Indirect orthodontic bonding with drop-shaped hot glue tray: a simple and cost-effective technique

Despite being associated with more accuracy, the indirect bonding procedure is not yet the gold standard, probably because of sensitivity of the numerous variables that must be controlled. The aim of this article was to present a modified, standardized, and low-cost indirect bonding technique that allows this procedure to be performed successfully. The technique covers an initial clinical stage, to obtain the models; a laboratory stage, which involves placement of brackets on the models following the facial axis of the clinical crown and the labial projection of the marginal ridges of the posterior teeth and construction of transfer tray using hot glue; and a second clinical stage, to properly transfer the brackets to patient’s teeth. Hot glue used to build the tray molds the teeth and perfectly adapts to the teeth, having enough stiffness to maintain their anatomy and the position of the brackets, but also presenting adequate flexibility to allow removal of the tray avoiding excessive stress over the brackets. In conclusion, the new simplified indirect bonding technique presented here provides a precise placement of brackets on the models, a cheaper way to transfer them to patient, and an easy removal of transfer tray, being a very simple and cost-effective method.

>35% 5-junction space solar cells based on the direct bonding technique

Multijunction solar cells are the highest efficiency photovoltaic devices yet demonstrated for both space and terrestrial applications. In recent years five-junction cells based on the direct semiconductor bonding technique (SBT), demonstrates space efficiencies >35% and presents application potentials. In this paper, the major challenges for fabricating SBT 5J cells and their appropriate strategies involving structure tunning, band engineering and material tailoring are stated, and 4-cm 2 35.4% (AM0, one sun) 5J SBT cells are presented. Further efforts on detailed optical managements are required to improve the current generating and matching in subcells, to achieve efficiencies 36%–37%, or above.

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

The aim of this study was to analyze the accuracy and predictability of the indirect bonding technique of fixed buccal multibracket appliances using a customized iterative closest point algorithm. Materials and Methods: A total of 340 fixed buccal multibracket appliances were virtually planned and bonded on 34 experimental anatomically based acrylic resin models by using orthodontic templates designed and manufactured to indirectly bond the fixed buccal multibracket appliances. Afterwards, the models were submitted to a three-dimensional impression technique by an intraoral scanner, and the standard tessellation language digital files from the virtual planning and the digital impression were aligned, segmented, and realigned using morphometric software. Linear positioning deviations (mm) of the fixed buccal multibracket appliances were quantified at mesio-distal, bucco-lingual/palatal, and gingival/occlusal (vertical) planes, and angular deviations (°) were also recorded by analyzing the torque, tip, and rotation using a customized iterative closest point algorithm, the script for which allowed for an accuracy measurement procedure by comparing the tessellation network positioning of both standard tessellation language digital files. Results: The mean mesio-distal deviation was −0.065 ± 0.081 mm, the mean bucco-lingual/palatal deviation was 0.129 ± 0.06 m, the mean vertical deviation was −0.094 ± 0.147 mm, the mean torque deviation was −0.826 ± 1.721°, the mean tip deviation was −0.271 ± 0.920°, and the mean rotation deviation was −0.707 ± 0.648°. Conclusion: The indirect bonding technique provides accurate and predictable positioning of fixed buccal multibracket appliances.