scholarly journals Morphometric evaluation of the slot of aesthetic orthodontic brackets.

2021 ◽  
Vol 10 (3) ◽  
pp. 1-10
Author(s):  
Jorge Maza-Sánchez ◽  
◽  
Víctor Marcel Aguilar-Salas ◽  
Keyword(s):  
Three Dimensional ◽  
Public Health Problem ◽  
Tolerance Range ◽  
Dimensional Control ◽  
Polycrystalline Ceramic ◽  
Ceramic Brackets ◽  
Student’S T ◽  
Distal Direction ◽  
Morphometric Evaluation ◽  
Dental Malocclusion

Introduction: : Dental malocclusion is a public health problem and orthodontics is the specialty in charge of diagnosing and treating it, aesthetic brackets are an alternative, the costs are varied, which makes its precision doubtful. Objective: Evaluate the measurement and geometry of the slot of three brands of aesthetic brackets and verify their precision. Material and Methods: Twenty-four aesthetic Roth prescription 0.022” slot polycrystalline ceramic brackets were evaluated in three brands: American Orthodontics (United States), Morelli (Brazil) and Class One (China). Eight samples were measured per group in a specialized laboratory certified in measurement and calibration, the measurements of internal and external height were verified, per mesial and distal; and the parallelism of the slot of each bracket. The results were processed with SPSS 22 and tests of variance (ANOVA), Tukey and Student's t were used. Results: The measurements of the brackets' grooves do not correspond to the measurements announced by the manufacturers, these are greater, however, American Orthodontics is within the tolerance range (p<0.01); the slots in the mesio-distal direction and the lingual vestibule are not parallel in Morelli and Class One. Conclusion: The results of this study indicate that the slots of the supports are oversized, their geometry is not precise and varies greatly between brands and prices. The three-dimensional control of the tooth could be compromised.

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

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.

scholarly journals Vital effects in coral skeletal composition display strict three‐dimensional control

2006 ◽  
Vol 33 (11) ◽  
Author(s):  
Anders Meibom ◽  
Hiyayoshi Yurimoto ◽  
Jean‐Pierre Cuif ◽  
Isabelle Domart‐Coulon ◽  
Fanny Houlbreque ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Dimensional Control ◽  
Vital Effects

scholarly journals Enamel loss following ceramic bracket debonding: A quantitative analysis in vitro

2014 ◽  
Vol 85 (4) ◽  
pp. 651-656 ◽  
Author(s):  
Sam N. Suliman ◽  
Terry M. Trojan ◽  
Daranee Tantbirojn ◽  
Antheunis Versluis
Keyword(s):  
Standard Deviation ◽  
Three Dimensions ◽  
Optical Scanner ◽  
Polycrystalline Ceramic ◽  
Tooth Surfaces ◽  
Ceramic Brackets ◽  
Successful Removal ◽  
Ceramic Bracket ◽  
Surface Changes

ABSTRACT Objective:  To measure enamel surface changes after ceramic bracket debonding and after cleanup. Materials and Methods:  Forty extracted teeth were scanned in three dimensions using an optical scanner (baseline). Two ceramic bracket systems were placed (19 metal-reinforced polycrystalline ceramic brackets; 21 monocrystalline ceramic brackets). Seven days later, brackets were debonded and teeth scanned (post-debond). Adhesive remnants and bracket fragments were recorded. Tooth surfaces were cleaned using a finishing carbide bur and scanned again (post-cleanup). Post-debond and post-cleanup scans were aligned with the baseline, and surface changes were quantified. Results were statistically compared using t-tests and Mann-Whitney tests (α  =  .05). Results:  The depth of enamel loss (mean ± standard deviation) post-debond was 21 ± 8 µm and 33 µm and post-cleanup was 28 ± 14 µm and 18 ± 8 µm (P  =  .0191); the post-debond remnant thickness was 188 ± 113 µm and 120 ± 37 µm (P  =  .2381) and post-cleanup was 16 ± 5 µm and 15 µm for polycrystalline and monocrystalline ceramic brackets, respectively. The monocrystalline ceramic brackets predominantly left all adhesive on the tooth; the polycrystalline ceramic brackets were more likely to leave bracket fragments attached. Conclusion:  Both systems allowed successful removal of the brackets with minimal enamel loss. However, the polycrystalline ceramic brackets left more fragments on the tooth, which complicated cleanup efforts.

