A New Method for Three-Dimensional Fracture Network Modelling for Trace Data Collected in a Large Sampling Window

Purpose: The aim of this study was to present a new method to analyze the three-dimensional accuracy of complete-arch dental impressions and verify the reliability of the method. Additionally, the accuracies of conventional and intraoral digital impressions were compared using the new method. Methods: A master model was fabricated using 14 milled polyetheretherketone cylinders and a maxillary acrylic model. Each cylinder was positioned and named according to its corresponding tooth position. Twenty-five definitive stone casts were fabricated using conventional impressions of the master model. An intraoral scanner was used to scan the master model 25 times to fabricate 25 digital models. A coordinate measuring machine was used to physically probe each cylinder in the master model and definitive casts. An inspection software was used to probe cylinders of digital models. A three-dimensional part coordinate system was defined and used to compute the centroid coordinate of each cylinder. Intraclass correlation coefficient (ICC) was evaluated to examine the reliability of the new method. Independent two sample t-test was performed to compare the trueness and precision of conventional and intraoral digital impressions (α = 0.05). Results: ICC results showed that, the new method had almost perfect reliability for the measurements of the master model, conventional and digital impression. Conventional impression showed more accurate absolute trueness and precision than intraoral digital impression for most of the tooth positions (p < 0.05). Conclusions: The new method was reliable to analyze the three-dimensional deviation of complete-arch impressions. Conventional impression was still more accurate than digital intraoral impression for complete arches.

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A new method for volumetric measurement of the normal female cervix by three‐dimensional transvaginal ultrasound

International Journal of Gynecology & Obstetrics ◽

10.1002/ijgo.13734 ◽

2021 ◽

Author(s):

Matija Prka ◽

Albert Despot ◽

Alemka Brnčić Fischer ◽

Herman Haller ◽

Ana Tikvica Luetić ◽

...

Keyword(s):

Transvaginal Ultrasound ◽

Three Dimensional ◽

New Method ◽

Normal Female ◽

Volumetric Measurement

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Three-dimensional analysis of the root canal preparation with Reciproc Blue®, WaveOne Gold® and XP EndoShaper®: a new method in vivo

BMC Oral Health ◽

10.1186/s12903-021-01450-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Javier Caviedes-Bucheli ◽

Nestor Rios-Osorio ◽

Diana Usme ◽

Cristian Jimenez ◽

Adriana Pinzon ◽

...

Keyword(s):

3D Reconstruction ◽

Root Canal ◽

Paired Comparison ◽

Three Dimensional ◽

New Method ◽

Root Canal Preparation ◽

Paired Data ◽

Before And After ◽

Student’S T

Abstract Background The purpose of this study was to evaluate the changes in canal volume after root canal preparation in vivo with 3 different single-file techniques (Reciproc-Blue®, WaveOne-Gold® and XP-EndoShaper®), with a new method using CBCT and 3D reconstruction. Methods In this prospective study, thirty human lower premolars from healthy patients were used, in which extraction was indicated for orthodontic reasons. All the teeth used were caries- and restoration-free with complete root development, without signs of periodontal disease or traumatic occlusion, and with only one straight canal (up to 25º curvature). Teeth were randomly divided into three different groups: Reciproc-Blue, WaveOne-Gold and XP-EndoShaper. CBCT scans before root canal preparation were used to create a 3D reconstruction with RHINOCEROS 5.0 software to assess the initial canal volume, and then compared with 3D reconstructions after canal preparation to measure the increase in canal volume. Student’s t test for paired data were used to determine statistically significant differences between the before and after canal volumes. Anova test was used to determine statistically significant differences in the percentage of canal volume increase between the groups and Tukey's post-hoc test were used to paired comparison. Results Reciproc-Blue showed the higher increase in canal volume, followed by WaveOne-Gold and XP-EndoShaper (p = 0.003). XP-EndoShaper did not show a statistically significant increase in canal volume after root canal preparation (p = 0.06). Conclusion With this model, Reciproc-Blue showed higher increase in root canal volume, followed by WaveOne-Gold, while XP-EndoShaper did not significantly increase root canal volume during preparation.

