background and aims: elastomeric chains and niti coil springs are two major traction aids in orthodontic tooth movements. force degradation occurs over time in both groups, with higher percentages in elastic chains. the effects of environmental factors and some mouth rinses on this force decay have been previously studied. no study has been performed to evaluate the effect of current popular mo...

statement of problem: a recent technique (mbt) has been introduced for easy and efficient orthodontic treatment by means of straight wire fixed appliances. although this technique has many advantages, in space closure stage causes up righting problem in upper incisors, which should be adjusted by applying additional torque in anterior region. purpose: the purpose of this clinical trial was to d...

Sliding mechanic has become a popular method for space closure with developments in preadjusted edgewise appliance. Furthermore, various space closing auxiliaries have been developed and evaluated extensively for their clinical efficiency. Their effectiveness enhanced with optimum force magnitude and low-load deflection rate (LDR)/force decay. With the advent of NiTi springs in orthodontics, LD...

Open coil springs are commonly used in orthodontic practice to create space for a palatally or lingually blocked out tooth. However, very often the clinician encounters a situation where the inter-bracket span is very less and the open coil spring is not long enough to open the required space needed for alignment. In such situations, the clinician needs to remove the arch wire and reinserts a l...

This paper demonstrates the feasibility of replacing the metal coil spring with the composite coil spring. Three different types of springs were made using glass fiber, carbon fiber and combination of glass fiber and carbon fiber. The objective of the study is to reduce the weight of the spring. According to the experimental results the spring rate of the carbon fiber spring is 34% more than th...

We experimentally investigate the influence of slit-like confinement on the coil-stretch transition of single DNA molecules in a homogeneous planar elongational electric field. We observe a more gradual coil-stretch transition characterized by two distinct critical strain rates for DNA in confinement, different from the unconfined case where a single critical strain rate exists. We postulate th...