Orthodontic Management of a Mandibular Double-tooth Incisor: A Case Report

The presence of a double-tooth requires specific complex management due to the need for differential diagnosis and following treatment choices. The aim of this report was to present a rare case of a geminated mandibular lateral incisor, treated with an orthodontic approach. A Caucasian 10.9-year-old girl presented a lower right double-tooth incisor, with a class 1 molar and a class 2 cuspid tendency on both sides. The upper arch was constricted as shown by bilaterally tendencies to cross-bite, a slightly lower midline deviation was reported and a lack of space for all four permanent cuspids was confirmed also by the panoramic X-ray. In the lower arch, there was a severe crowding of about 14 mm and a buccally ectopic left canine. Overbite was normal and Overjet minimally increased. The double-tooth was identified like a geminated tooth, for the presence of one root and one pulp canal of increased size, as shown by the radiographic examinations. The anomalous tooth was managed with an orthodontic approach associated with a progressive stripping to reshape the crown. A two-phase treatment plan was performed, based on first maxillary expansion and lip bumper and then fixed appliances, in order to achieve a proper occlusion and a better aesthetic.

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Long-Term Outcomes of Nonextraction Treatment in a Patient with Severe Mandibular Crowding

Case Reports in Dentistry ◽

10.1155/2020/1376472 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Vincenzo Grassia ◽

Ludovica Nucci ◽

Paola Martina Marra ◽

Gaetano Isola ◽

Angelo Itro ◽

...

Keyword(s):

Class I ◽

Term Outcome ◽

Long Term Outcome ◽

Deep Bite ◽

Long Term Follow Up ◽

Fixed Appliances ◽

Lip Bumper ◽

Lower Arch

Objective. To describe a clinical case with a severe mandibular crowding treated without extraction and showing a long-term outcome. Methods. A 14-year-old boy in permanent dentition showed a class I molar and cuspid relationship, a severe deep bite of 8 mm, a constricted V-shaped upper arch with moderate crowding, and a severe crowding of about 12 mm in the lower arch. The panoramic X-ray showed an impacted upper right canine. The treatment started with the placement of a transpalatal bar and 0.022×0.028 in standard edgewise appliances in the upper arch and a lip bumper bonded on the second lower molars. Initial leveling of the teeth was accomplished with light Australian round wires. Finishing was then performed with rectangular wires. The phase with fixed appliances lasted 2 years and 9 months, and the patient was motivated and cooperative throughout the treatment, although with poor oral hygiene. The patient was treated without extractions. Results. The space was gained with the first and second upper molar derotations using the transpalatal bar and the gingival lip bumper in the lower arch. The upper right canine was well positioned, and the maxillary arch form was improved. The severe lower crowding was completely corrected, and a good overbite was achieved. Conclusion. A conservative, nonextraction treatment approach for this patient with class I malocclusion with severe mandibular crowding was effective, and the results have remained stable after a long-term follow-up (10 years).

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Identification of Pulmonary Deposits from a Sandpaper Worker: A Study by Electron Microscopy and X-Ray Microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053061 ◽

1982 ◽

Vol 40 ◽

pp. 52-53

Author(s):

S. K. Peng ◽

M.A. Egy ◽

J. K. Singh ◽

M.B. Bishop

Keyword(s):

Electron Microscopy ◽

Environmental Pollution ◽

Rare Case ◽

Interstitial Fibrosis ◽

X Ray ◽

Documented Case ◽

Etiologic Agents ◽

Pulmonary Interstitial Fibrosis ◽

Gold Miners ◽

Pulmonary Changes

Electron microscopy and energy dispersive x-ray microanalysis (EDXA) are found to be very useful tools for identification of etiologic agents in pneumoconiosis or interstitial pulmonary disorders. Pulmonary interstitial fibrosis and granulomatosis are frequently associated with occupational and environmental pollution. Numerous reports of pneumoconiosis in various occupations such as coal and gold miners are presented in the literature. However, there is no known documented case of pulmonary changes in workers in the sandpaper industry. This study reports a rare case of pulmonary granulomatosis containing deposits from abrasives of sandpaper diagnosed by using EDXA.

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Small angle X-ray scattering study of porosity variation in a styrene-divinylbenzene copolymer

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19811675 ◽

1981 ◽

Vol 46 (7) ◽

pp. 1675-1681 ◽

Cited By ~ 13

Author(s):

Josef Baldrian ◽

Božena N. Kolarz ◽

Henrik Galina

Keyword(s):

Small Angle ◽

Structural Parameters ◽

Two Phase ◽

X Ray ◽

Porosity Variation ◽

Swelling Agent ◽

X Ray Scattering ◽

Styrene Divinylbenzene ◽

Ray Scattering

Porosity variations induced by swelling agent exchange were studied in a styrene-divinylbenzene copolymer. Standard methods were used in the characterization of copolymer porosity in the dry state and the results were compared with related structural parameters derived from small angle X-ray scattering (SAXS) measurements as developed for the characterization of two-phase systems. The SAXS method was also used for porosity determination in swollen samples. The differences in the porosity of dry samples were found to be an effect of the drying process, while in the swollen state the sample swells and deswells isotropically.

