Introduction: This study investigated the effect of shaping parameters of 2 different configurations of middle mesial canals (MMCs) on the biomechanical behavior and life span of a mandibular first molar using finite element analysis (FEA).
Methods: A mandibular molar with an independent MMC and another with a confluent MMC were scanned via micro-computed tomography, and FEA models were produced. For each tooth, an intact model and 5 experimental models were produced that differed by parameters of how the MMC was shaped: unshaped MMC, 25/.04, 25/.06, 30/.04, and 30/.06. Cyclic loading of 50 N was applied on the occlusal surface in vertical and oblique scenarios, and the number of cycles until failure (NCF) was compared with the intact models. In addition, mathematical analyses evaluated the stress distribution patterns and calculated maximum von Mises and maximum principal stresses.
Results: For both the independent and confluent MMC models, shaping the MMC reduced the NCF. The lifelog percentage of models was inversely proportional with radicular shaping parameters during the vertical and oblique loading scenarios. The shaping size of 30/.06 resulted in lower lifelog percentage than the cases with shaping size of 25/.04 in both of the independent and confluent MMC models. For all models, oblique loading reduced NCF more than vertical loading.
Conclusion: Shaping the MMC should be kept as conservative as 25/.04. Also, whether the MMC is independent or confluent is a deciding factor in whether to increase the apical diameter or the root canal taper when larger shaping parameters are needed.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.joen.2023.03.007 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Shaping ability of NiTi reciprocating file systems R-motion and waveOne gold in mesial canals of mandibular molars; micro CT study.
Sci Rep
January 2025
Department of Endodontics, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia.
The preservation of the original configurations of root canals during endodontic preparation is crucial for treatment success. Nickel-titanium (NiTi) rotary systems have been refined to optimize canal shaping while minimizing iatrogenic errors. This study aimed to evaluate and compare the shaping efficacy of the novel R-Motion (RM) and the established WaveOne Gold (WG) systems using micro-computed tomography (micro-CT).
View Article and Find Full Text PDFDa Vinci's friction for granular media.
Sci Rep
January 2025
Civil and Environmental Engineering Department, Faculty of Engineering Sciences, Ben- Gurion University of the Negev, Beer-Sheva, Israel.
The concept of friction was integrated into the broader field of tribology in the 20th century. Here, we revive the older friction coefficient concept and show that it is the defining parameter for a family of granular materials. We show, for the first time, that kinetic friction coefficients of such systems can be described as a function of the lubricating fluid and the shape of the granules, without any fitting parameters.
View Article and Find Full Text PDFThermodynamic Stability in Transition Metal-Hydrogen Dications: Potential Energy Curves, Spectroscopic Parameters, and Bonding for VH.
J Comput Chem
January 2025
Universidade de São Paulo, Instituto de Química, Departamento de Química Fundamental, São Paulo, Brazil.
Seventeen electronic states of the dication VH were characterized by the SA-CASSCF/icMRCI methodology using very extended basis sets; 11 were described for the first time. Potential energy curves were constructed and the associated spectroscopic parameters evaluated. Triplet and quintet states correlating with the V + H channel are thermodynamic stable.
View Article and Find Full Text PDFUltrasonographic accuracy in evaluating response of clipped lymph nodes in targeted axillary dissection in breast cancer.
Sci Rep
January 2025
Department of Medical Pathology, Ege University Faculty of Medicine, Ege University Hospital, Bornova, İzmir, Turkey.
This study aimed to evaluate the diagnostic accuracy of ultrasonography in assessing the response of clipped axillary lymph nodes to neoadjuvant chemotherapy. Between February 2022 and September 2023, 43 patients who underwent axillary lymph node marking for targeted axillary dissection were retrospectively analyzed. Ultrasonography parameters such as the number, size, shape, cortical thickness, hilum status, and treatment response of the clipped lymph node were assessed.
View Article and Find Full Text PDFAdded Value of Dynamic Contrast-Enhanced Ultrasound Analysis for Differential Diagnosis of Small (≤20 mm) Solid Pancreatic Lesions.
Ultrasound Med Biol
January 2025
Department of Ultrasound, Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, Shanghai, China. Electronic address:
Objective: To evaluate the added value of dynamic contrast-enhanced ultrasound (DCE-US) analysis in pre-operative differential diagnosis of small (≤20 mm) solid pancreatic lesions (SPLs).
Methods: In this retrospective study, patients with biopsy or surgerical resection and histopathologically confirmed small (≤20 mm) SPLs were included. One wk before biopsy/surgery, pre-operative B-mode ultrasound and contrast-enhanced ultrasound were performed.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!