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Characterizing Reactive Transport Behavior in a Three-Dimensional Discrete Fracture Network

Transport in Porous Media ◽

10.1007/s11242-021-01568-4 ◽

2021 ◽

Author(s):

Thomas Sherman ◽

Guillem Sole-Mari ◽

Jeffrey Hyman ◽

Matthew R. Sweeney ◽

Daniel Vassallo ◽

...

Keyword(s):

Reactive Transport ◽

Three Dimensional ◽

Fracture Network ◽

Discrete Fracture Network ◽

Transport Behavior ◽

Discrete Fracture

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New method of holographic three-dimensional tracking of living cells exploiting their morphological properties

Digital Holography and Three-Dimensional Imaging ◽

10.1364/dh.2013.dtu2a.5 ◽

2013 ◽

Author(s):

Pasquale Memmolo ◽

Maria Iannone ◽

Maurizio Ventre ◽

Paolo Antonio Netti ◽

Andrea Finizio ◽

...

Keyword(s):

Three Dimensional ◽

Living Cells ◽

New Method ◽

Morphological Properties

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Comparing the perception with the reality of walking in a hilly environment: an accessibility method applied to a University campus in Hong Kong

Geospatial health ◽

10.4081/gh.2015.340 ◽

2015 ◽

Vol 10 (1) ◽

Cited By ~ 6

Author(s):

Guibo Sun ◽

Robert Haining ◽

Hui Lin ◽

Nicolas M. Oreskovic ◽

Jie He

Keyword(s):

Hong Kong ◽

Three Dimensional ◽

University Campus ◽

Network Modelling ◽

Walking Behavior ◽

Individual Perception ◽

Pedestrian Network ◽

Present Context ◽

Public Health Practitioners ◽

People’S Perceptions

The influence of hilliness on walking behavior could be a consequence of the real effect of the local topography, but individual perception of the difficulties associated with walking in a hilly environment may also be important. Previous studies have found that people’s perceptions do not necessarily match well with the realities of walking in hilly environments. There are a few methods that can be used to visualize the geography of that difference for use by urban planners and public health practitioners. A walking accessibility measure that allows comparison of perception and reality is proposed and implemented in this study. We note that difficulties in calculating accessibility measures in the present context arise primarily from problems with data quality, three-dimensional pedestrian network modelling and the adequacy of accessibility methods for describing and predicting walking behavior. We present practical strategies for addressing these issues using geographic information systems. Our method is illustrated by calculating accessibility for a hilly university campus in Hong Kong. Walking behaviors on, and people’s perceptions of, this hilly environment were obtained through walking diaries and a survey. The article concludes with suggested directions for the future development of walking accessibility measures along with some ideas about their applicability to the practice of planning and designing a walkable environment.

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Calculation of Horseshoe Vortex Flow Without Numerical Mixing

Volume 1: Turbomachinery ◽

10.1115/84-gt-241 ◽

1984 ◽

Author(s):

Joan G. Moore ◽

John Moore

Keyword(s):

Three Dimensional ◽

Leading Edge ◽

Horseshoe Vortex ◽

Companion Paper ◽

New Method ◽

Uniform Grid ◽

Grid Spacing ◽

Three Dimensional Flow ◽

Numerical Mixing ◽

Well Posed

The usefulness of three-dimensional flow calculations has frequently been obscured by the numerical mixing present in the calculation methods. This paper describes a new method of forming the finite difference momentum equations. The new method results in well posed equations which introduce no numerical mixing. It may be used with orthogonal or non-orthogonal grids and with uniform or highly non-uniform grid spacing. The method is demonstrated by comparing it with upwind differencing on the calculation of a simple example. It is then used in an elliptic pressure-correction calculation procedure to calculate a leading edge horseshoe vortex about a Rankine half body. The results compare well with the experimental data presented in a companion paper.

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