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The British Orthodontic Society MOrth Cases Prize 2019

Journal of Orthodontics ◽

10.1177/1465312520982876 ◽

2021 ◽

pp. 146531252098287

Author(s):

Adam C Jowett

Keyword(s):

Class Ii ◽

Functional Appliance ◽

First Case ◽

Permanent Molars ◽

Fixed Appliances ◽

Unerupted Teeth ◽

Removable Appliance ◽

Division 2 ◽

Lower Arch ◽

First Permanent Molars

This paper describes the orthodontic treatment of two cases that were successful in winning the British Orthodontic Society (BOS) Membership in Orthodontics (MOrth) Cases Prize in 2019. The first case describes the management of a 12-year-old girl with a Class II division 2 malocclusion complicated by moderate upper and lower arch crowding, multiple unerupted teeth, restored lower first permanent molars, pseudo-transposition of the lower left lateral incisor and canine, and diminutive upper lateral incisors. Treatment involved a combination of an upper removable appliance followed by upper and lower preadjusted edgewise fixed appliances. Anteroposterior correction and overbite reduction was achieved with triangular Class II elastics with posterior occlusal disengagement. Both upper permanent canines were exposed and aligned, and the diminutive upper incisors built up with resin-based composite. Treatment was completed over a period of 23 months. The second case describes the management of a 13-year-old boy with a Class II division 2 malocclusion complicated by severe upper and lower arch crowding with unerupted UR5, UL4, LR3, rotated LR5, an increased overbite complete to tooth, buccally displaced upper canines and hypoplastic upper first premolars. Treatment involved a first phase of functional appliance therapy, followed by the extraction of UR4, UL4, LL5, LR4 and upper and lower preadjusted edgewise fixed appliances over a 28-month period.

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Revisiting the Bøggild Intergrowth in Iridescent Labradorite Feldspars: Ordering, Kinetics, and Phase Equilibria

Minerals ◽

10.3390/min11070727 ◽

2021 ◽

Vol 11 (7) ◽

pp. 727

Author(s):

Shiyun Jin ◽

Huifang Xu ◽

Seungyeol Lee

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Atom Probe ◽

Phase Region ◽

Two Phase ◽

Subsolidus Phase ◽

Plagioclase Feldspar ◽

X Ray ◽

Transmission Electron ◽

Scanning Transmission

The enigmatic Bøggild intergrowth in iridescent labradorite crystals was revisited in light of recent work on the incommensurately modulated structures in the intermediated plagioclase. Five igneous samples and one metamorphic labradorite sample with various compositions and lamellar thicknesses were studied in this paper. The lamellar textures were characterized with conventional transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM). The compositions of individual lamellae were analyzed with high-resolution energy-dispersive X-ray spectroscopy (EDS) mapping and atom probe tomography (APT). The average structure states of the studied samples were also compared with single-crystal X-ray diffraction data (SC-XRD). The Na-rich lamellae have a composition of An44–48, and the Ca-rich lamellae range from An56 to An63. Significant differences between the lamellar compositions of different samples were observed. The compositions of the Bøggild intergrowth do not only depend on the bulk compositions, but also on the thermal history of the host rock. The implications on the subsolidus phase relationships of the plagioclase feldspar solid solution are discussed. The results cannot be explained by a regular symmetrical solvus such as the Bøggild gap, but they support an inclined two-phase region that closes at low temperature.

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XCOVNet: Chest X-ray Image Classification for COVID-19 Early Detection Using Convolutional Neural Networks

New Generation Computing ◽

10.1007/s00354-021-00121-7 ◽

2021 ◽

Author(s):

Vishu Madaan ◽

Aditya Roy ◽

Charu Gupta ◽

Prateek Agrawal ◽

Anand Sharma ◽

...

Keyword(s):

Image Classification ◽

Second Phase ◽

Two Phase ◽

X Ray ◽

The Neural Network ◽

Rapid Spread ◽

Chest X Ray ◽

Polymerase Chain ◽

Two Phases ◽

Active Patients

AbstractCOVID-19 (also known as SARS-COV-2) pandemic has spread in the entire world. It is a contagious disease that easily spreads from one person in direct contact to another, classified by experts in five categories: asymptomatic, mild, moderate, severe, and critical. Already more than 66 million people got infected worldwide with more than 22 million active patients as of 5 December 2020 and the rate is accelerating. More than 1.5 million patients (approximately 2.5% of total reported cases) across the world lost their life. In many places, the COVID-19 detection takes place through reverse transcription polymerase chain reaction (RT-PCR) tests which may take longer than 48 h. This is one major reason of its severity and rapid spread. We propose in this paper a two-phase X-ray image classification called XCOVNet for early COVID-19 detection using convolutional neural Networks model. XCOVNet detects COVID-19 infections in chest X-ray patient images in two phases. The first phase pre-processes a dataset of 392 chest X-ray images of which half are COVID-19 positive and half are negative. The second phase trains and tunes the neural network model to achieve a 98.44% accuracy in patient classification.

