{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T20:59:40Z","timestamp":1777496380123,"version":"3.51.4"},"reference-count":39,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2021,6,29]],"date-time":"2021-06-29T00:00:00Z","timestamp":1624924800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Background: To compare the skeletal, dental, and esthetic changes produced by three functional devices, Fr\u00e4nkel-2 appliance (FR-2), Twin Block (TB), and Occlus-o-Guide\u00ae (O-o-G\u00ae), for the treatment of Class II malocclusion. Methods: Sixty-five patients with Class II Division 1 malocclusion were divided into three groups and were analyzed through cephalometric analysis of skeletal, dental, and esthetic variables before and after treatment. The first group of 23 patients (F: 9; M: 14; mean age: 10.3 \u00b1 1.08 years) was treated with FR-2, the second group of 18 patients (F: 8; M: 10; mean age 10.7 \u00b1 1.05 years) was treated with TB, the third group (F: 11; M: 13; mean age: 9.05 \u00b1 0.39 years) of 24 patients was treated with O-o-G\u00ae. The structural effects of the three devices were compared with a control group generated by the growth variations reported in the cephalometric atlas of Bhatia and Leighton. Esthetic analysis was performed comparing the results of the patients treated with a control group of 20 subjects with mandibular retrognathia and Class II Division 1 malocclusion, not subjected to therapy. Results: The three devices resulted in a significant increase in mandibular length, with higher results obtained for FR-2 and TB. A statistically significant increase in the IMPA angle was found for the O-o-G\u00ae group, and a notable reduction of both overjet and overbite was detected in all three groups of treated patients. The esthetic evaluation showed overall more significant results in the TB group, especially with regard to the reduction of facial convexity. The retrusion of the upper lip was on average more significant in the O-o-G\u00ae group, followed by that in the TB. Conclusions: All three devices have proven to be effective overall in resolving skeletal changes and improving facial esthetics.<\/jats:p>","DOI":"10.3390\/ijerph18136978","type":"journal-article","created":{"date-parts":[[2021,6,29]],"date-time":"2021-06-29T10:52:46Z","timestamp":1624963966000},"page":"6978","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Comparative Evaluation of Esthetic and Structural Aspects in Class II Functional Therapy. A Case\u2013Control Retrospective Study"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6876-8839","authenticated-orcid":false,"given":"Gabriella","family":"Galluccio","sequence":"first","affiliation":[{"name":"Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0497-5991","authenticated-orcid":false,"given":"Rosanna","family":"Guarnieri","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Diana","family":"Jamshir","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0660-4062","authenticated-orcid":false,"given":"Alessandra","family":"Impellizzeri","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gaetano","family":"Ierardo","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ersilia","family":"Barbato","sequence":"additional","affiliation":[{"name":"Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, 00161 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"631","DOI":"10.5005\/jp-journals-10024-2570","article-title":"Epidemiology of Malocclusion in 3491 Subjects Attending Public Dental Service in Rome (Italy): Evaluation of the Orthodontic Treatment Need Index","volume":"20","author":"Giordano","year":"2019","journal-title":"J. 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