{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T01:39:54Z","timestamp":1791509994543,"version":"4.3.4"},"reference-count":46,"publisher":"Oxford University Press (OUP)","issue":"2","license":[{"start":{"date-parts":[[2022,8,15]],"date-time":"2022-08-15T00:00:00Z","timestamp":1660521600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Futurum\u2014the Academy for Healthcare"},{"name":"Region J\u00f6nk\u00f6ping County"},{"name":"Malm\u00f6 University, Sweden"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2023,3,31]]},"abstract":"Summary<\/jats:title>Background<\/jats:title>Compliance is crucial for the treatment outcome with removable appliances. Previous studies on treatment with the Twin Block appliance have focused on effectiveness in relation to other treatment methods or wear-time. Studies on different check-up intervals to improve compliance seem to be lacking.<\/jats:p><\/jats:sec>Objectives<\/jats:title>To compare the impact of two different check-up prescriptions on patient compliance and treatment outcome during treatment with Twin Block.<\/jats:p><\/jats:sec>Trial Design<\/jats:title>Two-arm parallel group, single-centre, randomized controlled trial.<\/jats:p><\/jats:sec>Materials and Methods<\/jats:title>Seventy-three patients, 38 boys, and 35 girls, mean age 11.2 years, were included and block-randomized into two groups treated with a Twin Block appliance. Group 1 was called for check-up visit every sixth week and group 2 every fourth week. Compliance was evaluated with a TheraMon\u00ae microsensor, moulded into the appliance, measuring wear-time. Overjet, overbite, and molar relationships were assessed on study casts before and after treatment. The treatment outcomes were analysed on an intention-to-treat basis.<\/jats:p><\/jats:sec>Results<\/jats:title>In group 1, the reduction of overjet was 5.2 mm and the mean wear-time was 6.9 hours. In group 2, the reduction was 4.7 mm and the wear-time was 6.1 hours. Seventy-four per cent of the patients presented an overjet of 4 mm or less. Wear-time did not correlate to age, gender, or severity of malocclusion.<\/jats:p><\/jats:sec>Harms<\/jats:title>No harm was observed in any patient. Lateral open bites were registered during treatment but were normalized at the end of the treatment.<\/jats:p><\/jats:sec>Limitations<\/jats:title>The trial was a single-centre study and long-term effects were not evaluated.<\/jats:p><\/jats:sec>Conclusions<\/jats:title>During treatment with the Twin Block appliance, a 4-week check-up interval did not improve treatment outcome or increase wear-time, compared to a 6-week check-up interval. The mean wear-time was 6.5 hours per day, even if the recommendation was 12 hours.<\/jats:p><\/jats:sec>Clinical Trial Registration<\/jats:title>NCT05155774<\/jats:p><\/jats:sec>","DOI":"10.1093\/ejo\/cjac046","type":"journal-article","created":{"date-parts":[[2022,8,15]],"date-time":"2022-08-15T08:39:39Z","timestamp":1660552779000},"page":"142-149","source":"Crossref","is-referenced-by-count":14,"title":["Patient compliance with Twin Block appliance during treatment of Class II malocclusion: a randomized controlled trial on two check-up prescriptions"],"prefix":"10.1093","volume":"45","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6115-9507","authenticated-orcid":false,"given":"Erik","family":"Frilund","sequence":"first","affiliation":[{"name":"Department of Orthodontics, The Institute for Postgraduate Dental Education , J\u00f6nk\u00f6ping , Sweden"},{"name":"Centre for Oral Health, School of Health and Welfare , J\u00f6nk\u00f6ping University, J\u00f6nk\u00f6ping , Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8422-9344","authenticated-orcid":false,"given":"Mikael","family":"Sonesson","sequence":"additional","affiliation":[{"name":"Centre for Oral Health, School of Health and Welfare , J\u00f6nk\u00f6ping University, J\u00f6nk\u00f6ping , Sweden"},{"name":"Department of Orthodontics, Section 4 , University of Malm\u00f6, Malm\u00f6 , Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anders","family":"Magnusson","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, The Institute for Postgraduate Dental Education , J\u00f6nk\u00f6ping , Sweden"},{"name":"Centre for Oral Health, School of Health and Welfare , J\u00f6nk\u00f6ping University, J\u00f6nk\u00f6ping , Sweden"},{"name":"Department of Biomedical and Clinical Sciences, Link\u00f6ping University , Link\u00f6ping , Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2022,8,15]]},"reference":[{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"728","DOI":"10.2319\/080414-542.1","article-title":"Prevalence and change of malocclusions from primary to early permanent dentition: a longitudinal study","volume":"85","author":"Dimberg","year":"2015","journal-title":"The Angle Orthodontist"},{"key":"2023040102491065900_","first-page":"12","article-title":"The prevalence of malocclusion in Swedish schoolchildren","volume":"81","author":"Thilander","year":"1973","journal-title":"Scandinavian Journal of Dental Research"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"274","DOI":"10.1111\/edt.12172","article-title":"Are overweight\/obese children at risk of traumatic dental injuries? A meta-analysis of observational studies","volume":"31","author":"Corr\u00eaa-Faria","year":"2015","journal-title":"Dental Traumatology"},{"key":"2023040102491065900_","first-page":"CD003452","article-title":"Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents.","volume":"3","author":"Batista,","year":"2018","journal-title":"The Cochrane Database of Systematic Reviews"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1093\/ejo\/cjy033","article-title":"Oral health-related quality of life among children with excessive overjet or unilateral posterior crossbite with functional shift compared to children with no or mild orthodontic treatment need","volume":"41","author":"Kallunki","year":"2019","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"639","DOI":"10.1093\/ejo\/cjaa073","article-title":"Early headgear activator treatment of Class II malocclusion with excessive overjet: a randomized controlled trial","volume":"43","author":"Kallunki","year":"2021","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"621","DOI":"10.1093\/ejo\/cjv086","article-title":"A comparison of the efficacy of fixed versus removable functional appliances in children with Class II malocclusion: a systematic review","volume":"38","author":"Pacha","year":"2016","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"4861924","DOI":"10.1155\/2017\/4861924","article-title":"Comparison of activator-headgear and twin block treatment approaches in class II division 1 malocclusion","volume":"2017","author":"Spalj","year":"2017","journal-title":"Biomed Research International"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"234","DOI":"10.1016\/S0889-5406(03)00352-4","article-title":"Effectiveness of early orthodontic treatment with the Twin-block appliance: a multicenter, randomized, controlled trial. Part 1: dental and skeletal effects","volume":"124","author":"O\u2019Brien","year":"2003","journal-title":"American Journal of Orthodontics and Dentofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1093\/ejo\/cjz059","article-title":"Post-treatment cephalometric changes in adolescent patients with Class II malocclusion treated using two different functional appliance systems for an extended time period: a randomized clinical trial","volume":"4","author":"DiBiase","year":"2020","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","first-page":"187","article-title":"Treatment of malocclusions in children and adolescents at a public dental service clinic in Sweden: extent and cost","volume":"22","author":"Permert","year":"1998","journal-title":"Swedish Dental Journal"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"140","DOI":"10.1093\/ejo\/cjv026","article-title":"A cost minimization analysis of early correction of anterior crossbite\u2014a randomized controlled trial","volume":"38","author":"Wiedel","year":"2016","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1016\/j.ajodo.2018.07.016","article-title":"Effectiveness of part-time vs full-time wear protocols of Twin-block appliance on dental and skeletal changes: a randomized controlled trial","volume":"155","author":"Parekh","year":"2019","journal-title":"American Journal of Orthodontics and Dentofacial Orthopedics"},{"key":"2023040102491065900_","first-page":"114","volume-title":"Twin-Block Functional Therapy: Applications in Dentofacial Orthopaedics.","author":"Clark","year":"2002","edition":"2"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1016\/j.ajodo.2003.12.025","article-title":"Predictors for Class II treatment duration","volume":"127","author":"Popowich","year":"2005","journal-title":"American Journal of Orthodontics and Dentofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"90","DOI":"10.1590\/2177-6709.23.6.090-105.sar","article-title":"Orthodontic treatment time: can it be