Treatment of Moderately Crowded Teeth Using Lingual Fixed Appliance Prepared by a Modified HIRO® Technique: A Case Report and Method Description

There are various manual laboratory methods available for indirect positioning and bonding of lingual brackets. The manual setup has limitations because of its complicated laboratory procedures and requires time and specialized laboratory equipment. In addition, the manual method is also prone to human errors. In this case report, a description of a new method of laboratory preparation for the indirect bonding of lingual brackets is given by merging recent advances in digital dentistry with some of the ordinary manual steps in this field. Therefore, the well-known HIRO® technique has been modified by using the three-dimensional (3D) virtual setup instead of the traditional manual setup. This method does not require the use of any specialized laboratory equipment, and it is also cost-effective for patients who cannot afford fully customized lingual appliances. In this modified technique, 3Shape Ortho Analyzer™ software (3Shape, Copenhagen, Denmark) and a 3D printer (Prusa® i3 mk3; Prusa Research, Prague, Czech Republic) were used to align the teeth three-dimensionally into their desired positions and to produce the final working printed model on which lingual brackets were placed, and transfer caps were fabricated for clinical use.