Transfer accuracy of vinyl polysiloxane trays for indirect bonding

ABSTRACT Objective: To elicit the magnitude, directional bias, and frequency of bracket positioning errors caused by the transfer of brackets from a dental cast to the patient’s dentition in a clinical setting. Materials and Methods: A total of 136 brackets were evaluated. The brackets were placed on dental casts and scanned using cone beam computed tomography (CBCT) to capture 3-D positioning data. The brackets were then transferred to the patient’s dentition with an indirect bonding method using vinyl polysiloxane (VPS) trays and later scanned using CBCT to capture the final bracket positioning on the teeth. Virtual models were constructed from the two sets of scan data and digitally superimposed utilizing best-fit, surface-based registration. Individual bracket positioning differences were quantified using customized software. One-tailed t tests were used to determine whether bracket positioning was within limits of 0.5 mm in the mesiodistal, buccolingual, and vertical dimensions, and 2° for torque, tip, and rotation. Results: Individual bracket positioning differences were not statistically significant, indicating, in general, final bracket positions within the selected limits. Transfer accuracy was lowest for torque (80.15%) and highest for mesiodistal and buccolingual bracket placement (both 98.53%). There was a modest directional bias toward the buccal and gingival. Conclusion: Indirect bonding using VPS trays transfers the planned bracket position from the dental cast to the patient’s dentition with generally high positional accuracy.

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

The Angle Orthodontist ◽

10.2319/073021-596.1 ◽

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.

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

The Angle Orthodontist ◽

10.2319/040821-283.1 ◽

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).

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Accurate Bracket Placement with an Indirect Bonding Method Using Digitally Designed Transfer Models Printed in Different Orientations—An In Vitro Study

Journal of Clinical Medicine ◽

10.3390/jcm10092002 ◽

2021 ◽

Vol 10 (9) ◽

pp. 2002

Author(s):

Julia Süpple ◽

Julius von Glasenapp ◽

Eva Hofmann ◽

Paul-Georg Jost-Brinkmann ◽

Petra Julia Koch

Keyword(s):

In Vitro Study ◽

Angular Dimension ◽

3D Printer ◽

Digital Light Processing ◽

Indirect Bonding ◽

Bonding Method ◽

Plaster Models ◽

Transfer Accuracy ◽

Transfer Models

Objective: A digital workflow opens up new possibilities for the indirect bonding (IDB) of brackets. We tested if the printing orientation for bracket transfer models on the build platform of a 3D printer influences the accuracy of the following IDB method. We also evaluated the clinical acceptability of the IDB method combining digitally planned and printed transfer models with the conventional fabrication of pressure-molded transfer trays. Materials and Methods: In total, 27 digitally planned bracket transfer models were printed with both 15° and 75° angulation from horizontal plane on the build platform of a digital light processing (DLP) printer. Brackets were temporarily bonded to the transfer models and pressure-molded trays were produced on them. IDB was then performed using the trays on the respective plaster models. The plaster models were scanned with an optical scanner. Digitally planned pre-bonding and scanned post-bonding bracket positions were superimposed with a software and resulted in three linear and three angular deviations per bracket. Results: No statistically significant differences of the transfer accuracy of printed transfer models angulated 15° or 75° on the 3D printer build platform were found. About 97% of the linear and 82% of the angular deviations were within the clinically acceptable range of ±0.2 mm and ±1°, respectively. The highest inaccuracies in the linear dimension occurred in the vertical towards the gingival direction and in the angular dimension in palatal crown torque. Conclusion: For the IDB method used, the printing orientation on the build platform did not have a significant impact on the transfer accuracy.

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

The Angle Orthodontist ◽

10.2319/013120-70.1 ◽

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.

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Transfer accuracy of two indirect bonding techniques—an in vitro study with 3D scanned models

European Journal of Orthodontics ◽

10.1093/ejo/cjy006 ◽

2018 ◽

Vol 40 (5) ◽

pp. 549-555 ◽

Cited By ~ 9

Author(s):

Johanna Schmid ◽

Daniel Brenner ◽

Wolfgang Recheis ◽

Philipp Hofer-Picout ◽

Martin Brenner ◽

...

Keyword(s):

In Vitro Study ◽

Vitro Study ◽

Indirect Bonding ◽

Transfer Accuracy

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Three-Dimensional Digital Superimposition of Orthodontic Bracket Position by Using a Computer-Aided Transfer Jig System: An Accuracy Analysis

Sensors ◽

10.3390/s21175911 ◽

2021 ◽

Vol 21 (17) ◽

pp. 5911

Author(s):

Jae-Hyun Park ◽

Jin-Young Choi ◽

Song Hee Oh ◽

Seong-Hun Kim

Keyword(s):

Three Dimensional ◽

Orthodontic Bracket ◽

Bonding System ◽

Anterior Teeth ◽

Computer Aided ◽

Orthodontic Patients ◽

Dental Models ◽

Bracket Position ◽

3D Software ◽

Bracket Positioning

Accurate bracket placement is essential for successful orthodontic treatment. An indirect bracket bonding system (IDBS) has been developed to ensure proper bracket positioning with three-dimensional computer-aided transfer jigs. The purpose of this study was to investigate the accuracy of bracket positioning by a one-body transfer jig according to the tooth type and presence/absence of a resin base. In total, 506 teeth from 20 orthodontic patients were included in this study. After initial dental models were scanned, virtual setup and bracket positioning procedures were performed with 3D software. Transfer jigs and RP models were fabricated with a 3D printer, and brackets were bonded to the RP model with or without resin base fabrication. The best-fit method of 3D digital superimposition was used to evaluate the lineal and angular accuracy of the actual bracket position compared to a virtual bracket position. Although all the measurements showed significant differences in position, they were clinically acceptable. Regarding the tooth types, premolars and molars showed higher accuracy than anterior teeth. The presence or absence of a resin base did not consistently affect the accuracy. In conclusion, the proper application of IDBS should be performed considering the errors, and resin base fabrication might not be essential in ensuring high-accuracy IDBS.

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The Reliability of Positioning Pre-adjusted Brackets: An In Vitro Study

British Journal of Orthodontics ◽

10.1179/bjo.19.1.25 ◽

1992 ◽

Vol 19 (1) ◽

pp. 25-34 ◽

Cited By ~ 15

Author(s):

Nigel Geoffrey Taylor ◽

Paul Andrew Cook

Keyword(s):

In Vitro Study ◽

Vitro Study ◽

Clinical Implications ◽

Straight Wire ◽

Anterior Teeth ◽

Image Analyser ◽

Bracket Position ◽

Bracket Positioning

To investigate the reliability of bracket positioning, twelve operators, familiar with the straight-wire appliance, placed 0.022” straight-wire brackets on the anterior teeth of a typodont study model, on three different occasions. Bracket position was assessed using a Magiscan image analyser. Angular judgements by the operators were found to be less consistently identified than linear assessments. Slot angulation showed the largest variability and vertical bracket placement the least. The clinical implications of bracket misplacement are discussed.

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

The Angle Orthodontist ◽

10.2319/020921-118.1 ◽

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.

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