{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,20]],"date-time":"2026-03-20T08:13:39Z","timestamp":1773994419522,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,10,20]],"date-time":"2025-10-20T00:00:00Z","timestamp":1760918400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Health & Welfare, Republic of Korea","award":["RS-2025-02293109"],"award-info":[{"award-number":["RS-2025-02293109"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>Background: Prefabricated functional appliances (PFAs) are widely used for interceptive orthodontic treatment in children, delivering intermittent forces with potential advantages for oral function. This study evaluated the effects of PFA treatment on the root development of maxillary central incisors in children during the mixed dentition stage using panoramic radiographs. Methods: A retrospective review was conducted on 77 children in the mixed dentition phase (2020\u20132025). These were divided into three groups: untreated controls (n = 33); skeletal Class II malocclusion group, treated with the Pre-Ortho\u00ae Type 1 appliance (Group 1, n = 25); and functional anterior crossbite group treated with a Type 3 appliance (Group 2, n = 19). All participants underwent at least two panoramic radiographs; treatment was initiated when the maxillary central incisors were at Nolla stages 8 or 9. Following root completion, panoramic images were analyzed using the modified Lind method to measure crown length, root length, and root-to-crown ratio. Results: Mean final root lengths of the maxillary central incisors were 14.11 \u00b1 1.40 mm (controls), 14.46 \u00b1 1.42 mm (Group 1), and 13.89 \u00b1 1.04 mm (Group 2) (p &gt; 0.05). The mean root\u2013crown ratios showed no significant variation (p &gt; 0.05). Root development was unaffected by wear duration, with limited sex differences. Conclusions: PFA treatment may not adversely affect the root development of maxillary central incisors and indicates a safe intervention in children.<\/jats:p>","DOI":"10.3390\/children12101416","type":"journal-article","created":{"date-parts":[[2025,10,20]],"date-time":"2025-10-20T10:44:10Z","timestamp":1760957050000},"page":"1416","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Panoramic Assessment of Root Development in Immature Maxillary Incisors After Treatment with Prefabricated Functional Appliances"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-1489-5941","authenticated-orcid":false,"given":"Wonbin","family":"Seo","sequence":"first","affiliation":[{"name":"Department of Pediatric Dentistry, Dental Research Institute, Pusan National University Dental Hospital, Yangsan 50612, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3264-4014","authenticated-orcid":false,"given":"Soyoung","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Pediatric Dentistry, Dental Research Institute, Pusan National University Dental Hospital, Yangsan 50612, Republic of Korea"},{"name":"Department of Pediatric Dentistry, School of Dentistry, Dental and Life Science Institute, Pusan National University, Yangsan 50612, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8313-8571","authenticated-orcid":false,"given":"Eungyung","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Pediatric Dentistry, Dental Research Institute, Pusan National University Dental Hospital, Yangsan 50612, Republic of Korea"},{"name":"Department of Pediatric Dentistry, School of Dentistry, Dental and Life Science Institute, Pusan National University, Yangsan 50612, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0431-5574","authenticated-orcid":false,"given":"Taesung","family":"Jeong","sequence":"additional","affiliation":[{"name":"Department of Pediatric Dentistry, Dental Research Institute, Pusan National University Dental Hospital, Yangsan 50612, Republic of Korea"},{"name":"Department of Pediatric Dentistry, School of Dentistry, Dental and Life Science Institute, Pusan National University, Yangsan 50612, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9777-0196","authenticated-orcid":false,"given":"Jonghyun","family":"Shin","sequence":"additional","affiliation":[{"name":"Department of Pediatric Dentistry, Dental Research Institute, Pusan National University Dental Hospital, Yangsan 50612, Republic of Korea"},{"name":"Department of Pediatric Dentistry, School of Dentistry, Dental and Life Science Institute, Pusan National University, Yangsan 50612, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,20]]},"reference":[{"key":"ref_1","first-page":"1","article-title":"2 \u00d7 4 appliance in the mixed dentition stage: A scoping review of the evidence","volume":"47","year":"2023","journal-title":"J. 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