OBJECTIVE Retreatment of a root canal in the case of infection requires complete removal of previous filling material. This study evaluated the efficacy of 3 techniques in removing laterally compacted Resilon/Epiphany and gutta-percha/AH Plus from straight and curved canals during retreatment. MATERIALS AND METHODS Extracted human teeth (90 maxillary anterior teeth with single,straight root c...

This thesis identifies operational uncertainty as a significant problem affecting reliable robot performance in real environments. Operational uncertainty represents ambiguity in a robot’s self-perceived state during the execution of a task. This ambiguity is introduced into a robotic system through events such as unanticipated environmental disturbances, failing hardware and software built upo...

Sources and sinks of methane (CH4 ) are critical for understanding global biogeochemical cycles and their role in climate change. A growing number of studies have reported that CH4 concentrations in cave ecosystems are depleted, leading to the notion that these subterranean environments may act as sinks for atmospheric CH4 . Recently, it was hypothesized that this CH4 depletion may be caused by...

of fasting are experienced by numerous subterranean (i.e. hypogean) aquatic organisms, as many groundwater ecosystems are characterized yearly by severely limited food supplies due to lack of autotrophic production and sporadic allochthonous input (Poulson, 1964; Hüppop, 1985; Hervant et al., 1997). Even in highly productive hypogean biotopes, food resources may be extremely patchy (Malard and ...

A review is made of linear slender-body methods for predicting the squat of a ship in shallow open water, dredged channels or canals. The results are summarized into a general formula based on Fourier transforms, and the method is extended to cater to stepped canals. An approximate solution for canals of arbitrary cross-section is proposed.

INTRODUCTION Oval-shaped root canals might represent a great challenge for proper disinfection. This study compared the capability of a newly developed instrument, the self-adjusting file (SAF), and rotary nickel-titanium (NiTi) instrumentation to eliminate Enterococcus faecalis populations from long oval root canals of extracted human teeth. As a secondary purpose, the ability of a modificatio...

Successful endodontic treatment requires thorough knowledge regarding each root canal system of any tooth and probability of extra canals should be considered. Second maxillary molar with two palatal root canals is not frequent and its incidence reported in literatures is about 0.4-2%. The present case report describes non-surgical retreatment of maxillary second mo-lar with two palatal root ca...