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Enamel interproximal reduction during treatment with clear aligners: digital planning versus OrthoCAD analysis

BMC Oral Health ◽

10.1186/s12903-021-01487-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Giuseppina Laganà ◽

Arianna Malara ◽

Roberta Lione ◽

Carlotta Danesi ◽

Simonetta Meuli ◽

...

Keyword(s):

Treatment Plan ◽

End Of Treatment ◽

The Mean ◽

The Difference ◽

Dependent Sample ◽

University Of Rome ◽

The University ◽

Enamel Reduction ◽

Lower Arch

Abstract Background The aim of the study was to compare the amount of interproximal enamel reduction (IPR) provided on ClinCheck software with the amount of IPR carried out by the orthodontist during treatment with clear aligners. Methods 30 subjects (14 males, 16 females; mean age of 24.53 ± 13.41 years) randomly recruited from the Invisalign account of the Department of Orthodontics at the University of Rome “Tor Vergata” from November 2018 to October 2019, were collected according to the following inclusion criteria: mild to moderate dento-alveolar discrepancy (1.5–6.5 mm); Class I canine and molar relationship; full permanent dentition (excluding third molars); both arches treated only using Comprehensive Package by Invisalign system; treatment plan including IPR. Pre- (T0) and post-treatment (T1) digital models (.stl files), created from an iTero scan, were collected from all selected patients. The OrthoCAD digital software was used to measure tooth mesiodistal width in upper and lower arches before (T0) and at the end of treatment (T1) before any refinement. The widest mesio-distal diameter was measured for each tooth excluding molars by “Diagnostic” OrthoCAD tool. The total amount of IPR performed during treatment was obtained comparing the sum of mesio-distal widths of all measured teeth at T0 and T1. Significant T1–T0 differences were tested with dependent sample t-test (P < 0.05). Results In the upper arch, IPR was digitally planned on average for 0.62 mm while in the lower arch was on average for 1.92 mm. As for the amount of enamel actually removed after IPR performing, it was on average 0.62 mm in the maxillary arch. In the mandibular arch, the mean of IPR carried out was 1.93 mm. The difference between planned IPR and performed IPR is described: this difference was on average 0.00 mm in the upper arch and 0.01 in the lower arch. Conclusions The amount of enamel removed in vivo corresponded with the amount of IPR planned by the Orthodontist using ClinCheck software.

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Nanostructured TiO2-Based Composites for Light Absorption

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.975.207 ◽

2014 ◽

Vol 975 ◽

pp. 207-212

Author(s):

Dayse I. dos Santos ◽

Olayr Modesto Jr. ◽

Luis Vicente A. Scalvi ◽

Americo S. Tabata

Keyword(s):

Metal Oxide ◽

Light Absorption ◽

Structural Characteristics ◽

Sol Gel ◽

Second Phase ◽

X Ray Diffraction ◽

Two Phase ◽

X Ray ◽

Oxide Powders

Metal oxide nanocomposites were prepared by two different routes: polyol and sol-gel. Characterization by X ray diffraction showed that the first process produces directly a two-phase material, while the sol-gel powder never showed second phase below 600°C. Light spectroscopy of the treated powders indicated similarities for the processed materials. Although the overall material compositions are about the same, different structural characteristics are found for each processing. With the exception of Ti-Zn materials, all the double metal oxide powders showed higher absorbance than either TiO2 powder.

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Imaging and Resistivity Studies of Saturation Gradients in Two-Phase Flow in 3-D Porous Media

MRS Proceedings ◽

10.1557/proc-464-371 ◽

1996 ◽

Vol 464 ◽

Cited By ~ 1

Author(s):

E. H. Kawamoto ◽

Po-Zen Wong

Keyword(s):

Computed Tomography ◽

Porous Media ◽

Two Phase Flow ◽

Water Saturation ◽

Glass Beads ◽

Water Phase ◽

Phase Flow ◽

Two Phase ◽

Vertical Column ◽

X Ray

ABSTRACTWe have carried out x-ray radiography and computed tomography (CT) to study two-phase flow in 3-D porous media. Air-brine displacement was imaged for drainage and imbibition experiments in a vertical column of glass beads. By correlating water saturation Sw with resistance R, we find that there is a threshold saturation S* ≈ 0.2, above which R(SW) ∼ Sw−2, in agreement with the empirical Archie relation. This holds true for both drainage and imbibition with littlehysteresis, provided that Sw remains above S*. Should Sw drop below S* during drainage, R(Sw) rises above the Archie prediction, exhibiting strong hysteresis upon reimbibition. This behavior suggests a transition in the connectivity of the water phase near S*, possibly due to percolation effects.

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