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

Abstract

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.

Transfer Accuracy of Two 3D Printed Trays for Indirect Bracket Bonding—An In Vitro Pilot Study

“…In the literature, different procedures for digitizing study models, e.g., intraoral scanners, 3D-model scanners or cone beam computed tomography (CBCT), were described for assessing the accuracy of transfer trays in digital workflows [29][30][31][32]. Matching intraoral scans (IOS) with the virtually planned reference models seems to be used most frequently and has the advantage that this workflow can be easily applied to clinical as well as in vitro settings, whereas microcomputed tomography (micro-CT) is limited to in vitro studies only.…”

“…Regarding the amount of deviations, linear discrepancies ≤ 0.5 mm and angular deviations of ≤2 • were considered to be acceptable as suggested by The American Board of Orthodontists (ABO) [37] and further studies [21,32], despite some authors recommending more strict ranges [30,38].…”

A Novel Digital Technique for Measuring the Accuracy of an Indirect Bonding Technique Using Fixed Buccal Multibracket Appliances

“…Grünheid et al reported that the anterior teeth (−0.012 ± 0.009 mm in mesio-distal measures, 0.026 ± 0.013 mm in vertical measures, and 0.0103° ± 0.085, 0.061° ± 0.005, and 0.235° ± 0.010 for the torque, tip, and rotation, respectively) showed more accurate indirect bonding positions of the fixed multibracket appliances than the posterior teeth did (−0.063 ± 0.033 mm in mesio-distal measures, 0.035 ± 0.017 mm in vertical measures, and −0.268° ± 0.520, −0.213° ± 0.445, and 0.405° ± 0.335 for the torque, tip, and rotation, respectively) [ 19 ]. Süpple et al found more displacement in the molar teeth 21, and Kim et al reported this discrepancy in the posterior teeth in the height of the cusps [ 20 ]. However, in the present study, this result was found just in the mesio-distal measurement.…”

Smart 3D Printed Hydrogel Skin Wound Bandages: A Review

“…Incorporating gluconic acid with hydrogel wound dressings stabilizes the pH ranges that are significant for bacterial protection. For instance, maintaining wound pH in the range of 3.2–4.5 by use of gluconic acid, creates an environment that prevents pathogen growth [ 225 ]. In addition, gluconic acid may enhance environmental moisture, and reduce inflammation and infection [ 225 ].…”

“…For instance, maintaining wound pH in the range of 3.2–4.5 by use of gluconic acid, creates an environment that prevents pathogen growth [ 225 ]. In addition, gluconic acid may enhance environmental moisture, and reduce inflammation and infection [ 225 ]. Adding nanofiller to the hydrogel makes transporting active agents, such as drugs, feasible by moving in and out of skin via diffusion and active transport.…”