scholarly journals Micro computed tomography evaluation of Invisalign aligner thickness homogeneity

2021 ◽  
Author(s):  
Edoardo Mantovani ◽  
Simone Parrini ◽  
Emanuele Coda ◽  
Giovanni Cugliari ◽  
Nicola Scotti ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Descriptive Analysis ◽  
Linear Regression Analysis ◽  
Ct Scanning ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Multiplanar Reconstructions ◽  
Significant Difference ◽  
Student’S T ◽  
Molar Region

ABSTRACT Objectives To measure the thickness homogeneity of Invisalign (Align Technology Inc, San José, Calif) aligners with micro-computed tomography (micro-CT) scans. Materials and Methods Starting from micro-CT scanning of 20 different aligners, multiplanar reconstructions were obtained. An orthodontist blinded about the study measured aligner thickness in different regions (molar, canine, incisor) and in different sites (gingival–buccal, buccal, occlusal, lingual, and gingival–lingual). To assess various thicknesses in different aligner sites and regions, the sample was stratified into subgroups and linear regression analysis was performed. Results Descriptive analysis showed that mean thickness of aligners in the incisor region ranged from 0.582 mm to 0.639 mm, in the canine region from 0.569 mm to 0.644 mm, and in the molar region from 0.566 mm to 0.634 mm. Student's t-tests showed no significant differences in the aligner thickness of different regions when data were stratified by different sites. Student's t-tests showed significant differences in thickness homogeneity for the molar region when the data were stratified by tooth (mean difference = 0.068 mm; 95% confidence interval, 0.009–0.126 mm; P = .024). Conclusions Invisalign aligner thickness is characterized by small differences. The only significant difference was revealed in the molar region where thickness of the gingival–lingual edge is significantly thinner than that measured at the occlusal aspect. From a clinical perspective, the results of the present study could be considered to explain the reduced predictability of several orthodontic tooth movements in the molar region.

MicroCT protocols for scanning of embryos and juvenile Hexaplex trunculus v1

2021 ◽  
Author(s):  
Eva Chatzinikolaou ◽  
Kleoniki Keklikoglou
Keyword(s):  
Computed Tomography ◽  
High Resolution ◽  
3D Imaging ◽  
Imaging Technique ◽  
Ct Scanning ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Gastropod Species ◽  
Biological Studies ◽  
Hexaplex Trunculus

Micro-computed tomography (micro-CT) is a high-resolution 3D-imaging technique which is now increasingly applied in biological studies focusing on taxonomy and functional morphology. The creation of virtual representations of specimens can increase availability of otherwise underexploited and inaccessible samples. This protocol aims to standardise micro-CT scanning procedures for embryos and juveniles of the marine gastropod species Hexaplex trunculus.

The endocranial anatomy of Gogonasus andrewsae Long, 1985 revealed through micro CT-scanning

2014 ◽  
Vol 105 (1) ◽  
pp. 9-34 ◽  
Author(s):  
Timothy Holland
Keyword(s):  
Computed Tomography ◽  
Blood Vessels ◽  
Western Australia ◽  
Nasal Septum ◽  
Ct Scanning ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
New Research ◽  
Nasal Capsule

ABSTRACTMicro computed tomography has revealed as yet undescribed internal braincase anatomy of the tetrapodomorph fish Gogonasus andrewsae from the Frasnian Gogo Formation, Paddy's Valley, Kimberley Region, Western Australia. The complete material, including the cranial cavities and channels for blood vessels and nerves, reveals several notable features inside the endocranium. The ethmosphenoid unit includes a median capsule, which lies underneath the median postrostral and rostral series. Based on innervation and association with cutaneous vessels, potential electroreceptive function is inferred for this capsule. Several regions of poor ossification, including foramina for the glossopharyngeal and abducens nerves, as well as the apparent suture separating the ethmoid from the sphenoid portions of the braincase, are possibly indicative of early ontogenetic features. Former interpretations of the course for the superficial ophthalmic nerve inside the nasal capsule of Osteolepis and Gyroptychius may be incorrect, with new research supporting a path through the nasal septum, as in Gogonasus.

scholarly journals Adaptation of the single-cone in prepared long oval-shaped canals: a micro-computed tomography study

2021 ◽  
Vol 10 (15) ◽  
pp. e444101523301
Author(s):  
Christianne Velozo ◽  
Hugo Dantas ◽  
Basílio Rodrigues Vieira ◽  
Frederico Barbosa de Sousa ◽  
Victor Felipe Farias do Prado ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Root Canal ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Mean Values ◽  
Root Canals ◽  
Gutta Percha ◽  
Working Length ◽  
Single Cone ◽  
Student’S T

