scholarly journals Transfer accuracy of four different lingual retainer transfer methods using digital orthodontic models: An in vivo comparative study

2021 ◽  
Author(s):  
Yasemin Nur Korkmaz ◽  
Semiha Arslan
Keyword(s):  
Orthodontic Treatment ◽  
Three Dimensional ◽  
Acrylic Resin ◽  
Digital Models ◽  
Indirect Bonding ◽  
Angular Measurements ◽  
Clinical Accuracy ◽  
Lingual Retainer ◽  
Transfer Accuracy

ABSTRACT Objectives To compare the transfer accuracy of four different lingual retainer (LR) transfer methods using three-dimensional digital models. Materials and Methods Four groups of 17 patients each were created: finger transfer (FT), silicone key transfer (SKT), acrylic resin transfer (ART), and indirect bonding (IDB). At the end of orthodontic treatment, the mandibular dental casts of patients were scanned with the LR wire. Then, intraoral scanning of the mandibular arches was performed after bonding the retainer wires. Linear and angular measurements were made using software on superimposed digital models. Results Horizontal and vertical errors among the teeth were not significantly different among the FT, SKT, and ART groups. However, in the IDB group, linear transfer errors showed significant differences among the different teeth. The tip and rotation errors in the FT group were not significantly different among the teeth. The angular errors were lower in canines than in the incisors. In all measured parameters, the SKT group showed the lowest errors, whereas the FT group had the highest transfer errors in all parameters except vertical. Conclusions Among the transfer methods tested, SKT was determined to have the highest clinical accuracy.

scholarly journals Bracket transfer accuracy with two different three-dimensional printed transfer trays vs silicone transfer trays

2022 ◽  
Author(s):  
Lea Hoffmann ◽  
Hisham Sabbagh ◽  
Andera Wichelhaus ◽  
Andreas Kessler
Keyword(s):  
Three Dimensional ◽  
Processing System ◽  
Similar Distribution ◽  
Digital Light Processing ◽  
Directional Bias ◽  
Indirect Bonding ◽  
Significant Difference ◽  
Transfer Tray ◽  
Transfer Accuracy ◽  
Bracket Positioning

ABSTRACT Objectives To compare the transfer accuracy of two different three-dimensional printed trays (Dreve FotoDent ITB [Dreve Dentamid, Unna, Germany] and NextDent Ortho ITB [NextDent, Soesterberg, the Netherlands]) to polyvinyl siloxane (PVS) trays for indirect bonding. Materials and Methods A total of 10 dental models were constructed for each investigated material. Virtual bracket placement was performed on a scanned dental model using OnyxCeph (OnyxCeph 3D Lab, Chemnitz, Germany). Three-dimensional printed transfer trays using a digital light processing system three-dimensional printer and silicone transfer trays were produced. Bracket positions were scanned after the indirect bonding procedure. Linear and angular transfer errors were measured. Significant differences between mean transfer errors and frequency of clinically acceptable errors (<0.25 mm/1°) were analyzed using the Kruskal–Wallis and χ2 tests, respectively. Results All trays showed comparable accuracy of bracket placement. NextDent exhibited a significantly higher frequency of rotational error within the limit of 1° (P = .01) compared with the PVS tray. Although PVS showed significant differences between the tooth groups in all linear dimensions, Dreve exhibited a significant difference in the buccolingual direction only. All groups showed a similar distribution of directional bias. Conclusions Three-dimensional printed trays achieved comparable results with the PVS trays in terms of bracket positioning accuracy. NextDent appears to be inferior compared with PVS regarding the frequency of clinically acceptable errors, whereas Dreve was found to be equal. The influence of tooth groups on the accuracy of bracket positioning may be reduced by using an appropriate three-dimensional printed transfer tray (Dreve).

scholarly journals Computed tomography evaluation of palatal form in the transversal and sagittal fabrication process and the effect of first molar and canine crown angulations

