{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,6]],"date-time":"2026-07-06T14:02:27Z","timestamp":1783346547534,"version":"3.54.6"},"reference-count":37,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2021,12,8]],"date-time":"2021-12-08T00:00:00Z","timestamp":1638921600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The purpose of this study was to develop a technique to record the natural head position (NHP) of a subject using the scout images of cone beam computerized tomography (CBCT) scans. The first step was to align a hanging mirror with the vertical (XY) plane of the CBCT field-of-view (FOV) volume. Then, two scout CBCT images, at frontal and at sagittal planes, were taken when the subject exhibited a NHP. A normal CBCT scan on the subject was then taken separately. These scout images were used to correct the orientation of the normal CBCT scan. A phantom head was used for validation and performance analysis of the proposed method. It was found that the orientation detection error was within 0.88\u00b0. This enables easy and economic NHP recording for CBCT without additional hardware.<\/jats:p>","DOI":"10.3390\/s21248189","type":"journal-article","created":{"date-parts":[[2021,12,8]],"date-time":"2021-12-08T23:30:00Z","timestamp":1639006200000},"page":"8189","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Recording Natural Head Position Using Cone Beam Computerized Tomography"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7699-1937","authenticated-orcid":false,"given":"Tai-Chiu","family":"Hsung","sequence":"first","affiliation":[{"name":"Department of Computer Science, Chu Hai College of Higher Education, Tuen Mun, Hong Kong, China"},{"name":"Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3672-357X","authenticated-orcid":false,"given":"Wai-Kan","family":"Yeung","sequence":"additional","affiliation":[{"name":"Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7536-4277","authenticated-orcid":false,"given":"Wing-Shan","family":"Choi","sequence":"additional","affiliation":[{"name":"Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wai-Kuen","family":"Luk","sequence":"additional","affiliation":[{"name":"Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi-Yung","family":"Cheng","sequence":"additional","affiliation":[{"name":"Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5530-2645","authenticated-orcid":false,"given":"Yu-Hang","family":"Lam","sequence":"additional","affiliation":[{"name":"Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,12,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1016\/S2212-4268(12)60011-6","article-title":"Natural head position: Key position for radiographic and photographic analysis and research of craniofacial complex","volume":"2","author":"Verma","year":"2012","journal-title":"J. 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