The present study aimed to evaluate adaptation of the single gutta-percha cone on root canal walls prepared with the two systems, the XP-endo Shaper (XPS; FKG Dentaire, La Chaux-de-Fonds, Switzerland) and ProTaper Next systems (PTN; Dentsply Sirona, Ballaigues, Switzerland) by using micro-computed tomography (micro-CT) technology. Twenty long oval-shaped canals in mandibular incisors were scanned by micro-CT (Skyscan 1172; Bruker microCT, Kontich, Belgium). Two groups were divided into (n = 10) according to the canal preparation protocol: XPS group with an extra 45 s of instrumentation and PTN group. A gutta percha cone, with respect to the protocol used for each group (size 40, .04 taper, XPS and size 40, .06 taper, PTN) was adapted to the canal at the working length of all the samples, and all root canals were filled, using the single-cone technique. The mean values for volume of voids and percentage relative to the mentioned space were correspondingly higher in XPS group than they were PTN group, mean values for volume of voids (3.61 mm3 - 1.92 mm3) and for percentage of voids (39.25% - 23.28%), respectively, significant differences were recorded (p < 0.05) between the two groups (XPS and PTN, Student’s-t test for homogenous variances and Mann–Whitney test). The canals prepared with XPS, in the procedure performed with an extra 45 s of instrumentation, showed a higher volume of voids than those prepared with the PTN system, in obturation of the root canal with the single cone technique.

scholarly journals A Nondestructive Method of Measuring Zebrafish Adipose Tissue Based on Micro-Computed Tomography (Micro-CT)

2021 ◽  
Vol 11 (22) ◽  
pp. 10510
Author(s):  
Xin Wang ◽  
Guangxin Wang ◽  
Yuan Xiao ◽  
Yanxia Zuo ◽  
Fang Zhou
Keyword(s):  
Computed Tomography ◽  
Adipose Tissue ◽  
Lipid Metabolism ◽  
Abdominal Cavity ◽  
Ct Scanning ◽  
Fat Distribution ◽  
Nondestructive Method ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Scanning Method

Due to problems such as unbalanced intake of nutrients or excessive intake of energy, cultured fish accumulate fat in places such as the abdominal cavity, liver, and muscle, resulting in fatty liver, reducing the quality of fish meat, and even causing many fish deaths, resulting in losses to aquaculture production. Therefore, research on lipid metabolism in fish is important and has attracted increasing attention. The detection of fish body fat distribution and content is a key to such research. The existing methods for detecting fat distribution and content in fish have limitations, such as cumbersome procedures and damage to fish tissues, and thus, is imperative to develop a simple, fast, nondestructive fat detection technology. Taking zebrafish as the research material, this study established an imaging technology for the rapid and nondestructive detection of the fat distribution and content of fish by micro-computed tomography (micro-CT), optimized the fat CT-scanning method, determined the steps of fat quantitation in the CTAn data processing software, and constructed a three-dimensional (3D) model of zebrafish adipose tissue. This technology reveals the distribution of fish adipose tissue in an all-round way, and thus, it will play an important role in the study of lipid metabolism in fish.

MicroCT protocols for scanning egg capsules of Hexaplex trunculus v1

2021 ◽  
Author(s):  
Eva Chatzinikolaou ◽  
Kleoniki Keklikoglou
Keyword(s):  
Computed Tomography ◽  
3D Imaging ◽  
Imaging Technique ◽  
Ct Scanning ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Gastropod Species ◽  
Egg Capsules ◽  
Biological Studies ◽  
Hexaplex Trunculus

Micro-computed tomography (micro-CT) is a high-resolution 3D-imaging technique which is now increasingly applied in biological studies focusing on taxonomy and functional morphology. The creation of virtual representations of specimens can increase availability of otherwise underexploited and inaccessible samples. This protocol aims to standardise micro-CT scanning procedures for the egg capsules of the marine gastropod species Hexaplex trunculus.

scholarly journals Comparison of Two Techniques for Selection of Master Gutta-Percha Cone Using Micro-Computed Tomography

2013 ◽  
Vol 24 (4) ◽  
pp. 367-370 ◽  
Author(s):  
Joao Manoel Silva-Filho ◽  
Aline Evangelista Souza-Gabriel ◽  
Graziela Bianchi Leoni ◽  
Samuel Henrique Camara De-Bem ◽  
Edson Alfredo ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Conventional Technique ◽  
Filling Material ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Root Canals ◽  
Gutta Percha ◽  
Working Length ◽  
Significant Difference ◽  
Material Volume

