In this paper, an active vibration control of the translating steel strip in the zinc galvanizing line is investigated. The unwanted vibrations of the strip deteriorate the uniformity of the deposited mass on the surfaces of the steel strip and the consumption of zinc. The translating steel strip is modelled as a moving belt equation by using Hamilton’s principle for the systems with changing m...

Background and Aim: Cleaning and shaping is one of the important steps in endodontic treatment, which has an important role in root canal treatment outcome. This study evaluated the rate of file fracture and file deformation in Neolix rotary system and K-files in shaping of the mesiobuccal canal of maxillary first molars with moderate curvature.    Materials and Methods: In this ex vivo exp...

The objective of the study was to evaluate the bacteria extruded apically during root canal preparation using hand and two rotary instrumentation techniques. The method include eighty freshly extracted mandibular premolars were mounted in bacteria collection apparatus. Root canals were contaminated with the pure culture of Enterococcus faecalis (ATCC 29212) and dried at 37 0 c for 24 hour. Then...

INTRODUCTION The aim of this in vitro study was to compare the effect of hand and rotary instruments on fracture strength of tooth roots. MATERIALS AND METHODS Thirty two teeth were randomly divided into two experimental groups of 15 each and one negative control group with two samples. In group 1, step-back technique with conventional stainless steel K-files was used, and in group 2, instrum...

A new type of rotary motor by inchworm motion using two belts is developed. A rotor is wrapped by two opposite belts which are connected to piezoelectric actuators. A serial lever structure with flexure hinges is used to connect a belt and piezoelectric actuators. The lever structure amplifies micro displacement of a piezoelectric actuator. A rotational motion with the step size of 2.36 mrad is...

As compared with continuous rotary systems, reciprocating motion is believed to increase the fatigue resistance of NiTi instruments. We compared the cyclic fatigue and torsional resistance of reciprocating single-file systems and continuous rotary instrumentation systems in simulated root canals. Eighty instruments from the ProTaper Universal, WaveOne, MTwo, and Reciproc systems (n = 20) were s...

Root canal therapy might be required for primary teeth displaying signs of pulpal inflammation or necrosis. Cleaning and shaping followed by obturation of the canal space with a resorbable paste have been widely performed with remarkable clinical success. However, lengthy endodontic procedures might be contraindicated when treating certain pediatric patients. The aim of this study was to compar...

OBJECTIVES The purpose of this study was to compare in-vitro the amount of debris extruded apically from extracted teeth, using K3, Protaper rotary instruments and manual step-back technique. METHODS Forty five human single-rooted mandibular premolar teeth were randomly divided into 3 groups. The teeth in 3 groups were instrumented until reaching the working length with K3, Protaper rotary in...

The rotary vacuum filter is very basic in design, application and operation. It is also an extremely effective solid/liquid separation device due to its unique methods of handling (discharging) formed cake solids, relatively low operating labor requirements and its ability to filter continuous or batch process flows. The rudiments of a rotary vacuum filter installation include (Figure 1): (1) t...

Abstract The radial infeed rotary swaging is widely used as a diameter reduction forming process of axisymmetric workpieces, improving the mechanical properties with excellent near net shape forming. In present study, experiments different parameter setups were performed on steel tubes and bars under material states several resulting property modifications investigated such stress-strain curve,...