Dimorphism in Dental Tissues: Sex differences in Archaeological Individuals for Multiple Tooth Types

AbstractObjectivesDimorphism in the dentition has been observed in human populations worldwide. However, research has largely focused on traditional linear crown measurements. As imaging systems, such as micro-computed tomography (micro-CT), become increasingly more accessible, new dental measurements such as dental tissue size and proportions can be obtained. This research investigates the variation of dental tissues and proportions by sex in archaeological samples.Materials and MethodsUpper and lower first incisor to second premolar tooth rows were obtained from 30 individuals (n=300), from 3 archaeological samples. The teeth were micro-CT scanned and surface area and volumetric measurements were obtained from the surface meshes extracted. Dental wear was also recorded and differences between sexes determined.ResultsEnamel and crown measurements were found to be larger in females. Conversely, dentine and root measurements were larger in males.DiscussionThe findings support the potential use of dental tissues to estimate sex of individuals from archaeological samples, whilst also indicating that individuals aged using current dental ageing methods may be under- or over-aged due to sex differences in enamel thickness.

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Injectable Biomaterials for Dental Tissue Regeneration

International Journal of Molecular Sciences ◽

10.3390/ijms21103442 ◽

2020 ◽

Vol 21 (10) ◽

pp. 3442 ◽

Cited By ~ 4

Author(s):

Håvard Jostein Haugen ◽

Poulami Basu ◽

Mousumi Sukul ◽

João F Mano ◽

Janne Elin Reseland

Keyword(s):

Tissue Engineering ◽

Tissue Regeneration ◽

Narrative Review ◽

Pivotal Role ◽

Dental Tissue ◽

Dental Tissues ◽

Different Types ◽

Oral Area ◽

Potential Use

Injectable biomaterials scaffolds play a pivotal role for dental tissue regeneration, as such materials are highly applicable in the dental field, particularly when compared to pre-formed scaffolds. The defects in the maxilla-oral area are normally small, confined and sometimes hard to access. This narrative review describes different types of biomaterials for dental tissue regeneration, and also discusses the potential use of nanofibers for dental tissues. Various studies suggest that tissue engineering approaches involving the use of injectable biomaterials have the potential of restoring not only dental tissue function but also their biological purposes.

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A micro-computed tomography evaluation of the change in volume of different bulk-fill composite materials caused by polymerization shrinkage

International Dental Research ◽

10.5577/intdentres.2021.vol11.no2.4 ◽

2021 ◽

Vol 11 (2) ◽

pp. 75-82

Author(s):

Suzan Cangül ◽

Özkan Adıgüzel ◽

Savaş Sağmak ◽

Begüm Evran

Keyword(s):

Computed Tomography ◽

Composite Materials ◽

Class Ii ◽

Ct Images ◽

Composite Resins ◽

Micro Ct ◽

Micro Computed Tomography ◽

Dental Tissue ◽

Polymerization Shrinkage ◽

Native Speakers Of English

Aim: Composite resins contain different monomers and fillers that are directly affected by polymerization shrinkage. Therefore, an accurate and reliable method is needed to measure the volume changes. The aim of this study was to evaluate the amount of volume change associated with polymerization shrinkage in four different bulk-fill composite materials in class II restorations using a micro-CT device, which has high resolution and provides 3-dimensional images. Methodology: A total of 40 human 3rd molar teeth were used. First, standard class II cavities were opened on the mesial surfaces of all the teeth, and then the first micro-CT images were obtained. The same adhesive material was applied to all the teeth. The teeth were then separated into four groups, and a different bulk-fill composite was applied to each group; Filtek (FTK), X-tra Fil (XTF), Tetric Evo Ceram (TEC), and Filtek One (FLO) and the second micro-CT images were obtained. Then after polymerization of the materials, the final micro-CT images were taken, and analyses were made according to the scanning results. The Kruskal Wallis and Mann Whitney U-tests were used in the statistical evaluation of the data. Results: The volumetric gap formed after polymerization of the composite resins was not determined to be statistically significant (p>0.05). Conclusion: The volumetric difference (%) between the composite resin and the dental tissue following polymerization was seen to be greatest in XTF and least in FTK. It was concluded that the volumetric gap caused by the polymerization shrinkage of the tested materials may be due to the structure of the material. How to cite this article: Cangül S, Adıgüzel Ö, Sağmak S, Evran B. A micro-computed tomography evaluation of the change in volume of different bulk-fill composite materials caused by polymerization shrinkage. Int Dent Res 2021;11(2):75-82. https://doi.org/10.5577/intdentres.2021.vol11.no2.4 Linguistic Revision: The English in this manuscript has been checked by at least two professional editors, both native speakers of English.

