The effect of 12 weeks of mechanical vibration on root resorption: a micro-CT study

Abstract Objective The aim was to investigate the effect of mechanical vibration on root resorption with or without orthodontic force application. Material and methods Twenty patients who required maxillary premolar extractions as part of orthodontic treatment were randomly divided into two groups of 10: no-force group and force group. Using a split-mouth procedure, each patient’s maxillary first premolar teeth were randomly assigned as either vibration or control side for both groups. A buccally directed vibration of 50 Hz, with an Oral-B HummingBird device, was applied to the maxillary first premolar for 10 min/day for 12 weeks. After the force application period, the maxillary first premolars were extracted and scanned with micro-computed tomography. Fiji (ImageJ), performing slice-by-slice quantitative volumetric measurements, was used for resorption crater calculation. Total crater volumes were compared with the Wilcoxon and Mann–Whitney U tests. Results The total crater volumes in the force and no-force groups were 0.476 mm3 and 0.017 mm3 on the vibration side and 0.462 mm3 and 0.031 mm3 on the control side, respectively. There was no statistical difference between the vibration and control sides (P > 0.05). There was more resorption by volume in the force group when compared to the no-force group (P < 0.05). Conclusion Mechanical vibration did not have a beneficial effect on reducing root resorption; however, force application caused significant root resorption.

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Using micro-computed tomography to examine the larynx in cases of suspected strangulation—a comparison of case findings and control images

International Journal of Legal Medicine ◽

10.1007/s00414-019-02194-y ◽

2019 ◽

Vol 134 (4) ◽

pp. 1441-1450 ◽

Cited By ~ 1

Author(s):

Waltraud Baier ◽

Brian A. Burnett ◽

Mark Payne ◽

Jason M. Warnett ◽

Mark A. Williams

Keyword(s):

Computed Tomography ◽

Spatial Resolution ◽

Forensic Pathology ◽

Causes Of Death ◽

Imaging Technique ◽

Micro Ct ◽

Donor Group ◽

Micro Computed Tomography ◽

Naturally Occurring ◽

And Control

Abstract The examination of strangulation is one of the most challenging causes of death diagnoses encountered in forensic pathology. The injuries are often subtle and difficult to detect, especially in cases that lack superficial marks. Fractures of the laryngeal skeleton are commonly regarded as evidence of strangulation but these can be too subtle to be detected during autopsy. Micro-CT is a novel imaging technique that achieves a spatial resolution 1 μm or less which lends itself to the examination of small and delicate structures such as the larynx. However, there is little information to date regarding the appearance of the larynx at this scale, thus complicating the interpretation of the micro-CT images. This study therefore uses micro-CT to examine ten larynges from strangulation deaths and to compare them to nineteen samples from donor individuals in order to distinguish between naturally occurring features and actual trauma. It was found that there are several features which mimic damage in the donor group. Using associated case information, initial trends and patterns of different strangulation methods were established.

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Contribution of cone beam computed tomography to the detection of apical root resorption after orthodontic treatment in root-filled and vital teeth

The Angle Orthodontist ◽

10.2319/042814-308.1 ◽

2014 ◽

Vol 85 (5) ◽

pp. 771-776 ◽

Cited By ~ 6

Author(s):

Iury Castro ◽

José Valladares-Neto ◽

Carlos Estrela

Keyword(s):

Computed Tomography ◽

Cone Beam Computed Tomography ◽

Orthodontic Treatment ◽

Statistical Difference ◽

Root Resorption ◽

Cone Beam ◽

Apical Root Resorption ◽

Before And After ◽

History Of ◽

Mean Differences

ABSTRACT Objective: To investigate whether root-filled teeth are similar to vital pulp teeth in terms of apical root resorption (ARR) after orthodontic treatment. Materials and Methods: An original sample of cone beam computed tomography (CBCT) images of 1256 roots from 30 orthodontic patients were analyzed. The inclusion criteria demanded root-filled teeth and their contralateral vital teeth, while teeth with history of trauma had to be excluded to comply with exclusion criteria. CBCT images of root-filled teeth were compared before and after orthodontic treatment in a split-mouth design study. Tooth measurements were made with multiplanar reconstruction using axial-guided navigation. The statistical difference between the treatment effects was compared using the paired t-test. Results: Twenty posterior root-filled teeth and their contralaterals with vital pulp were selected before orthodontic treatment from six adolescents (two boys and four girls; mean [SD] age 12.8 [1.8] years). No differences were detected between filled and vital root lengths before treatment (P = .4364). The mean differences in root length between preorthodontic and postorthodontic treatment in filled- and vital roots were −0.30 mm and −0.16 mm, respectively, without any statistical difference (P = .4197) between them. Conclusion: There appears to be no increase in ARR after orthodontic treatment in root-filled teeth with no earlier ARR.

