Journal of Aligner Orthodontics, 03/2022

Artificial intelligence is now involved in many aspects of our everyday life. In digital orthodontic practice in particular, practitioners are constantly and mostly unknowingly confronted with different levels of implementations of artificial intelligence. The present article, the third in a three-part series, will seek to shed light on some of these algorithms using common examples from a standard orthodontic digital workflow. Keywords: aligner orthodontics, artificial intelligence, digital orthodontics, machine learning

The present article describes the material properties of CA Pro (Scheu Dental, Iserlohn, Germany), a novel aligner foil, and demonstrates its performance in the orthodontic treatment of two cases with different characteristics. Keywords: aligner, aligner material, biomaterials, digital orthodontics, materials

Objective: To illustrate the production and clinical application of a positioner made entirely from thermoplastic polyurethane using CAD/CAM technology and fused filament fabrication 3D printing for finishing after multibracket treatment. Materials and methods: Directly after removal of the multibracket appliance, both arches were scanned (T0), including a construction bite to record the desired relationship. After mesh repair, optimisation and segmentation, a visual treatment objective was generated for finishing (maximum range of movement 0.25 to 0.40 mm) using OnyxCeph³ 3D Lab (Image Instruments, Chemnitz, Germany) (T1). Virtual aligners with a thickness of 2.0 mm were constructed over the visual treatment objective, followed by edge smoothing and structural control. Support construction and slicing were done using Simplify3D (Simplify3D, Cincinnati, OH, USA). The positioner was made from medical thermoplastic polyurethane (layer height 0.2 mm) through fused filament fabrication 3D printing and was inserted 1 day after debonding. The patient was instructed to wear the appliance for 24 hours a day except when eating and exercising. A second scan was taken after 14 days (T2). The tooth movements were measured, visualised and compared with the visual treatment objective by superimposing the scans. Results: Tooth movements in the maxilla ranged between 0.10 and 0.26 mm in translation and 0.1 to 1.2 degrees in rotation; the respective values for the mandible were 0.10 to 0.34 mm and 0.9 degrees. The extent of the tooth movement differed depending on the type of tooth and the direction of movement. Conclusion: For the first time, a custom-made, clinically applicable CAD/CAM generated positioner made from thermoplastic polyurethane was produced through fused filament fabrication 3D printing. Keywords: 3D printing, CAD/CAM, fused filament fabrication, positioner

This case report demonstrates the hybrid treatment of anterior open bite in the early mixed dentition using a hyrax expansion appliance and the Invisalign First system (Align Technology, San Jose, CA, USA). A bonded hyrax expander (Dentaurum, Ispringen, Germany) was used to expand the maxilla and Invisalign First was employed to correct the open bite. Both of these problems were addressed successfully using this hybrid approach. It is crucial to consider the limitations and strengths of clear aligners when creating the treatment plan to achieve predictable outcomes. Closure of anterior open bite with Invisalign First was predictable and successful in the present patient. Keywords: aesthetics, ClinCheck software, evidence-based practice, growing patient, interceptive treatment, Invisalign, mixed dentition, open bite