2019 ◽  
Vol 28 ◽  
pp. 2633366X1989680
Author(s):  
Taljabini Yamen ◽  
Oz Ulas
Keyword(s):  
Orthodontic Treatment ◽  
Three Dimensional ◽  
Cone Beam ◽  
P Value ◽  
Dimensional Model ◽  
Three Dimensional Model ◽  
Angular Measurements ◽  
Left And Right ◽  
Dependent Samples ◽  
Cone Beam Tomography

The purpose of this study was to investigate changes in the palatal form in patients treated with and without premolar extractions. A total of 40 patients who had undergone orthodontic treatment (extraction and non-extraction) were divided into two groups coequally. Retrospective records were collected at pretreatment and at bracket removal. Stone casts were scanned by cone-beam tomography; linear and angular measurements on the three-dimensional model were then performed for both the sagittal direction and the transverse direction. Paired t-tests for dependent samples were used to compare results within the same group, and t-tests for independent samples were used to compare results between groups. A p value less than 0.05 was considered statistically significant. The sagittal palatal form increased in the non-extraction group, whereas it decreased in the extraction group. There was a decrement in the transversal palatal form in both groups. There were no differences or changes in molar or canine crown angulation in the non-extraction group. Conversely, distal tipping of the upper right first molar and distal tipping and lingual movement of both left and right upper canines were observed in the extraction group.

scholarly journals Apical root resorption due to orthodontic treatment detected by cone beam computed tomography

2012 ◽  
Vol 83 (2) ◽  
pp. 196-203 ◽  
Author(s):  
Iury O. Castro ◽  
Ana H. G. Alencar ◽  
José Valladares-Neto ◽  
Carlos Estrela
Keyword(s):  
Computed Tomography ◽  
Cone Beam Computed Tomography ◽  
Orthodontic Treatment ◽  
Root Resorption ◽  
Three Dimensional ◽  
Cone Beam ◽  
Apical Root Resorption ◽  
Gender And Age ◽  
Before And After

ABSTRACT Objective: To determine the frequency of apical root resorption (ARR) due to orthodontic treatment using cone beam computed tomography (CBCT) in a sample of 1256 roots from 30 patients. Materials and Methods: All patients had Class I malocclusion with crowding. Of the 30 patients evaluated, 11 were boys and 19 were girls; their mean age was 13 years (11 to 16 years). Orthodontic treatment followed the nonextraction treatment. CBCT images were obtained before and after orthodontic treatment, and ARR was determined using Axial Guided Navigation of CBCT images. Results: All patients had ARR. No statistically significant association was found between resorption frequency, gender, and age. ARR was detected using CBCT in 46% of all roots that underwent orthodontic treatment. Conclusions: CBCT was effective for detecting in vivo even minimal degrees of ARR due to orthodontic treatment and allowed three-dimensional evaluation of dental roots and visualization of palatine roots of maxillary molars. The highest frequencies and the most significant ARR occurred in incisors and distal roots of first maxillary and mandibular molars.

scholarly journals MODERN METHODS OF DIAGNOSIS IN ORTHODONTICS

2016 ◽  
Vol 1 (2) ◽  
pp. 10-13
Author(s):  
AV V Arkhipov ◽  
EA A Loginova ◽  
VD D Arkhipov
Keyword(s):  
Computed Tomography ◽  
Temporomandibular Joint ◽  
Cone Beam Computed Tomography ◽  
Orthodontic Treatment ◽  
Three Dimensional ◽  
Cone Beam ◽  
Cephalometric Analysis ◽  
Facial Region ◽  
Facial Skull