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Observation of the Pulp Chamber of Maxillary First Premolars: A Micro-computed Tomographic Study

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405615666191016125937 ◽

2020 ◽

Vol 16 (3) ◽

pp. 224-230

Author(s):

Gozde Serindere ◽

Ceren Aktuna Belgin ◽

Kaan Orhan

Keyword(s):

Root Canal ◽

Age Groups ◽

Slice Thickness ◽

Micro Ct ◽

Micro Computed Tomography ◽

Pulp Chamber ◽

Anatomical Structures ◽

Computed Tomographic ◽

The Mean ◽

Chamber Floor

Background: There are a few studies about the evaluation of maxillary first premolars internal structure with micro-computed tomography (micro-CT). The aim of this study was to assess morphological features of the pulp chamber in maxillary first premolar teeth using micro- CT. Methods: Extracted 15 maxillary first premolar teeth were selected from the patients who were in different age groups. The distance between the pulp orifices, the diameter of the pulp and the width of the pulp chamber floor were measured on the micro-CT images with the slice thickness of 13.6 µm. The number of root canal orifices and the presence of isthmus were evaluated. Results: The mean diameter of orifices was 0.73 mm on the buccal side while it was 0.61 mm on palatinal side. The mean distance between pulp orifices was 2.84 mm. The mean angle between pulp orifices was -21.53°. The mean height of pulp orifices on the buccal side was 4.32 mm while the mean height of pulp orifices on the palatinal side was 3.56 mm. The most observed shape of root canal orifices was flattened ribbon. No isthmus was found in specimens. Conclusion: Minor anatomical structures can be evaluated in more detail with micro-CT. The observation of the pulp cavity was analyzed using micro-CT.

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Micro-Computed Tomography Analysis of Subchondral Bone Regeneration Using Osteochondral Scaffolds in an Ovine Condyle Model

Applied Sciences ◽

10.3390/app11030891 ◽

2021 ◽

Vol 11 (3) ◽

pp. 891

Author(s):

Taylor Flaherty ◽

Maryam Tamaddon ◽

Chaozong Liu

Keyword(s):

Computed Tomography ◽

Bone Regeneration ◽

Subchondral Bone ◽

Volume Ratio ◽

Bone Volume ◽

Osteochondral Defects ◽

Micro Ct ◽

Micro Computed Tomography ◽

Trabecular Thickness ◽

Osteochondral Scaffold

Osteochondral scaffold technology has emerged as a promising therapy for repairing osteochondral defects. Recent research suggests that seeding osteochondral scaffolds with bone marrow concentrate (BMC) may enhance tissue regeneration. To examine this hypothesis, this study examined subchondral bone regeneration in scaffolds with and without BMC. Ovine stifle condyle models were used for the in vivo study. Two scaffold systems (8 mm diameter and 10 mm thick) with and without BMC were implanted into the femoral condyle, and the tissues were retrieved after six months. The retrieved femoral condyles (with scaffold in) were examined using micro-computed tomography scans (micro-CT), and the micro-CT data were further analysed by ImageJ with respect to trabecular thickness, bone volume to total volume ratio (BV/TV) ratio, and degree of anisotropy of bone. Statistical analysis compared bone regeneration between scaffold groups and sub-set regions. These results were mostly insignificant (p < 0.05), with the exception of bone volume to total volume ratio when comparing scaffold composition and sub-set region. Additional trends in the data were observed. These results suggest that the scaffold composition and addition of BMC did not significantly affect bone regeneration in osteochondral defects after six months. However, this research provides data which may guide the development of future treatments.