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Does the rhythm and appliance type of rapid maxillary expansion have an effect on root resorption?: A comparative clinical study using micro–computed tomography

The Angle Orthodontist ◽

10.2319/052220-465.1 ◽

2021 ◽

Author(s):

Sıddık Malkoç ◽

Rukiye Alçin ◽

Aslıhan Uzel

Keyword(s):

Computed Tomography ◽

Root Resorption ◽

Rapid Maxillary Expansion ◽

Micro Ct ◽

Micro Computed Tomography ◽

Maxillary Expansion ◽

3D Images ◽

Retention Period ◽

Root Sample ◽

Comparative Clinical Study

ABSTRACT Objectives To evaluate the volume, amount, and localization of root resorption in the upper first premolars by micro–computed tomography (micro-CT) after three different rapid maxillary expansion appliances and two different activation rhythms. Materials and Methods The patients were divided into three groups; Hyrax, acrylic cap splint (ACS), and full coverage acrylic bonded (FCAB) appliances. Each group was then divided into the following two subgroups: rapid maxillary expansion (RME) and semirapid maxillary expansion (SRME). After expansion was completed, the appliances were stabilized for 12 weeks during the retention period. For each group, 10 premolars (for a total of 60 premolars) were scanned with the micro-CT (SkyScan). The reconstructed 3D images of each root sample were divided into six regions. The resorption craters on these six different root surfaces were analyzed by special CTAn (SkyScan) software for direct volumetric measurements. Kruskal-Wallis one-way analysis of variance and Mann-Whitney U tests were used for statistical analysis. Results The total volume of root resorption was less with FCAB than with ACS and Hyrax (P < .001). In all groups, a greater volume of resorption was found on the buccal surface than on the lingual surface (P < .001). No significant differences were found between the RME and SRME groups (P > .05). Conclusions All expansion appliances caused root resorption in the upper first premolar teeth, but FCAB may be safer in terms of root resorption. The resorption craters were generally concentrated on the buccal surface. There was no effect of activation rhythm on root resorption.

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Analysis of Orthodontically Induced Root Resorption Using Micro-Computed Tomography (Micro-CT)

The Angle Orthodontist ◽

10.2319/112107-546.1 ◽

2009 ◽

Vol 79 (1) ◽

pp. 91-96 ◽

Cited By ~ 18

Author(s):

Tom Wierzbicki ◽

Tarek El-Bialy ◽

Saleh Aldaghreer ◽

Guang Li ◽

Michael Doschak

Keyword(s):

Computed Tomography ◽

Orthodontic Treatment ◽

Root Resorption ◽

Treatment Plan ◽

Tooth Root ◽

Micro Computed Tomography ◽

Volume Number ◽

Healthy Adolescent ◽

Scanned Images ◽

Plan Modification

Abstract Objective: To establish a protocol for assessing orthodontically induced tooth root resorption (OITRR) in human premolars using micro-computed tomography. Materials and Methods: Ten extracted maxillary first premolars were obtained from eight healthy adolescent patients; five of these premolars were extracted before any orthodontic movement was applied to them, and the other five premolars were involved in nonextraction orthodontic treatment for 1 year before treatment plan modification lead to extraction treatment. Using reconstructed scanned images, we measured several key resorption lacunae parameters, including the number, volume, and depth on each surface, as well as its extension coronoapically. Results: Orthodontic treatment resulted in a significantly greater tooth root resorption lacunae volume, number, maximum depth, and coronoapical extension as well as in areas of dentin demineralization subjacent to the resorption lacunae than in normal premolars. Conclusions: We have established a protocol to evaluate OITRR quantitatively and have provided a method to predict further resorption based on dentine demineralization.