This study used micro-computed tomography (micro-CT) to evaluate the fit of the master gutta-percha cone at time of cone fit, gutta-percha volume in the filling material, and the filling material volume in relation to the canal at the apical limit of the working length. Root canals of 20 maxillary central incisors were prepared with rotary instruments and distributed into two groups (n=10). The gutta-percha cone tip was either plasticized (apical thermal impression technique - ATI) or not (conventional technique - CT), and its apical fit was checked. The apical 1 mm of working length was examined with a micro-CT, canals were filled with gutta-percha and sealer, and new micro-CT scans were obtained. In CT, gutta-percha filled 35.83 ± 15.05% of the canal at cone selection and 38.72 ± 11.64% after filling. In ATI, these values were 23.14 ± 7.74% and 26.98 ± 20.40%, respectively. Gutta-percha volume in the filling material, and filling material volume in relation to the canal were, respectively, 61.28 ± 11.64% and 87.76 ± 9.98% for CT, and 73.00 ± 20.41% and 89.96 ± 9.08% for ATI. No significant difference was found between cone selection and after canal filling, for either CT (p=0.593) or ATI (p=0.4975). The techniques did not differ significantly with respect to gutta-percha volume in the filling material (p=0.132) and filling material volume in relation to the canal (p=0.612). An ideal fit of the master gutta-percha cone at working length was not achieved regardless of the cone selection technique, and the material-filled area was similar for both techniques.

scholarly journals Quantitative Analysis of the Anatomy of Mesial Roots of Mandibular First Molars with Vertucci Type I Root Canal Configuration by Means of Micro-Computed Tomography

2020 ◽  
Vol 10 (1) ◽  
pp. 17-21
Author(s):  
Ali Keleş ◽  
Cangül Keskin
Keyword(s):  
Computed Tomography ◽  
Quantitative Analysis ◽  
Root Canal ◽  
Visual Analysis ◽  
Descriptive Analysis ◽  
Type I ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Cross Sectional ◽  
Root Canals

Aim:  This study aimed to evaluate root canal morphology of Vertucci type I root canal configuration detected in mesial roots of mandibular first molar teeth using micro-computed tomography (Micro-CT). Methodology: Micro-CT datasets of 269 specimens were evaluated for the detection of specimens with Vertucci type I root canal configuration for further analysis. Major and minor diameter, area, perimeter and roundness of root canal cross-sections at the beginning and midline of each root thirds were measured and recorded. The presence of apical delta, accessory canals, and deviation of major apical foramen from anatomical apex were investigated. Data was analyzed using descriptive analysis, ANOVA-Tukey and Kruskal-Wallis H-Wilcoxon signed-rank tests. Results: Vertucci type I canal configuration was present in the 4.46% of the specimens. The specimens often showed accessory root canals (50%) and apical deltas (41,6%). From the visual analysis of the 3D and 2D images, significant differences were detected among coronal, middle and apical thirds of the specimens regarding major and minor diameter, area, perimeter and roundness (P < 0.05). Conclusion: Three- and two-dimensional analyses of mesial roots with Vertucci type I canal configuration indicated that this type of configuration presents large buccolingual diameters with long oval shape and has isthmus at coronal and middle thirds. At the apical third the root canals often terminate in an oval cross sectional shape.   How to cite this article: Keles A, Keskin C. Quantitative analysis of the anatomy of mesial roots of mandibular first molars with Vertucci type I root canal configuration by means of micro-computed tomography. Int Dent Res 2020;10(1):17-21. https://doi.org/10.5577/intdentres.2020.vol10.no1.4   Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

scholarly journals Presence of voids after three obturation techniques in band‐shaped isthmuses: a micro‐computed tomography study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Pengfei Zhang ◽  
Keyong Yuan ◽  
Qiaoqiao Jin ◽  
Fen Zhao ◽  
Zhengwei Huang
Keyword(s):  
Computed Tomography ◽  
Continuous Wave ◽  
Ct Scanning ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Filling Materials ◽  
Gutta Percha ◽  
Molar Teeth ◽  
Void Volumes

