{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T07:25:45Z","timestamp":1791876345526,"version":"4.3.4"},"reference-count":48,"publisher":"Public Library of Science (PLoS)","issue":"11","license":[{"start":{"date-parts":[[2023,11,27]],"date-time":"2023-11-27T00:00:00Z","timestamp":1701043200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"FLAG-ERA grant","award":["JTC 2019 project MARGO"],"award-info":[{"award-number":["JTC 2019 project MARGO"]}]},{"DOI":"10.13039\/501100003448","name":"General Secretariat for Research and Technology","doi-asserted-by":"publisher","award":["T11ERA4-00017"],"award-info":[{"award-number":["T11ERA4-00017"]}],"id":[{"id":"10.13039\/501100003448","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:p>Symmetry is a fundamental biological concept in all living organisms. It is related to a variety of physical and social traits ranging from genetic background integrity and developmental stability to the perception of physical appearance. Within this context, the study of human facial asymmetry carries a unique significance. Here, we validated an efficient method to assess 3D facial surface symmetry by best-fit approximating the original surface to its mirrored one. Following this step, the midsagittal plane of the face was automatically defined at the midpoints of the contralateral corresponding vertices of the superimposed models and colour coded distance maps were constructed. The method was tested by two operators using facial models of different surface size. The results show that the midsagittal plane definition was highly reproducible (maximum error &lt; 0.1 mm or\u00b0) and remained robust for different extents of the facial surface model. The symmetry assessments were valid (differences between corresponding bilateral measurement areas &lt; 0.1 mm), highly reproducible (error &lt; 0.01 mm), and were modified by the extent of the initial surface model. The present landmark-free, automated method to assess facial asymmetry and define the midsagittal plane of the face is accurate, objective, easily applicable, comprehensible and cost effective.<\/jats:p>","DOI":"10.1371\/journal.pone.0294528","type":"journal-article","created":{"date-parts":[[2023,11,27]],"date-time":"2023-11-27T19:13:01Z","timestamp":1701112381000},"page":"e0294528","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":12,"title":["Facial asymmetry and midsagittal plane definition in 3D: A bias-free, automated method"],"prefix":"10.1371","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3180-6272","authenticated-orcid":true,"given":"Nikolaos","family":"Gkantidis","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jasmina","family":"Opacic","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georgios","family":"Kanavakis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christos","family":"Katsaros","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6501-8709","authenticated-orcid":true,"given":"Demetrios","family":"Halazonetis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2023,11,27]]},"reference":[{"key":"pone.0294528.ref001","doi-asserted-by":"crossref","first-page":"1727","DOI":"10.1111\/j.1420-9101.2006.01175.x","article-title":"Fluctuating asymmetry and developmental instability in evolutionary biology: past, present and future","volume":"19","author":"SV Dongen","year":"2006","journal-title":"J Evol Biol"},{"key":"pone.0294528.ref002","doi-asserted-by":"crossref","first-page":"1638","DOI":"10.1098\/rstb.2010.0404","article-title":"Facial attractiveness: evolutionary based research","volume":"366","author":"AC Little","year":"2011","journal-title":"Philos Trans R Soc Lond B Biol Sci"},{"issue":"Pt 4","key":"pone.0294528.ref003","doi-asserted-by":"crossref","first-page":"361","DOI":"10.1038\/hdy.1992.51","article-title":"Fluctuating asymmetry: a biological monitor of environmental and genomic stress","volume":"68","author":"PA Parsons","year":"1992","journal-title":"Heredity (Edinb)."},{"key":"pone.0294528.ref004","doi-asserted-by":"crossref","first-page":"1789","DOI":"10.3390\/sym12111789","article-title":"Breaking Symmetry: Fluctuating Asymmetry and Geometric Morphometrics as Tools for Evaluating Developmental Instability under Diverse Agroecosystems.","volume":"12","author":"HA Ben\u00edtez","year":"2020","journal-title":"Symmetry"},{"key":"pone.0294528.ref005","doi-asserted-by":"crossref","first-page":"843","DOI":"10.3390\/sym7020843","article-title":"Analyzing fluctuating asymmetry with geometric morphometrics: concepts, methods, and applications.","volume":"7","author":"C. 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