thre
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