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Additive-manufactured Ti-6Al-4 V/Polyetheretherketone composite porous cage for Interbody fusion: bone growth and biocompatibility evaluation in a porcine model

BMC Musculoskeletal Disorders ◽

10.1186/s12891-021-04022-0 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Pei-I Tsai ◽

Meng-Huang Wu ◽

Yen-Yao Li ◽

Tzu-Hung Lin ◽

Jane S. C. Tsai ◽

...

Keyword(s):

Bone Formation ◽

Bone Growth ◽

Lumbar Fusion ◽

High Porosity ◽

Ti Alloy ◽

Micro Ct ◽

Micro Computed Tomography ◽

Intervertebral Fusion ◽

Porous Ti ◽

Peek Composite

Abstract Background We developed a porous Ti alloy/PEEK composite interbody cage by utilizing the advantages of polyetheretherketone (PEEK) and titanium alloy (Ti alloy) in combination with additive manufacturing technology. Methods Porous Ti alloy/PEEK composite cages were manufactured using various controlled porosities. Anterior intervertebral lumbar fusion and posterior augmentation were performed at three vertebral levels on 20 female pigs. Each level was randomly implanted with one of the five cages that were tested: a commercialized pure PEEK cage, a Ti alloy/PEEK composite cage with nonporous Ti alloy endplates, and three composite cages with porosities of 40, 60, and 80%, respectively. Micro-computed tomography (CT), backscattered-electron SEM (BSE-SEM), and histological analyses were performed. Results Micro-CT and histological analyses revealed improved bone growth in high-porosity groups. Micro-CT and BSE-SEM demonstrated that structures with high porosities, especially 60 and 80%, facilitated more bone formation inside the implant but not outside the implant. Histological analysis also showed that bone formation was higher in Ti alloy groups than in the PEEK group. Conclusion The composite cage presents the biological advantages of Ti alloy porous endplates and the mechanical and radiographic advantages of the PEEK central core, which makes it suitable for use as a single implant for intervertebral fusion.

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Using micro-computed tomography to reveal the anatomy of adult Diaphorina citri Kuwayama (Insecta: Hemiptera, Liviidae) and how it pierces and feeds within a citrus leaf

Scientific Reports ◽

10.1038/s41598-020-80404-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Javier Alba-Tercedor ◽

Wayne B. Hunter ◽

Ignacio Alba-Alejandre

Keyword(s):

Computed Tomography ◽

Significant Advance ◽

Micro Ct ◽

Diaphorina Citri ◽

Ct Reconstruction ◽

Internal Anatomy ◽

Micro Computed Tomography ◽

Citrus Leaf ◽

Teaching Aids ◽

Adult Feeding

AbstractThe Asian citrus psyllid (ACP), Diaphorina citri, is a harmful pest of citrus trees that transmits Candidatus Liberibacter spp. which causes Huanglongbing (HLB) (citrus greening disease); this is considered to be the most serious bacterial disease of citrus plants. Here we detail an anatomical study of the external and internal anatomy (excluding the reproductive system) using micro-computed tomography (micro-CT). This is the first complete 3D micro-CT reconstruction of the anatomy of a psylloid insect and includes a 3D reconstruction of an adult feeding on a citrus leaf that can be used on mobile devices. Detailed rendered images and videos support first descriptions of coxal and scapus antennal glands and sexual differences in the internal anatomy (hindgut rectum, mesothoracic ganglion and brain). This represents a significant advance in our knowledge of ACP anatomy, and of psyllids in general. Together the images, videos and 3D model constitute a unique anatomical atlas and are useful tools for future research and as teaching aids.

