The aim of this study was to investigate the types of canal configurations and the incidence of a second mesiobuccal (MB2) canal in Korean maxillary molar mesiobuccal (MB) roots by analyzing cone-beam computed tomographic (CBCT) images.
Furthermore, based on the composite images, assessments were made according to the presence of different types of canal aberrations, such as apical zip, elbow, ledge and perforation.
Fit type was assessed by comparing the type of canal fill.
Yet engineers still disagreed on the type of canal that should be built, and they faced another problem of equal importance: how to manage the Chagres River, which rose in the northeast highland region of Panama and emptied into the Atlantic.
Although preliminary work started in 1904, little real progress was made because of disputes over the type of canal that should be built; not until 1906 was the high-level lock plan finally adopted, as opposed to the previously favoured sea-level plan.
They reported that the major type of canal shape for the IC is Y-morphology, with four other types - spindle-shaped, very large, cystic, and narrowed - existing as minor types [22].
The key was not to try to dig a Suez-type of canal, a great sea-level trench from ocean to ocean, but to create a lock-and-lake canal, where the ships are lifted up by a series of locks to a man-made lake, and then they sail across that lake, and then they are set back down on the other side by another series of locks.
As a confirmation of the former choice of relying on the EALs for the working length in all cases, being the same position for all procedures, Tsesis et al. (Tsesis et al. 2015) found the use of the EALs was not influenced by the status of the pulp tissue, although the precision of the length determination was based on the particular device and the type of canal irrigant.
For the purposes of this publication, only this type of canal will be considered.
It is difficult to directly compare the results of the present study with the available literature because they differ in too many aspects, including type of MTA, the assessment method, length of MTA fill, type of canal used, canal dimensions, ultrasonication time, and ultrasonic unit used.