shortened?","volume":"23","author":"Moresca","year":"2018","journal-title":"Dental Press Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"17","DOI":"10.1016\/j.ajodo.2017.03.019","article-title":"Compliance with removable orthodontic appliances and adjuncts: a systematic review and meta-analysis","volume":"152","author":"Al-Moghrabi","year":"2017","journal-title":"American Journal of Orthodontics and Dentofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"1002","DOI":"10.2319\/010913-25.1","article-title":"Effects of wear time recording on the patient\u2019s compliance","volume":"83","author":"Pauls","year":"2013","journal-title":"The Angle Orthodontist"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"801","DOI":"10.1016\/j.ajodo.2006.01.041","article-title":"Comparing subjective and objective measures of headgear compliance","volume":"132","author":"Bos","year":"2007","journal-title":"American Journal of Orthodontics and Dentofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"239","DOI":"10.1016\/j.ajodo.2005.08.035","article-title":"Clinical and quantitative assessment of headgear compliance: a pilot study","volume":"129","author":"Brand\u00e3o","year":"2006","journal-title":"American Journal of Orthodontics and Dentofacial Orthopedics"},{"key":"2023040102491065900_","author":"MC Technology GmbH","year":"2017"},{"key":"2023040102491065900_","first-page":"i2","article-title":"Accuracy of thermosensitive microsensors intended to monitor patient use of removable oral appliances.","volume":"84","author":"Kirshenblatt","year":"2018","journal-title":"Journal of Canadian Dental Association"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1080\/14653125.2017.1365220","article-title":"How accurate are TheraMon\u00ae microsensors at measuring intraoral wear-time? Recorded vs. actual wear times in five volunteers","volume":"44","author":"Brierley","year":"2017","journal-title":"Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"56","DOI":"10.2319\/042313-315.1","article-title":"Objective assessment of patient compliance with removable orthodontic appliances: a cross-sectional cohort study","volume":"84","author":"Tsomos","year":"2014","journal-title":"The Angle Orthodontist"},{"key":"2023040102491065900_","author":"Urbaniak,","year":"2017"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1007\/s00056-011-0014-7","article-title":"Wearing times of orthodontic devices as measured by the TheraMon\u00ae microsensor","volume":"72","author":"Schott","year":"2011","journal-title":"Journal of Orofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"73","DOI":"10.1093\/ejo\/cju012","article-title":"Quantifying patient adherence during active orthodontic treatment with removable appliances using microelectronic wear-time documentation","volume":"37","author":"Sch\u00e4fer","year":"2015","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1007\/s00056-013-0143-2","article-title":"Questionnaire study of electronic wear-time tracking as experienced by patients and parents during treatment with removable orthodontic appliances","volume":"74","author":"Schott","year":"2013","journal-title":"Journal of Orofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1093\/ejo\/cjp042","article-title":"Long-term stability of dentoalveolar and skeletal changes after activator-headgear treatment","volume":"32","author":"Lerst\u00f8l","year":"2010","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","first-page":"3514","article-title":"Brief about sample size","volume":"101","author":"Ludvigsson","year":"2004","journal-title":"Lakartidningen"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1007\/s00056-010-9925-y","article-title":"Young patients\u2019 attitudes toward removable appliance wear times, wear-time instructions and electronic wear-time measurements\u2014results of a questionnaire study","volume":"71","author":"Schott","year":"2010","journal-title":"Journal of Orofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1093\/ejo\/cjaa001","article-title":"Treatment compliance of adolescent orthodontic patients with headgear activator and twin-block appliance assessed prospectively using microelectronic wear-time documentation","volume":"42","author":"Arponen","year":"2020","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"378","DOI":"10.1016\/S0889-5406(05)81337-X","article-title":"Correlates of objective patient compliance with removable appliance wear","volume":"104","author":"Bartsch","year":"1993","journal-title":"American Journal of