The paper presents the possibilities of the virtual planning of orthodontic treatment with programs In Vivo Anatomage and 3Shape Ortho Analyzer, which allows you to create an individual plan of orthodontic treatment. Using three-dimensional cephalometric analysis and cone-beam computed tomography eliminates the risk of complications during orthodontic tooth moving. Aim - to determine the main directions of application of three-dimensional cephalometric analysis in orthodontist’s practice Materials and methods. The study involved 20 patients aged between 18 and 35 years (women 85%, men 15%). All patients underwent cone-beam computed tomography of the facial region of the skull conducted on a tomograph with a matrix 16h10. To obtain the most objective data, a wide range of clinical and other diagnostic methods was used in the study: clinical (survey, visual examination of face and oral cavity, clinical functional tests), anthropometric (measurement of jaw models in the program 3Shape Ortho Analyzer), CBCT of the facial region of the skull and cervical part of the spine. The survey was conducted on every patient according to the developed protocol. 1. Assessment of the dental hard tissues (diagnosis of caries, pulpitis and periodontitis), periapical periodontal tissues, and the state of the cortical bone; construction of three-dimensional panoramic reconstruction to determine the parallelism of the roots and their position in the bone of the alveolar processes on the vestibular and lingual surfaces. 2. Assessment of the patency of airways. 3. Evaluation of the bone elements of the temporomandibular joint on both sides, determining the position of articular head in the glenoid fossa. 4. Three-dimensional cephalometric analysis. 5. Superimposition of the data of the facial skull computed tomography; analysis of the changes in the course of dental treatment. The results of research. The obtained CBCT of the facial skull, processed in the program In Vivo Anatomage version 5.2, allows specifying the status and location of the bony structures of the temporomandibular joint, sinuses, individual structural features of the upper and lower jaws, dental roots deep in the alveolar processes and their correlation to the cortical plate. Additional features of the program are the opportunity to study the airways, combination of the scanned plaster models in .Stl format and superimposition of one CT scan to the other to produce a report on the changes that occurred. Discussion. The computer program allows correction of congenital abnormalities of dentition, reducing the risk of complications to a minimum. Moreover, the expected result can be predicted at the initial stage of treatment. The main advantage of CBCT is the possibility to determine the exact anatomical parameters of a patient without overlapping of adjacent structures and projection distortion of the sizes of anatomical structures.

scholarly journals Comparison of the transfer accuracy of two digital indirect bonding trays for labial bracket bonding

2020 ◽  
Vol 91 (1) ◽  
pp. 67-73
Author(s):  
Ye Niu ◽  
Yunting Zeng ◽  
Zeyu Zhang ◽  
Wanghan Xu ◽  
Liwei Xiao
Keyword(s):  
Three Dimensional ◽  
Scanning System ◽  
Chi Square ◽  
Directional Bias ◽  
Bonding System ◽  
Indirect Bonding ◽  
Transfer Error ◽  
Chi Square Test ◽  
3D Printed ◽  
Transfer Accuracy

ABSTRACT Objectives To compare the transfer accuracy of two digital transfer trays, the three-dimensional printed (3D printed) tray and the vacuum-formed tray, in the indirect bonding of labial brackets. Materials and Methods Ten digital dental models were constructed by oral scans using an optical scanning system. 3D printed trays and vacuum-formed trays were obtained through the 3Shape indirect bonding system and rapid prototyping technology (10 in each group). Then labial brackets were transferred to 3D printed models, and the models with final bracket positioning were scanned. Linear (mesiodistal, vertical, buccolingual) and angular (angulation, torque, rotation) transfer errors were measured using GOM Inspect software. The mean transfer errors and prevalence of clinically acceptable errors (linear errors of ≤0.5 mm and angular errors of ≤2°) of two digital trays were compared using the Mann-Whitney U-test and the Chi-square test, respectively. Results The 3D printed tray had a lower mean mesiodistal transfer error (P < .01) and a higher prevalence of rotation error within the limit of 2° (P = .03) than did the vacuum-formed tray. Linear errors within 0.5 mm were higher than 90% for both groups, while torque errors within 2° were lowest at 50.9% and 52.9% for the 3D printed tray and vacuum-formed tray, respectively. Both groups had a directional bias toward the occlusal, mesial, and buccal. Conclusions The 3D printed tray generally scored better in terms of transfer accuracy than did the vacuum-formed tray. Both types of trays had better linear control than angular control of brackets.

scholarly journals Reproducibility of Digital Indirect Bonding Technique Using Three-dimensional (3d) Models and 3d-printed Transfer Trays

