The aim of this study was to compare frictional resistance among conventional, passive and active selfligating brackets using Finite Elements Analysis (FEA). Seventynine (79) slide tests were performed by combining an upper first bicuspid conventional bracket, 0.018" stainless steel wires and 0.010" ligature by means of an INSTRON 3345 load system to obtain average maximum static frictional res...

Understanding the frictional properties of nanostructured surfaces is important because of their increasing application in modern miniaturized devices. In this work, lateral force microscopy was used to study the frictional properties between an AFM nanotip and surfaces bearing well-defined nanodomes comprising densely packed prolate spheroids, of diameters ranging from tens to hundreds of nano...

This paper discusses relationships between the frictional strength of a flowing granular material and quantities including porosity and grain-scale energy dissipation. The goal of the paper is to foster an understanding of frictional strength that will facilitate the development of constitutive laws incorporating important physical processes. This is accomplished in several steps. First, a fric...

A 3-dimensional finite element algorithm for modeling nonlinear frictional contact behaviours between deformable bodies with the node-to-point contact element strategy has been proposed and applied here to investigate stress evolution processes of a nonlinear frictional contact system. The numerical results of a typical intra-plate fault bend model demonstrate the efficiency and usefulness of t...

foundations behavior is affected by soil behavior which can vary from dilative to contractive depending on the stress level, particularly in dense frictional soils. the zero extension lines (zel) method has been generally developed to predict the foundations behavior. knowledge of soil behavior enables the zel method to predict the general and local shear failure modes. in this paper, a relativ...

We develop a theoretical description for mechanically stable frictional packings in terms of the difference between the total number of contacts required for isostatic packings of frictionless disks and the number of contacts in frictional packings, m=Nc0 - Nc. The saddle order m represents the number of unconstrained degrees of freedom that a static packing would possess if friction were remov...

The hydrodynamic frictional resistance to water flow exerted by articular cartilage proteoglycan is shown to be similar to that of proteoglycan isolated from Swarm rat chondrosarcoma, and independent of the state of aggregation of the proteoglycan. Frictional resistance is dependent, however, on the chain segments of the constituent chondroitin-sulphate and keratan-sulphate chains of the proteo...

The aim of this study was to evaluate the frictional force between orthodontic brackets and archwires. The differences in magnitude of the frictional forces generated by ceramic brackets, ceramic brackets with metal reinforced slot, and stainless steel brackets in combination with stainless steel, nickel-titanium, and beta-titanium orthodontic archwires were investigated. Brackets and wire were...

Friction between archwires and labial brackets has received considerable attention; however, information on the frictional behaviour of commercially available lingual brackets is limited. The aim of this study was to investigate the frictional resistance resulting from a combination of lingual orthodontic brackets (7th Generation, STb, Magic, and In-Ovation L) and stainless steel archwires at 0...