A Study of Frictional Forces between Orthodontic Brackets and Archwires

1994 ◽  
Vol 21 (4) ◽  
pp. 349-357 ◽  
Author(s):  
Alison Downing ◽  
John McCabe ◽  
Peter Gordon
Keyword(s):  
Stainless Steel ◽  
Frictional Force ◽  
Nickel Titanium ◽  
The Other ◽  
Friction Testing ◽  
Beta Titanium ◽  
Polycrystalline Ceramic ◽  
Ceramic Brackets ◽  
Frictional Forces ◽  
Testing Assembly

The differences in magnitude of static and kinetic frictional forces generated by 0·022 × 0·030-inch stainless steel (Dentaurum®) and polycrystalline ceramic (Transcend®) brackets in combinntion with archwires of different sizes (0·018 inch and 0·019 × 0·025 inch) and materials (stainless steel, nickel-titanium, and beta-titanium) at a constant ligature force were investigated. A friction-testing assembly using the Instron machine was used. In all cases, the static frictional force was greater than the kinetic frictional force. There were no significant differences in the frictional forces generated by stainless steel and polycrystalline ceramic brackets. Beta-titanium archwires produced greater frictinal forces than the other two materials. Increasing the archwire diameter increased the frictional force.

The effectiveness of miniscrews in the three-dimensional control of a palatal impacted canine: “Canine Only” approach Cani Caniene

2021 ◽  
Author(s):  
Fabio Annarumma ◽  
Martina D’Emidio ◽  
Giuseppe Rodi ◽  
Gianni Battista ◽  
Giulia Papi ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Dimensional Control ◽  
Impacted Canine

scholarly journals Three-Dimensional Evaluation of Slow Maxillary Expansion with Leaf Expander vs. Rapid Maxillary Expansion in a Sample of Growing Patients: Direct Effects on Maxillary Arch and Spontaneous Mandibular Response

2020 ◽  
Vol 10 (13) ◽  
pp. 4512
Author(s):  
Gianguido Cossellu ◽  
Alessandro Ugolini ◽  
Matteo Beretta ◽  
Marco Farronato ◽  
Alessandro Gianolio ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Test Group ◽  
Maxillary Expansion ◽  
Second Molar ◽  
Mandibular Arch ◽  
Posterior Crossbite ◽  
Student’S T ◽  
Maxilla And Mandible ◽  
Maxillary Deficiency ◽  
Student’S T Test

The aim is to evaluate the effects of slow maxillary expansion on maxillary and mandibular arch, using a slow maxillary expander (SME-Leaf Expander) banded on primary second molar. Ninety patients with transverse maxillary deficiency and posterior crossbite were selected. Sixty-nine patients (33 males/36 females; 7.6 ± 1.7 years old) who underwent SME and 21 patients (10 males/11 females; 7.4 ± 1.2 years old) who were treated with rapid maxillary expander (RME). Digital models obtained pre- and post-treatment at appliance removal (9 to 11 months) were processed by means of a 3D scanner (Trios 3, 3Shape D250 laser, Copenhagen, Denmark). Interdental width in both maxilla and mandible were measured with 3 SHAPE Ortho Analyzer. Four Maxillary and four mandibular interdental width were traced and evaluated. The adequate Student’s t-test (dependent or independent) was used to compare intra and intergroups interdental width differences (p < 0.05). The efficacy of the SME was confirmed both on maxillary and mandibular arch. All the maxillary and mandibular interdental widths increased significantly (p < 0.001). The comparison with the RME group showed significant statistical differences between the two treatments with a greater increase in primary first and second intermolar and canine width for the test group (p < 0.001). SME with Leaf Expander produced statistically significant effects for the correction of transverse maxillary deficiencies with a significant indirect effect on the mandibular arch.

