I hope that many physicians caring for patients with acute chest pain will actually take the time to read the new 2011 ESC guidelines for the management of acute coronary syndromes
in patients presenting without persistent ST-segment elevation. Certainly, application of the principles highlighted in there will help them in their daily clinical work.”
“Objective. The purpose of this study was to compare the shaping ability (apical transportation and straightening) of 3 nickel-titanium rotary instruments (ProTaper Universal, Hero 642 Apical, FlexMaster) with noncutting tips in curved root canals of extracted human teeth using cone beam computed tomography (CBCT).
Study design. Sixty mesiobuccal root canals of maxillary molars with curvatures of 25 degrees to 47 degrees were equally divided into 3 groups and embedded PD98059 in silicone impression material. The
root canals were scanned using CBCT (Next Generation i-CAT) and after scanning working length was determined with a hand file to preserve the original curvature. After preparation, teeth were placed learn more into their original positions on the silicone impression material and postinstrumentation scans were performed using the same parameters (4-cm field of view at 0.125-mm voxel). Pre- and postinstrumentation images obtained from root cross-sections located 2, 3, and 4 mm above the apical foramen were compared using Adobe Photoshop software. Transportation was measured by superimposition of final and initial images. Any distance (mm) between prepared and anatomic canal centers was defined as apical transportation. Canal curvatures were measured before and after instrumentation using computed tomography and images were exported to ImageJ software. Differences in the degree and radius of curvature were regarded as straightening. Data were analyzed by ANOVA.
Results. Mean transportation
values were 0.10 +/- 0.03 mm for ProTaper Universal, 0.09 +/- 0.03 mm for Hero 642 Apical, and 0.07 +/- 0.02 mm for FlexMaster, and the differences were not significant. Mean values for straightening among the groups were not significantly different (P > .05). CGP 41251 The performances of all instruments were similar.
Conclusion. Apical transportation occurred with all the instruments despite their noncutting tips. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2011; 111: 244-250)”
“X-ray scatter dark field imaging based on the Talbot-Lau interferometer allows for the measurement of ultra-small angle x-ray scattering. The latter is related to the variations in the electron density in the sample at the sub- and micron-scale. Therefore, information on features of the object below the detector resolution can be revealed.
In this article, it is demonstrated that scatter dark field imaging is particularly adapted to the study of a material’s porosity. An interferometer, optimized for x-ray energies around 50 keV, enables the investigation of aluminum welding with conventional laboratory x-ray tubes.