Abstract Background The objective of the present micro-computed tomography (micro-CT) study was to assess the presence of voids in band-shaped isthmuses obturated using three different filling techniques. Methods Twenty-four artificial molar teeth with a band-shaped isthmus were allocated to three groups (n = 8) for obturation, according to the filling technique: single-cone (SC), continuous wave of condensation (CWC) or lateral condensation (LC). Obturation was performed with gutta-percha (GP) cones and iRoot SP (Innovative Bioceramix, Vancouver, Canada). Post-filling micro-CT scanning was performed. The percentage of filling materials and void volumes were calculated in the isthmus areas and data were analyzed using one-way ANOVA and Tukey tests. Results The mean percentage of void volumes and corresponding filling percentages in the isthmus areas after obturation in the SC groups was 22.98 % ± 1.19 %, 77.02 % ± 1.19 %; in the CWC groups 10.46 % ± 2.28 %, 89.54 % ± 2.28 %; and in the LC groups was 13.14 % ± 1.85 %, 86.86 % ± 1.85 %, respectively. Conclusions In band-shaped isthmus area, the obturation quality of CWC was superior to SC and LC techniques.

scholarly journals How biocompatible haemodialysers can conquer the need for systemic anticoagulation even in post-dilution haemodiafiltration: a cross-over study

2020 ◽  
Author(s):  
Floris Vanommeslaeghe ◽  
Iván Josipovic ◽  
Matthieu Boone ◽  
Arjan van der Tol ◽  
Annemie Dhondt ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Relative Number ◽  
Ct Scanning ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Scanning Technique ◽  
Half Dose ◽  
Systemic Anticoagulation

Abstract Background While systemic anticoagulation is most widely used in haemodialysis (HD), contraindications to its use might occur in particular settings. The Solacea™ haemodialyser with an asymmetric triacetate membrane claims improved biocompatibility and has already shown promising results when used in combination with only half dose of anticoagulation. To quantify the performance of the Solacea™ when further decreasing anticoagulation to zero, fibre blocking was assessed by micro-computed tomography (micro-CT). Methods Ten maintenance HD patients underwent six dialysis sessions at midweek using a Solacea™ 19H dialyser, consecutively in pre-dilution haemodiafiltration (pre-HDF), HD and post-dilution HDF (post-HDF). After the first three sessions with only a quarter of their regular anticoagulation dose (one-quarter), the last three sessions were performed without anticoagulation (zero). Dialyser fibre blocking was quantified in the dialyser outlet potting using a 3D micro-CT scanning technique post-dialysis. Results Even in case of reduced (one-quarter) anticoagulation, the relative number of open fibres post-dialysis was almost optimal, i.e. 0.96 (0.87–0.99) with pre-HDF, 0.99 (0.97–0.99) with HD and 0.97 (0.92–0.99) with post-HDF. Fibre patency was mildly decreased for pre-HDF and HD when anticoagulation was decreased from one-quarter to zero, i.e. to 0.76 (0.61–0.85) with pre-HDF (P = 0.004) and to 0.80 (0.77–0.89) with HD (P = 0.013). Comparing the results for zero anticoagulation, post-HDF [i.e. 0.94 (0.82–0.97)] performed as well as HD and pre-HDF. Conclusions The Solacea™ dialyser provides promising results for use in conditions where systemic anticoagulation is contraindicated. Post-HDF, although inducing haemoconcentration in the dialyser, is equally effective for fibre patency in case of zero anticoagulation as pre-HDF and HD when using Solacea™.

scholarly journals Exploring the use of micro-computed tomography (micro-CT) in the taxonomy of sea cucumbers: a case-study on the gravel sea cucumber Neopentadactyla mixta (Östergren, 1898) (Echinodermata, Holothuroidea, Phyllophoridae)

ZooKeys ◽  
2021 ◽  
Vol 1054 ◽  
pp. 173-184
Author(s):  
Yves Samyn ◽  
Gontran Sonet ◽  
Cedric d'Udekem d'Acoz
Keyword(s):  
Computed Tomography ◽  
Sea Cucumber ◽  
Ct Scanning ◽  
The Novel ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Base Pairs ◽  
Integrative Study ◽  
Calcareous Ring

Sea cucumber taxonomy and systematics has in the past heavily relied on gross external and internal anatomy, ossicle assemblage in different tissues, and molecular characterisation, with coloration, habitat, and geographical and bathymethric distribution also considered important parameters. In the present paper, we made these observations and techniques in detail and complemented them with the novel technique of micro-computed tomography of the calcareous ring. We investigated a single European species, the so-called gravel sea cucumber, Neopentadactyla mixta (Östergren, 1898), using recently collected material from the Chausey Islands, Normandy, France. We redescribed the species, illustrated its ossicle assemblage through scanning electron microscopy, and visualised the calcareous ring through stacking photography and through micro-CT scanning. Additionally, a DNA fragment of 955 base pairs of the 18S ribosomal RNA gene was sequenced from one specimen, which showed a high similarity with the only sequence of N. mixta publicly available. We completed this integrative study by providing a detailed distribution of the occurrence of N. mixta based on published, verifiable accounts.

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