Research Article|Articles in Press

3D printed aligners: Material science, workflow and clinical applications

  • Nearchos Panayi
    Corresponding author.
    School of Dentistry, European University Cyprus, Nicosia, Cyprus

    Clinic of Orthodontics & Pediatric Dentistry, Center of Dental Medicine, University of Zurich, Zurich, Switzerland

    private office Limassol, Cyprus
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  • Jung-Yeol Cha
    Director for Planning & Management Dental Hospital, Department of Orthodontics, Dental College, Yonsei University, 50-1 Yonseiro, Seodaemun-gu, Seoul 120-752, Korea
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  • Ki Beom Kim
    Department of Orthodontics, Center for Advanced Dental Education, Saint Louis University, 3320 Rutger Street, Saint Louis, MO 63104, United States
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Published:January 11, 2023DOI:


      Clear aligner orthodontic treatment is not a new treatment modality. Treatment with the use of plastic invisible removable appliances counts more than 80 years when Kesling introduced the tooth positioner, Sheridan introduced the Essix aligner and Align technology its aligners. In-house designing and aligner fabrication has been around for more than 10 years. The last years a digital techonological and material advancement has changed the process of aligner manufacturing from the plastic foil thermoforming procedure to a direct aligner printing one. Direct aligner printing posses advantages and some disadvantages compared to the traditional thermoforming procedure. The aligner designing and printing workflow entails steps that are sensitive to errors that must be carefully analyzed and studied through scientific research. Due to the versatile printed aligner designing capabilities, aligners can be designed to fulfill specific clinical needs. A few evidence based scientific studies have been published which help to understand and optimize the final printed outcome. Despite that, more studies are needed in order to overcome difficulties and create an appliance that will meet the demands of a succesfull orthodontic treatment.
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