2019 ◽  
Vol 90 (1) ◽  
pp. 92-99 ◽  
Author(s):  
Maria Eduarda Assad Duarte ◽  
Bruno Frazão Gribel ◽  
Alice Spitz ◽  
Flavia Artese ◽  
José Augusto Mendes Miguel
Keyword(s):  
Repeated Measures ◽  
Intraclass Correlation ◽  
Three Dimensional ◽  
Correlation Coefficients ◽  
3D Models ◽  
Digital Models ◽  
Intraclass Correlation Coefficients ◽  
Indirect Bonding ◽  
3D Printed ◽  
Clinically Significant

ABSTRACT Objective To evaluate the reproducibility of digital tray transfer fit on digital indirect bonding by analyzing the differences in bracket positions. Materials and Methods Digital indirect bonding was performed by positioning brackets on digital models superimposed by tomography using Ortho Analyzer (3Shape) software. Thirty-three orthodontists performed indirect bonding on prototyped models of the same malocclusion using prototyped transfer trays for two types of brackets (MiniSprint Roth and BioQuick self-ligating). The models with brackets were scanned using an intraoral scanner (Trios, 3Shape). Superimpositions were made between the digital models obtained after indirect bonding and those from the original virtual setup. To analyze the differences in bracket positions, three planes were examined for each bracket: vertical, horizontal, and angulation. Three orthodontists repeated indirect bonding after 15 days, and Bland-Altman plots and intraclass correlation coefficients were used to evaluate inter- and intraevaluator reproducibility and reliability, respectively. Repeated-measures analysis of variance (ANOVA) was used to analyze the differences between bracket positions, and multivariate ANOVA was used to evaluate the influence of orthodontists' experience on the results. Results Differences between bracket positions were not statistically significant, except mesial-distal discrepancies in the BioQuick group (P = .016). However, differences were not clinically significant (horizontal varied from 0.04 to 0.13 mm; angulation, 0.45° to 2.03°). There was no significant influence of orthodontist experience and years of clinical practice on bracket positions (P = .314 and P = .158). The reproducibility among orthodontists was confirmed. Conclusions The reproducibility of digital indirect bonding was confirmed in terms of bracket positions using three-dimensional printed transfer trays.

A comparative assessment of transfer accuracy of two indirect bonding techniques in patients undergoing fixed mechanotherapy: A randomised clinical trial

2020 ◽  
pp. 146531252096857
Author(s):  
Vivek Chaudhary ◽  
Puneet Batra ◽  
Karan Sharma ◽  
Sreevatsan Raghavan ◽  
Vikram Gandhi ◽  
...  
Keyword(s):  
Controlled Trial ◽  
Previous History ◽  
Three Dimensional ◽  
Randomised Clinical Trial ◽  
Vertical Dimension ◽  
Indirect Bonding ◽  
Transfer Error ◽  
3D Printed ◽  
Randomised Controlled ◽  
Transfer Accuracy

Objectives To assess the transfer accuracy of three-dimensional (3D) printed transfer trays and compare them with transfer trays made up of polyvinyl siloxane (PVS) for use in indirect bonding. Design: This was a two-arm parallel prospective randomised controlled trial. Setting: The trial was undertaken at the outpatient department of a dental college. Participants: A total of 30 patients (18 men, 12 women) were randomly allocated to two groups. Methods: The inclusion criteria included patients with permanent and fully erupted dentition (age range = 17–24 years), Angles class I malocclusion with crowding <3 mm requiring non-extraction treatment, good oral hygiene and no previous history of orthodontic treatment. Blinding was applicable only for outcome assessment. Indirect bonding was performed by the primary investigator for both the groups. Digital images of the pre-transfer and post-transfer brackets were obtained by means of an intra-oral scanner and compared using software. Superimpositions of pre- and post-transfer images were done to determine the transfer error for linear and angular variables for all tooth types. Results: A total of 600 teeth were bonded, 300 each for both groups. Statistically significant differences were observed in all dimension between the two groups, with 3D-printed trays being more accurate than PVS trays except in the vertical dimension ( P < 0.05). The prevalence of clinically unacceptable transfer errors revealed that most of the transfer errors were in the vertical dimensions for 3D-printed trays. Conclusion: 3D-printed trays are more accurate than PVS trays except for transfers in vertical dimension.

