The aim of this study was to evaluate the effect of RaCe, FlexMaster and ProFile rotary instruments on smear layer formation by scanning electron microscopy. Eighty-four caries-free freshly extracted human single-rooted teeth were selected and divided into three groups, each containing 28 teeth. The teeth were instrumented with rotary instruments sequentially: Group A: ProFile Rotary Instrument...

Aim The aim of this study is to compare curved root canal preparation between reciprocal rotary files and rotational rotary files in extracted teeth using cone-beam computed tomography (CBCT). The independent variable was the file type (reciprocal vs. rotary), and the primary outcome variable was the centering ratio of distance change after canal preparation. Secondary outcomes were canal trans...

DNA has been used to construct a wide variety of nanoscale molecular devices. Inspiration for such synthetic molecular machines is frequently drawn from protein motors, which are naturally occurring and ubiquitous. However, despite the fact that rotary motors such as ATP synthase and the bacterial flagellar motor play extremely important roles in nature, very few rotary devices have been constr...

Four-month-old infants were allowed to manipulate, without vision, two rings attached to a bar that permitted each ring to undergo rotary motion against a fixed surface. In different conditions, the relative motions of the rings were rigid, independent, or opposite, and they circled either the same fixed point outside the zone of manipulation or spatially separated points. Infants' perception o...

ultrasonic machining (usm) is a mechanical material removal process used to erode holes and cavities in hard or brittle work pieces by using shaped tools, high-frequency and an abrasive slurry. this paper addresses the concept and development of an expert system (es) for hard and brittle material, such as glass, quartz, diamond, carbides, semi conducting materials, ceramic and graphite which ca...

Hair transplantation involving patients with tightly curled Afro-textured hair using follicular unit extraction (FUE) employing conventional rotary punches frequently leads to unacceptably high transection rates. These patients are unsuitable candidates for FUE hair transplantation. Transection rates were observed during FUE in a case series of 18 patients with tightly curled Afro-textured hair...

OBJECTIVES The present study was conducted to compare the cleaning efficacy (debris and smear layer removal) of hand and two NiTi rotary instrumentation systems (K3 and ProTaper). MATERIALS AND METHODS Sixty single rooted human maxillary anterior teeth decoronated at the cementoenamel junction were used. All the specimens were divided into four groups of 15 teeth each, group I--ProTaper rotar...