scholarly journals Additively manufactured heterogeneous substrates for three‐dimensional control of local permittivity

2014 ◽  
Vol 50 (10) ◽  
pp. 745-746 ◽  
Author(s):  
J. Tribe ◽  
W.G. Whittow ◽  
R.W. Kay ◽  
J.C. Vardaxoglou
Keyword(s):  
Three Dimensional ◽  
Dimensional Control

scholarly journals An Alternate Method to Springback Compensation for Sheet Metal Forming

2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Waluyo Adi Siswanto ◽  
Agus Dwi Anggono ◽  
Badrul Omar ◽  
Kamaruzaman Jusoff
Keyword(s):  
Hybrid Method ◽  
Sheet Metal Forming ◽  
Metal Forming ◽  
Three Dimensional ◽  
Numerical Approach ◽  
Tolerance Range ◽  
Compensation Process ◽  
Dimensional Deviation ◽  
Three Dimensional Models ◽  
Cold Stamping

The aim of this work is to improve the accuracy of cold stamping product by accommodating springback. This is a numerical approach to improve the accuracy of springback analysis and die compensation process combining the displacement adjustment (DA) method and the spring forward (SF) algorithm. This alternate hybrid method (HM) is conducted by firstly employing DA method followed by the SF method instead of either DA or SF method individually. The springback shape and the target part are used to optimize the die surfaces compensating springback. The hybrid method (HM) algorithm has been coded in Fortran and tested in two- and three-dimensional models. By implementing the HM, the springback error can be decreased and the dimensional deviation falls in the predefined tolerance range.

scholarly journals Emerging Terbinafine Resistance in Trichophyton: Clinical Characteristics, Squalene Epoxidase Gene Mutations, and a Reliable EUCAST Method for Detection

2019 ◽  
Vol 63 (10) ◽  
Author(s):  
Ditte M. L. Saunte ◽  
Rasmus K. Hare ◽  
Karin M. Jørgensen ◽  
René Jørgensen ◽  
Mette Deleuran ◽  
...  
Keyword(s):  
Homology Modeling ◽  
Susceptibility Testing ◽  
Topical Therapy ◽  
Antifungal Susceptibility ◽  
Acquired Resistance ◽  
Three Dimensional ◽  
Public Health Problem ◽  
Squalene Epoxidase ◽  
Content Type ◽  
The Mean

ABSTRACT In recent years, cases involving terbinafine-resistant Trichophyton isolates have been reported increasingly, particularly in India. We present 14 cases of terbinafine treatment failure in Trichophyton-infected Danish patients due to acquired resistance. Patients infected with Trichophyton rubrum (n = 12) or Trichophyton interdigitale (n = 2) with elevated terbinafine MICs during 2013–2018 were included. Antifungal susceptibility testing (AFST) was performed following a modified EUCAST E.Def 9.3.1 method (5 days of incubation) with or without cycloheximide and chloramphenicol (CC) supplementation of the growth medium. The squalene epoxidase (SE) target gene was sequenced, and 3-dimensional enzyme homology modeling was performed. Most patients (12/14 [86%]) were male. The mean age was 53.5 years (range, 11 to 77 years). The mean duration of infections was 4.8 years at the time of resistance detection. Prior systemic terbinafine treatment was documented for all patients, and topical therapy for 62% (information was missing in one case). Overall, nine isolates (64%) displayed high terbinafine resistance (MICs, 4 to >8 mg/liter), while two (14%) displayed moderate (MICs, 1 to 2 mg/liter) and three (21%) displayed low (MICs, 0.125 to 0.25 mg/liter) terbinafine resistance compared with control isolates. MICs generated with or without CC supplementation were similar, but CC prevented contamination. Known and novel SE amino acid substitutions (F397L, L393F, L393S, F415S, H440Y F484Y, and I121M V237I) were detected in resistant but not control isolates. Three-dimensional homology modeling suggested a role of the novel I121M and V237I alterations. Terbinafine resistance has been detected in Denmark using a modified EUCAST method, which facilitated susceptibility testing of dermatophytes. Action is needed for this emerging public health problem.

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