{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,29]],"date-time":"2026-09-29T18:21:34Z","timestamp":1790706094787,"version":"4.1.0"},"reference-count":47,"publisher":"Oxford University Press (OUP)","issue":"3","license":[{"start":{"date-parts":[[2026,5,26]],"date-time":"2026-05-26T00:00:00Z","timestamp":1779753600000},"content-version":"vor","delay-in-days":53,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Seed Fund for Collaborative Research of the University of Hong Kong","award":["2307102537"],"award-info":[{"award-number":["2307102537"]}]},{"name":"International Orthodontics Foundation Young Research"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,4,3]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objectives<\/jats:title>\n                    <jats:p>This systematic review aims to evaluate the clinical applicability of automated 3D facial asymmetry assessment methods based on 3D facial scans.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Search Methods<\/jats:title>\n                    <jats:p>A comprehensive search of electronic databases (PubMed, Web of Science, EMBASE, Medline, and Scopus) and manual literature searches were conducted in April 2025.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Selection Criteria<\/jats:title>\n                    <jats:p>Studies that were published in English and evaluated the validity or reliability of automated asymmetry assessment methods in 3D facial scans for medical or biological settings were included.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Data Collection and Analysis<\/jats:title>\n                    <jats:p>Two reviewers independently screened the articles for eligibility. Risk of bias was assessed using QUADAS-2, and the certainty of evidence was graded using the Grading of Recommendations Assessment, Development, and Evaluation framework.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Fourteen studies met the inclusion criteria and were analyzed for methodology, validity, and reliability. Methodologies for assessing facial asymmetry were categorized into four approaches: landmark-based, depth-stratified, original-mirror alignment, and template-based approaches. While landmark and depth-stratified methods rely on sparse data, original-mirror and template-based methods enable comprehensive surface analysis. Six studies evaluating validity against alternative methods, synthetic ground truth, or human ratings consistently demonstrated moderate-to-strong correlation coefficients and classification accuracy. Reliability was examined across nine studies using repeated measurements and multi-observer designs, generally showing minimal measurement variation. Notably, methodological analysis revealed that original-mirror alignment, typically implemented using unconstrained iterative closest point (ICP)-based best-fit registration, is susceptible to registration errors (the \u201cPinocchio effect\u201d) in cases of severe asymmetry, whereas template-based methods mitigate this through correspondence transfer and weighted registration strategies that stabilize anatomical alignment.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Limitations<\/jats:title>\n                    <jats:p>The review is limited by a high risk of bias in primary studies and significant methodological heterogeneity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Despite \u201cvery low\u201d certainty evidence, template-based approaches that transfer anatomical correspondence and apply weighted registration appear preferable due to their robustness against localized deformities. Conversely, original-mirror alignment, typically implemented via unconstrained ICP, remains a practical alternative for mild asymmetry. Future research should prioritize end-to-end deep learning automation, dynamic analysis, and the development of accessible, open-source tools to bridge the gap between technical innovation and routine clinical practice.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Registration<\/jats:title>\n                    <jats:p>PROSPERO (CRD420251025105).<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1093\/ejo\/cjag012","type":"journal-article","created":{"date-parts":[[2026,2,3]],"date-time":"2026-02-03T12:39:27Z","timestamp":1770122367000},"source":"Crossref","is-referenced-by-count":1,"title":["Automated assessment of 3D facial asymmetry: a systematic review"],"prefix":"10.1093","volume":"48","author":[{"given":"Jiale","family":"Peng","sequence":"first","affiliation":[{"name":"Division of Paediatric Dentistry and Orthodontics, Faculty of Dentistry, The University of Hong Kong , Hong Kong SAR 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