scholarly journals In Vivo Comparison of Conventional and Cone Beam CT Synthesized Cephalograms

2008 ◽  
Vol 78 (5) ◽  
pp. 873-879 ◽  
Author(s):  
Vandana Kumar ◽  
John Ludlow ◽  
Lucia Helena Soares Cevidanes ◽  
André Mol
Keyword(s):  
Repeated Measures ◽  
Cone Beam Ct ◽  
Statistical Significance ◽  
Three Dimensional ◽  
Cone Beam ◽  
Volume Data ◽  
Linear Measurements ◽  
Lateral Cephalograms ◽  
Angular Measurements

Abstract Objective: To compare measurements from synthesized cone-beam computed tomography (CBCT) lateral cephalograms using orthogonal and perspective projections with those from conventional cephalometric radiographs. Materials and Methods: Thirty-one patients were imaged using CBCT and conventional cephalometry. CBCT volume data were imported in Dolphin 3D. Orthogonal and perspective lateral cephalometric radiographs were created from three-dimensional (3D) virtual models. Twelve linear and five angular measurements were made on synthesized and conventional cephalograms in a randomized fashion. Conventional image measurements were corrected for known magnification. Linear and angular measurements were compared between image modalities using repeated measures analysis of variance. Statistical significance was defined as an α level of .01. Results: With the exception of the Frankfort-mandibular plane angle (P &lt; .0001), angular measurements were not statistically different for any modality (P &gt; .01). Linear measurements, whether based on soft or hard tissue landmarks, were not statistically different (P &gt; .01). Conclusions: Measurements from in vivo CBCT synthesized cephalograms are similar to those based on conventional radiographic images. Thus, additional conventional imaging may generally be avoided when CBCT scans are acquired for orthodontic diagnosis.

scholarly journals Transfer accuracy of 3D-printed trays for indirect bonding of orthodontic brackets:

2022 ◽  
Author(s):  
Petra C. Bachour ◽  
Robert Klabunde ◽  
Thorsten Grünheid
Keyword(s):  
Positional Accuracy ◽  
Acceptable Limit ◽  
Indirect Bonding ◽  
3D Printed ◽  
Scan Data ◽  
Mean Differences ◽  
Bracket Position ◽  
Transfer Accuracy ◽  
Bracket Positioning

ABSTRACT Objectives To evaluate the transfer accuracy of 3D-printed indirect bonding trays constructed using a fully digital workflow in vivo. Materials and Methods Twenty-three consecutive patients had their incisors, canines, and premolars bonded using fully digitally designed and 3D-printed transfer trays. Intraoral scans were taken to capture final bracket positioning on teeth after bonding. Digital models of postbonding scans were superimposed on those of corresponding virtual bracket setups, and bracket positioning differences were quantified. A total of 363 brackets were evaluated. One-tailed t-tests were used to determine whether bracket positioning differences were within the limit of 0.5 mm in mesiodistal, buccolingual, and occlusogingival dimensions, and within 2° for torque, tip, and rotation. Results Mean bracket positioning differences were 0.10 mm, 0.10 mm, and 0.18 mm for mesiodistal, buccolingual, and occlusogingival measurements, respectively, with frequencies of bracket positioning within the 0.5-mm limit ranging from 96.4% to 100%. Mean differences were significantly within the acceptable limit for all linear dimensions. Mean differences were 2.55°, 2.01°, and 2.47° for torque, tip, and rotation, respectively, with frequencies within the 2°-limit ranging from 46.0% to 57.0%. Mean differences for all angular dimensions were outside the acceptable limit; however, this may have been due to limitations of scan data. Conclusions Indirect bonding using 3D-printed trays transfers planned bracket position from the digital setup to the patient's dentition with a high positional accuracy in mesiodistal, buccolingual, and occlusogingival dimensions. Questions remain regarding the transfer accuracy for torque, tip, and rotation.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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