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The OHIP-14 score, self-reported chronic illness, temporomandibular disorder (TMD pain) and subjective orthodontic treatment need were compared between 98 extremely and very preterm born (&lt;\u200932 gestational week) and 93 full-term controls (\u2265\u200937 gestational week) at two ages. The chi-square test was used for comparisons within the extremely-, very-, and full-term control groups, and to contrast the differences of mean scores of OHIP-14, the ANOVA test was used for comparisons within the study groups of extremely preterm, very preterm and full term-born adolescents.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Results<\/jats:title>\n                <jats:p>All adolescents reported a good self-perceived OHRQoL. No significant differences in the comparisons of the total mean scores were revealed between the groups, between gender or in domain-specific scores over the 5-year period. Very preterm adolescents with reported chronic illness at 12\u201314\u00a0years of age showed significantly higher mean scores of OHIP-14 compared with those without chronic illness (<jats:italic>p<\/jats:italic>\u2009=\u2009<jats:italic>0.015<\/jats:italic>). At age 17\u201319, significantly higher mean scores of OHIP-14 were reported by very preterm adolescents with TMD pain compared to those without TMD pain (<jats:italic>p<\/jats:italic>\u2009=\u2009<jats:italic>0.024<\/jats:italic>). Significantly higher mean scores of OHIP-14 were found among the extremely preterm (<jats:italic>p<\/jats:italic>\u2009=\u2009<jats:italic>0.011<\/jats:italic>) and very preterm born adolescents (<jats:italic>p<\/jats:italic>\u2009=\u2009<jats:italic>0.031<\/jats:italic>) with a subjective need of orthodontic treatment compared with those without orthodontic treatment need.<\/jats:p>\n              <\/jats:sec><jats:sec>\n                <jats:title>Conclusions<\/jats:title>\n                <jats:p>Poor OHRQoL measured with OHIP-14 in very preterm adolescents aged 12\u201314 was related to chronic illness and aged 17\u201319 to TMD pain. In addition, extremely and very preterm-born adolescents with subjective orthodontic treatment need at 17\u201319\u00a0years of age also reported poor OHRQoL. To improve the dentist\u2013patient relationship and achieve more successful treatment results, it is important for dental clinicians to understand the impact that chronic illness, TMD pain and orthodontic treatment need has on OHRQoL in preterm-born adolescents.<\/jats:p>\n              <\/jats:sec>","DOI":"10.1186\/s12903-021-01799-3","type":"journal-article","created":{"date-parts":[[2021,9,9]],"date-time":"2021-09-09T14:06:45Z","timestamp":1631196405000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Do preterm-born adolescents have a poorer oral health-related quality of life?"],"prefix":"10.1186","volume":"21","author":[{"given":"Susanne","family":"Brog\u00e5rdh-Roth","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Liselotte","family":"Paulsson","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pernilla","family":"Larsson","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ewacarin","family":"Ekberg","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2021,9,9]]},"reference":[{"key":"1799_CR1","doi-asserted-by":"publisher","first-page":"1409","DOI":"10.1111\/apa.13880","volume":"106","author":"TNK Raju","year":"2017","unstructured":"Raju TNK, Buist AS, Blaisdell CJ, Moxey-Mims M, Saigal S. 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Written information regarding the study was sent to the adolescents and their parents, including information about confidential and voluntary participation, and the right to discontinue participation at any time. A written informed consent form was attached along with the questionnaires to request all the parents\u2019 and the adolescents\u2019 consent. The questionnaire with a reminder was sent out twice, and a further reminder was conducted by telephone. All methods were performed in accordance with the relevant guidelines and regulations.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"440"}}