statement of the problem : tooth restorations are exposed to stresses which produce marginal gaps resulting in microleakage. purpose in this study, microleakage of light-cured glass-ionomer and compomer class v restorations was evaluted and compared under cyclic loading materials and methods in this exprimental study, class v cavities were prepared on the buccal surfaces of maxillary premolars ...

this article considers the seismic behavior of beam-to-column joints in steel frames for different bolt arrangements by using of finite element modeling. as the most important beam-to-column joint type, the beam-to-column joints with end-plate is chosen for the analysis. four different specimens have been analyzed. these models had some differences such as bolt arrangement and the presence or a...

the aim of this study was to evaluate the effect of cyclic loading on the bond strength of quartz fiber posts to root canal dentin after different surface treatments of different regions of root canal dentin.forty-eight single-rooted human teeth were selected. post spaces were prepared and then the teeth were divided into four groups: g1: no treatment (control); g2: irrigation with a chemical s...

objective: optimal dentin bonding is not always obtained in clinical practice due to func-tional forces. these forces may provide stresses throughout the tooth and restorative sys-tem, which in turn may affect the adhesive bond. this experimental study evaluated the effect of load cycling on bond strength of self-etch systems. materials and methods: one third of the coronal portions of 48 intac...

background: microleakage is one of the challenging concerns in direct fi lling restorations. understanding of its related factors is important in clinical practice. the aim of this study was scanning electron microscopy (sem) evaluation of marginal integrity in three types of tooth-colored restorative materials in class v cavity preparations and the effect of load cycling and polishing time on ...

Cyclists seek to maximize performance during competition, and gross efficiency is an important factor affecting performance. Gross efficiency is itself affected by pedal rate. Thus, it is important to understand factors that affect freely chosen pedal rate. Crank inertial load varies greatly during road cycling based on the selected gear ratio. Nevertheless, the possible influence of crank iner...

Received: 9 June 2011 Accepted: 29 August 2011 Abstract Background and Aim: Microleakage is an important problem with direct restorations and familiarity with its contributing factors is of utmost importance. The aim of this study was scanning electron microscopic evaluation of marginal integrity in three types of class V tooth-colored restorations and the effect of load cycling on their microl...