{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T03:04:32Z","timestamp":1771211072435,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2020,5,7]],"date-time":"2020-05-07T00:00:00Z","timestamp":1588809600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Dentistry Journal"],"abstract":"<jats:p>This study aimed to evaluate and compare the dentoalveolar effects of the myofunctional trainer T4KTM versus twin block in children with class II division I malocclusion. Two parallel arm randomized comparative clinical trial was conducted, including twenty healthy children, 9\u201312 years old, showing Angle\u2019s class II division I malocclusion due to mandibular retrusion. Children were randomly assigned into two groups according to the appliance used; Group 1: T4k, and Group II: twin block. Follow-up was done every 4 weeks for 9 months. Postoperative cephalometric X ray, study casts and photographs were taken for measurements and comparison. T4K showed a statistically significant reduction in the overjet (\u22122.50 \u00b1 1.00 mm) (p &lt; 0.0001), and a significant increase in the lower arch perimeter (LAP) (1.19 \u00b1 0.96 mm) (p = 0.01). The twin block showed a statistically significant reduction in the overjet (\u22123.75 \u00b1 1.10 mm) (p &lt; 0.0001), a significant reduction in the overbite (\u221216.22 \u00b1 17.02 %) (p = 0.03), and a significant increase in the LAP (1.69 \u00b1 0.70 mm) (p &lt; 0.0001). The overjet showed a higher significant decrease in the twin block group than in T4K (p = 0.03). The mean values of the overbite were significantly decreased in twin block than in T4k (p &lt; 0.0001). Both groups showed significant dentoalveolar improvements toward class I occlusion; however, the twin block showed significantly better results than T4K appliance.<\/jats:p>","DOI":"10.3390\/dj8020044","type":"journal-article","created":{"date-parts":[[2020,5,8]],"date-time":"2020-05-08T03:45:20Z","timestamp":1588909520000},"page":"44","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Myofunctional Trainer versus Twin Block in Developing Class II Division I Malocclusion: A Randomized Comparative Clinical Trial"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5464-1968","authenticated-orcid":false,"given":"Yasmine","family":"Elhamouly","sequence":"first","affiliation":[{"name":"Pediatric Dentistry and Oral Public Health Department, Faculty of Dentistry, Alexandria University, Alexandria 21526, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8087-758X","authenticated-orcid":false,"given":"Azza A.","family":"El-Housseiny","sequence":"additional","affiliation":[{"name":"Pediatric Dentistry and Oral Public Health Department, Faculty of Dentistry, Alexandria University, Alexandria 21526, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hanan A.","family":"Ismail","sequence":"additional","affiliation":[{"name":"Orthodontic Department, Faculty of Dentistry, Alexandria University, Alexandria 21526, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9812-6247","authenticated-orcid":false,"given":"Laila M.","family":"El Habashy","sequence":"additional","affiliation":[{"name":"Pediatric Dentistry and Oral Public Health Department, Faculty of Dentistry, Alexandria University, Alexandria 21526, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"477","DOI":"10.1016\/0002-9416(80)90299-7","article-title":"Differential diagnosis of Class II malocclusions: Part 1. 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