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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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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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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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Micro-Computed Tomography (Micro-CT) Evaluation of Effects of Different Rotary Glide Path Techniques on Canal Transportation and Centering in Curved Root Canals

Medical Science Monitor ◽

10.12659/msm.916112 ◽

2019 ◽

Vol 25 ◽

pp. 6351-6358

Author(s):

Gabrielė Česaitienė ◽

Tadas Venskutonis ◽

Vita Mačiulskienė ◽

Vaidotas Cicėnas ◽

Vykintas Samaitis ◽

...

Keyword(s):

Computed Tomography ◽

Micro Ct ◽

Micro Computed Tomography ◽

Root Canals ◽

Glide Path ◽

Ct Evaluation ◽

Canal Transportation ◽

Curved Root Canals

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Quantitative micro-computed tomography analysis and rheological investigation of Nitrile rubber/Rockwool composites

Journal of Composite Materials ◽

10.1177/00219983211033886 ◽

2021 ◽

pp. 002199832110338

Author(s):

Elisson BD da Rocha ◽

Ana Maria F de Sousa ◽

Ana Lúcia N da Silva ◽

Cristina RG Furtado ◽

Marcos V Colaço ◽

...

Keyword(s):

Computed Tomography ◽

Elastic Modulus ◽

Aspect Ratio ◽

Volume Fraction ◽

Nitrile Rubber ◽

Micro Ct ◽

Micro Computed Tomography ◽

Rubber Composites ◽

Ratio Data ◽

Ct Analysis

This study reports the reinforcement degree investigation of two types of rockwool fibers (F1 and F2), in nitrile rubber composites. The micro-computed tomography (micro-CT) 3D images showed that both fibers were well-dispersed in the NBR matrix, without a preferential orientation. The micro-CT analysis also allowed quantifying volume fraction, inter-fiber distance, and aspect ratio. Those morphometric parameters were used for supporting the composites rheological behavior assessment. Changes in the elastic modulus and phase angle followed the same trend of the inter-fiber distance values, regardless the type of fiber. Both volume fraction and aspect ratio data from the micro-CT analysis were used to predict theoretical values of elastic modulus using the Guth-Gold and modified Guth-Gold equations, and the results obtained were compared to the rheological experimental data. This analysis was helpful to better understand the rockwool fibers reinforcement degree differences in the production of the nitrile rubber composites.

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Effect of fluoride on root resorption following heavy and light orthodontic force application for 4 weeks and 12 weeks of retention

The Angle Orthodontist ◽

10.2319/072512-606.1 ◽

2012 ◽

Vol 83 (3) ◽

pp. 418-424 ◽

Cited By ~ 3

Author(s):

Ersan I. Karadeniz ◽

Carmen Gonzales ◽

Tamer Turk ◽

Devrim Isci ◽

Aynur M. Sahin-Saglam ◽

...

Keyword(s):

Null Hypothesis ◽

Root Resorption ◽

Positive Control ◽

Orthodontic Force ◽

Control Side ◽

Force Application ◽

Fluoride Intake ◽

High Fluoride ◽

Experimental Side ◽

Light Force

ABSTRACT Objective: To evaluate the null hypothesis that fluoride intake via drinking water has no effect on orthodontic root resorption in humans after orthodontic force application for 4 weeks and 12 weeks of retention. Materials and Methods: Forty-eight patients who required maxillary premolar extractions as part of their orthodontic treatment were selected from two cities in Turkey. These cities had a high and low fluoride concentration in public water of ≥2 pm and ≤0.05 pm, respectively. The patients were randomly separated into four groups of 12 each: group 1HH, high fluoride (≥2 ppm) and heavy force (225 g); group 2LH, low fluoride (≤0.05 ppm) and heavy force; group 3HL, high fluoride and light force (25 g); and group 4LL, low fluoride and light force. Light or heavy buccal tipping force was applied on the upper first premolars for 28 days. At day 28, the left premolars were extracted (positive control side); the right premolars (experimental side) were extracted after 12 weeks of retention. The samples were analyzed with microcomputed tomography. Results: On the positive control side, under heavy force application, the high fluoride groups exhibited less root resorption (P = .015). On the experimental side, it was found that fluoride reduced the total volume of root resorption craters; however, this effect was not statistically significant (P = .237). Moreover, the results revealed that under heavy force application experimental teeth exhibited more root resorption than positive control groups. Conclusion: The null hypothesis could not be rejected. High fluoride intake from public water did not have a beneficial effect on the severity of root resorption after a 4-week orthodontic force application and 12 weeks of passive retention.

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