{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T09:09:53Z","timestamp":1788858593732,"version":"build-2803163510"},"reference-count":46,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T00:00:00Z","timestamp":1788825600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Dent. J.","Dentistry Journal"],"abstract":"<jats:p>Objectives: This systematic review aims to compare the forces and moments generated by thermoforming aligners and direct-printed aligners in guiding tooth movement in orthodontic patients, evaluating their impact on orthodontic outcomes. Methods: A systematic search was conducted in PubMed, Web of Science, and Scopus databases, covering studies on thermoforming and direct-printed aligners from inception to October 2024. Eligible studies included randomized controlled trials, quasi-experimental studies, and observational studies assessing forces and moments generated by these aligners on teeth. In vitro studies pertinent to the topic were also considered. Data extraction focused on study characteristics, aligner details, force and moment measurements, and clinical outcomes. Quality assessment utilized the ROBINS- I for Risk of Bias. The review has been registered on PROSPERO CRD42024620341. Results: A total of nine studies met the inclusion criteria. Findings indicate that thermoforming aligners, while effective in initial force application, exhibit significant force decay over time due to material stress relaxation. In contrast, direct-printed aligners maintain more consistent force levels, potentially resulting in more predictable and sustained tooth movement. Both aligner types vary in their ability to control force direction and magnitude, with direct-printed aligners showing advantages in customization and force retention. Conclusions: The biomechanical properties of thermoforming and direct-printed aligners offer distinct advantages and limitations. Direct-printed aligners may enhance clinical predictability and reduce treatment time through consistent force application, though further research is necessary to validate these benefits in clinical settings. This review underscores the importance of material selection and fabrication method in optimizing orthodontic outcomes.<\/jats:p>","DOI":"10.3390\/dj14090577","type":"journal-article","created":{"date-parts":[[2026,9,8]],"date-time":"2026-09-08T08:10:22Z","timestamp":1788855022000},"page":"577","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Forces and Moments Generated by Thermoforming Aligners and Direct-Printed Aligners: A Systematic Review"],"prefix":"10.3390","volume":"14","author":[{"given":"Pritam","family":"Mohanty","sequence":"first","affiliation":[{"name":"Department of Orthodontics and Dentofacial Orthopaedics, Institute of Dental Sciences, Siksha \u2018O\u2019 Anusandhan University, Bhubaneswar 751029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7519-1812","authenticated-orcid":false,"given":"Saundarya","family":"Priyadarshini","sequence":"additional","affiliation":[{"name":"Department of Paediatric Surgery, All India Institute of Medical Sciences, New Delhi 110029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-5438-543X","authenticated-orcid":false,"given":"Debapreeti","family":"Mohanty","sequence":"additional","affiliation":[{"name":"Department of Conservative Dentistry and Endodontics, Institute of Dental Sciences, Siksha \u2018O\u2019 Anusandhan University, Bhubaneswar 751029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8770-5297","authenticated-orcid":false,"given":"Margherita","family":"Tumedei","sequence":"additional","affiliation":[{"name":"Department of Biomedical, Surgical and Dental Sciences, Universit\u00e0degli Studi di Milano, 20122 Milan, Italy"},{"name":"Fondazione IRCCS Ca\u2019Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7144-0984","authenticated-orcid":false,"given":"Massimo","family":"Del Fabbro","sequence":"additional","affiliation":[{"name":"Department of Biomedical, Surgical and Dental Sciences, Universit\u00e0degli Studi di Milano, 20122 Milan, Italy"},{"name":"Fondazione IRCCS Ca\u2019Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Parameswaran","family":"Tirunelveli Mani","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, Tagore Dental College and Hospital, Rathinamangalam 600127, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Partha Pratim","family":"Chaudhary","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, R. Ahmed Dental College & Hospital, Kolkata 700014, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Balaji","family":"Krishnan","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, Tagore Dental College and Hospital, Rathinamangalam 600127, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Monalisa","family":"Das","sequence":"additional","affiliation":[{"name":"Department of Orthodontics and Dentofacial Orthopaedics, Institute of Dental Sciences, Siksha \u2018O\u2019 Anusandhan University, Bhubaneswar 751029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bhagabati Prasad","family":"Dash","sequence":"additional","affiliation":[{"name":"Department of Orthodontics and Dentofacial Orthopaedics, Kalinga Institute of Dental Sciences, Bhubaneswar 751024, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-6429-4425","authenticated-orcid":false,"given":"Bhabani Shankar","family":"Biswal","sequence":"additional","affiliation":[{"name":"Department of Orthodontics and Dentofacial Orthopaedics, Institute of Dental Sciences, Siksha \u2018O\u2019 Anusandhan University, Bhubaneswar 751029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2354-361X","authenticated-orcid":false,"given":"Funda","family":"Goker","sequence":"additional","affiliation":[{"name":"Department of Biomedical, Surgical and Dental Sciences, Universit\u00e0degli Studi di Milano, 20122 Milan, Italy"},{"name":"Fondazione IRCCS Ca\u2019Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy"},{"name":"Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Istanbul Ayd\u0131n University, 34000 Istanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Saurav","family":"Panda","sequence":"additional","affiliation":[{"name":"Department of Periodontics, Institute of Dental Sciences, Siksha \u2018O\u2019 Anusandhan University, Bhubaneswar 751029, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Tartaglia, G.M., Mapelli, A., Maspero, C., Santaniello, T., Serafin, M., Farronato, M., and Caprioglio, A. 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