Introduction: The main objectives of this study were to generate individual finite element models of extracted human upper first premolars, and to simulate the distribution of the hydrostatic pressure in the periodontal ligament (PDL) of these models for evaluation of the risk of root resorption.
Methods: The individual extracted teeth were from a previous in vivo study that investigated root resorption after application of continuous intrusive forces. The results of experimental examination and simulations were compared on these identical tooth roots. The applied force system was 0.5N and 1.0N of intrusive force.
Results: The simulated results during intrusion of 0.5N showed regions near the apical thirds of the roots with hydrostatic pressure over the human capillary blood pressure. These regions correlated with the electron microscopies of previous studies performed in Brazil with the identical teeth. An increased force of 1.0N resulted in increased areas and magnitudes of the hydrostatic pressure.
Conclusions: The key parameter indicating beginning root resorption used in this study was an increased value for hydrostatic pressure in the PDL.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.cmpb.2008.09.004 | DOI Listing |
J Chem Theory Comput
January 2025
University of Bremen, Institute for Physical and Theoretical Chemistry, Leobener Str. 6, D-28359 Bremen, Germany.
To simulate the effects of high pressure on molecular and electronic structure, methods based on the polarizable continuum model have emerged as a serious contender to the conventionally employed periodic boundary conditions. In this work, we present a highly efficient integral-direct algorithm for the Gaussians On Surface Tesserae Simulate HYdrostatic Pressure (GOSTSHYP) method. We examine the efficiency of this implementation on large chains of α-d-glucose units.
View Article and Find Full Text PDFSci Rep
January 2025
School of Resources and Civil Engineering, Northeastern University, Shenyang, 110819, China.
Based on the symmetric initiation mechanism of double-wing cracks in coal rock mass induced by high-pressure electro-recoil water pressure, fracturing experiments have been performed on coal rock mass under different water pressures and discharge conditions using high-voltage electric pulse hydraulic fracturing devices. Combined with CT scans, the crack spatial distribution inside the post-break coal rock mass was analyzed and found that the edge of the water injection hole is prone to produce double-wing cracks along the drilling hole diameter. ABAQUS is used to verify the physical test and extend the test conditions, the geometric parameter change, morphological expansion rule and crack initiation mechanism of double-wing crack in coal rock mass under different discharge conditions and ground stress conditions are studied.
View Article and Find Full Text PDFBMC Biol
January 2025
CAS Key Laboratory of Marine Ecology and Environmental Sciences, and Center of Deep Sea Research, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071, China.
Background: Lindaspio polybranchiata, a member of the Spionidae family, has been reported at the Lingshui Cold Seep, where it formed a dense population around this nascent methane vent. We sequenced and assembled the genome of L. polybranchiata and performed comparative genomic analyses to investigate the genetic basis of adaptation to the deep sea.
View Article and Find Full Text PDFbioRxiv
December 2024
Department of Biology, University of Miami, 1301 Memorial Drive, Coral Gables, FL 33146.
Animals alter their behavior in response to changes in the environment. Upon encountering hyperosmotic conditions, the nematode worm initiates avoidance and cessation of egg-laying behavior. While the sensory pathway for osmotic avoidance is well-understood, less is known about how egg laying is inhibited.
View Article and Find Full Text PDFCells under high confinement form highly polarized hydrostatic pressure-driven, stable leader blebs that enable efficient migration in low adhesion, environments. Here we investigated the basis of the polarized bleb morphology of metastatic melanoma cells migrating in non-adhesive confinement. Using high-resolution time-lapse imaging and specific molecular perturbations, we found that EGF signaling via PI3K stabilizes and maintains a polarized leader bleb.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!