Orthodontics and Dentofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"53","DOI":"10.1007\/BF00844768","article-title":"Cooperation of adolescents in orthodontic treatment","volume":"14","author":"Albino","year":"1991","journal-title":"Journal of Behavioral Medicine"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"289","DOI":"10.1093\/ejo\/26.3.289","article-title":"The role of the headgear timer in extraoral co-operation","volume":"26","author":"Doruk","year":"2004","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"173","DOI":"10.1016\/j.ajodo.2018.06.011","article-title":"Understanding factors influencing compliance with removable functional appliances: a qualitative study","volume":"155","author":"El-Huni","year":"2019","journal-title":"American Journal of Orthodontics and Dentofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"238","DOI":"10.1093\/ejo\/cju046","article-title":"The impact of malocclusion on the quality of life among children and adolescents: a systematic review of quantitative studies","volume":"37","author":"Dimberg","year":"2015","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"88","DOI":"10.2319\/020616-104.1","article-title":"Objective assessment of compliance with intra- and extraoral removable appliances","volume":"87","author":"Arreghini","year":"2017","journal-title":"The Angle Orthodontist"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"386","DOI":"10.1093\/ejo\/cjn018","article-title":"Factors affecting the duration of orthodontic treatment: a systematic review","volume":"30","author":"Mavreas","year":"2008","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"143","DOI":"10.1016\/0889-5406(87)90472-0","article-title":"Treatment with an orthopedic appliance system in relation to treatment intensity and growth periods. A study of initial effects","volume":"91","author":"Malmgren","year":"1987","journal-title":"American Journal of Orthodontics and Dentofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"335","DOI":"10.1067\/mod.2000.107009","article-title":"Mandibular growth as related to cervical vertebral maturation and body height.","volume":"118","author":"Franchi","year":"2000","journal-title":"American Journal of Orthodontics and Dentofacial Orthopedics"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"1271","DOI":"10.1016\/j.jclinepi.2013.05.016","article-title":"Single-center trials tend to provide larger treatment effects than multicenter trials: a systematic review","volume":"66","author":"Unverzagt","year":"2013","journal-title":"Journal of Clinical Epidemiology"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"267","DOI":"10.1016\/j.jclinepi.2013.08.015","article-title":"Systematic review of the Hawthorne effect: new concepts are needed to study research participation effects","volume":"67","author":"McCambridge","year":"2014","journal-title":"Journal of Clinical Epidemiology"},{"key":"2023040102491065900_","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1093\/ejo\/cjx089","article-title":"Hawthorne effect reporting in orthodontic randomized controlled trials: truth or myth? Blessing or curse?","volume":"40","author":"Abdulraheem","year":"2018","journal-title":"European Journal of Orthodontics"},{"key":"2023040102491065900_","author":"Emergency information from the Swedish Authorities","year":"2020"},{"key":"2023040102491065900_","article-title":"Effekter av covid-19 p\u00e5 tandv\u00e5rdsbes\u00f6k bland barn och vuxna - del 3","author":"Socialstyrelsen","year":"2021","journal-title":"The Swedish Social Services"}],"container-title":["European Journal of Orthodontics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/academic.oup.com\/ejo\/article-pdf\/45\/2\/142\/49718416\/cjac046.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/ejo\/article-pdf\/45\/2\/142\/49718416\/cjac046.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,11,25]],"date-time":"2023-11-25T19:54:07Z","timestamp":1700942047000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/ejo\/article\/45\/2\/142\/6667522"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,8,15]]},"references-count":46,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2022,8,15]]},"published-print":{"date-parts":[[2023,3,31]]}},"URL":"https:\/\/doi.org\/10.1093\/ejo\/cjac046","relation":{},"ISSN":["0141-5387","1460-2210"],"issn-type":[{"value":"0141-5387","type":"print"},{"value":"1460-2210","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2023,4,1]]},"published":{"date-parts":[[2022,8,15]]}}}