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A Micro-Computed Tomography Comparison of the Porosity in Additively Fabricated CuCr1 Alloy Parts Using Virgin and Surface-Modified Powders

Materials ◽

10.3390/ma14081995 ◽

2021 ◽

Vol 14 (8) ◽

pp. 1995

Author(s):

Mirko Sinico ◽

Suraj Dinkar Jadhav ◽

Ann Witvrouw ◽

Kim Vanmeensel ◽

Wim Dewulf

Keyword(s):

High Energy ◽

High Energy Density ◽

Micro Ct ◽

Micro Computed Tomography ◽

Powder Bed ◽

Metallurgical Defects ◽

Ct Analysis ◽

Ct Data ◽

Surface Modified ◽

Fusion Pores

Recently, the use of novel CuCr1 surface-modified powder for reliable laser powder-bed fusion (LPBF) manufacturing has been proposed, enabling a broader LPBF processing window and longer powder storage life. Nevertheless, virgin CuCr1 powder is also LPBF processable, on the condition that a high-energy density is employed. In this work, we compare two dense specimens produced from virgin and surface-modified CuCr1 powder. Furthermore, a third sample fabricated from surface-modified powder is characterized to understand an abnormal porosity content initially detected through Archimedes testing. Utilizing high-resolution micro-CT scans, the nature of the defects present in the different samples is revealed. Pores are analyzed in terms of size, morphology and spatial distribution. The micro-CT data reveal that the virgin CuCr1 dense specimen displays keyhole pores plus pit cavities spanning multiple layer thicknesses. On the other hand, the sample fabricated with the surface-modified CuCr1 powder mainly contains small and spherical equi-distributed metallurgical defects. Finally, the CT analysis of the third specimen reveals the presence of a W contamination, favoring lack-of-fusion pores between subsequent LPBF layers. The LPBF melting mode (keyhole or conductive), the properties of the material, and the potential presence of contaminants are connected to the different porosity types and discussed.

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Effects of pre-extraction intermittent PTH administration on extraction socket healing in bisphosphonate administered ovariectomized rats

Scientific Reports ◽

10.1038/s41598-020-79787-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jae-Young Kim ◽

Hyo-Won Jang ◽

Jung-In Kim ◽

In-Ho Cha

Keyword(s):

Tooth Extraction ◽

Bisphosphonate Therapy ◽

Ovariectomized Rats ◽

Control Group ◽

Micro Ct ◽

Micro Computed Tomography ◽

Extraction Socket ◽

Before And After ◽

Socket Healing ◽

Positive Effect

AbstractThe purpose of this study was to investigate the effect of administering intermittent parathyroid hormone (iPTH) before tooth extraction versus after tooth extraction on the risk of developing MRONJ in experimental animal model. Twenty-five ovariectomized rats received 6 weeks of bisphosphonate therapy. They were classified into 3 groups, based on the timing of the medication, as Control, Pre-PTH and Post-PTH groups. For Control group, normal saline was administered before and after tooth extraction. iPTH was administered during 4 weeks before tooth extraction for Pre-PTH group and after tooth extraction for Post-PTH group. The animals were euthanized 8 weeks after tooth extraction. Macroscopic, histological, micro-computed tomography (micro-CT), and histomorphometric examinations were conducted. The incidences of impaired healing were 11.11% both in Pre-PTH and Post-PTH groups, which was lower than the Control group (42.86%). Bone healing in the extraction socket, based on micro-CT and histomorphometry evaluations, was best in Post-PTH and worst in Control group. The Pre-PTH group showed moderate healing pattern. Despite of limitations in this study, the authors identified Pre-PTH group seems to have positive effect on extraction socket healing. With regard to timing, administering iPTH after tooth extraction was superior to applying it before tooth extraction.

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Sex differences in skinfold variability across human populations and during the life cycle

Annals of Human Biology ◽

10.1080/03014460701367942 ◽

2007 ◽

Vol 34 (3) ◽

pp. 377-392 ◽

Cited By ~ 6

Author(s):

Elisabetta Marini ◽

Stefano Cabras ◽

Esther Rebato ◽

Roberto Buffa ◽

Itziar Salces ◽

...

Keyword(s):

Sex Differences ◽

Life Cycle ◽

Human Populations

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MicroCT protocols for scanning of embryos and juvenile Hexaplex trunculus v1

10.17504/protocols.io.bxw4ppgw ◽

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.

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