Purpose: The purpose of the present study was to investigate and compare the effect of different reciprocating movements and angles on the shaping ability of the WaveOne and the single-fle ProTaper F2 using cone beam computed tomography (CBCT).
Materials And Methods: The mesiobuccal canals of 40 extracted maxillary molars, with curvatures of 20 to 45° were coded and randomly divided into 4 equal experimental groups according to the instrument used (ProTaper F2 fle and Wa-veOne) and the reciprocation range, for both instruments, a 150° angle was used for cutting and a 30° angle was used for release. Group 1 - WaveOne primary 150° CCW rotation angle and 30° CW rotation angle; Group 2 - WaveOne 90° CCW rotation angle and 30° CW rotation angle; Group 3 - ProTaper F2 150° CW rotation angle and 30° CCW rotation angle; Group 4 - ProTaper F2 90° CW rotation angle and 30° CCW rotation angle. Canals were scanned before and after preparation using CBCT to evaluate the volumetric change, canal transportation and the canal centering ability at 2.6, 5.2 and 7.8 mm from the apex. The mean ± standard deviation (SD) values were analyzed, and the significance level was set at p ≤ 0.05.
Results: There was no significant difference in the amount of dentin removed among the experimental groups, except that WaveOne 150°CCW 30°CW significantly showed the least volume of dentin removed (0.40 ± 0.9) at 7.8 mm. All rotary systems tested in the different groups resulted in canal transportation in different directions at all examined levels. WaveOne 150°CCW 30°CW, demonstrated the lowest mean value of root canal transportation in both the mesial and furcal directions and in both the coronal and apical directions compared to the other groups. At the 7.8 level, WaveOne 150°CCW 30°CW yielded the highest mean centering ratio, whereas ProTaper F2 CW 150° CCW 30° yielded the lowest, statistically significant at p ≤ 0.05.
Conclusion: The results of the present study demonstrated that differences among various reciprocating motions and angles could affect the shaping ability of a single-fle Nickel-titanium (NiTi) instrument.
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http://dx.doi.org/10.5005/jp-journals-10024-1561 | DOI Listing |
J Spine Surg
December 2024
Department of Orthopedic Surgery, Chung Shan Hospital, Taipei, Taiwan.
Background: Prone lateral spinal surgery for simultaneous lateral and posterior approaches has recently been proposed to facilitate surgical room efficiency. The purpose of this study is to evaluate the feasibility and outcomes of minimally invasive prone lateral spinal surgery using a rotatable radiolucent Jackson table.
Methods: From July 2021 to June 2023, a consecutive series of patients who received minimally invasive prone lateral spinal surgery for various etiologies by the same surgical team were reviewed.
J Spine Surg
December 2024
Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, China.
Background: Vertebral body tethering (VBT) has shown improvements in coronal and sagittal plane correction in adolescent idiopathic scoliosis (AIS) patients, but axial correction over time remains unexplored. Three-dimensional (3D) spine reconstruction was used to analyse correctional changes in all spinal planes post VBT surgery.
Case Description: AIS subjects who underwent thoracic VBT surgery with a minimum 2-year follow-up were assessed.
Orthop J Sports Med
January 2025
Department of Orthopaedics, Balgrist University Hospital, University of Zurich, Zurich, Switzerland.
Background: Tibiofemoral rotation is an emerging parameter, especially in assessing patellofemoral instability. However, reference values in the literature are inconsistent regarding the used imaging modality and do not consider the effect of knee flexion during image acquisition.
Purpose: To analyze the differences in tibiofemoral rotation measurements between computed tomography (CT) and magnetic resonance imaging (MRI).
This Letter introduces a method for identifying the fast axis and phase retardation of wave plates by means of polarization common-path vortex interferometry. The technique utilizes a composite polarized vortex beam interacting with the wave plate under test. By analyzing the azimuth angle of the dark fringe in the interference pattern, the wave plate's characteristics are accurately extracted.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Orthopaedic, South China Hospital of Shenzhen University, Shenzhen, 518116, Guangdong, China.
Before patients begin out-of-bed exercises following internal fixation surgery for acetabular fractures, turning over in bed serves as a crucial intervention to mitigate complications associated with prolonged bed rest. However, data on the safety of this maneuver post-surgery are limited, and the biomechanical evidence remains unclear. This study aims to introduce a novel loading protocol designed to preliminarily simulate the action of turning over in bed and to compare the biomechanical properties of two fixation methods for acetabular fractures under this new protocol.
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