{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T18:55:54Z","timestamp":1787943354246,"version":"build-2784847793"},"reference-count":27,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,6,6]],"date-time":"2021-06-06T00:00:00Z","timestamp":1622937600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Children"],"abstract":"<jats:p>The ectopic eruption of the maxillary first permanent molar (EEM) is a local alteration of dental eruption with a multifactorial aetiology. The aims of our study were to determine the prevalence of the EEM in children and to analyse whether there is a relationship between EEM and dento-skeletal characteristics. A total of 322 children were analysed with the Ricketts cephalometric study and descriptive and analytical statistical analysis was carried out. The prevalence of EEM was 8.7%, with no statistically significant differences regarding gender or location, but a higher prevalence in the 7-year-old age group (18.8%) and bilateral EEM was more prevalent than unilateral EEM (p &lt; 0.05). The most frequent findings were a shortened anterior cranial base, a retroposition of the maxilla and a distal position of the upper permanent first molar in relation to the pterygoid vertical in children with EEM. No statistically significant differences were found regarding the cephalometric parameters except a decreased palatal plane in the bilateral EEM group and a distal upper incisor position in the EEM group (p &lt; 0.05). In conclusion, the prevalence of the EEM was 8.7%, more frequently bilateral, and significantly in seven-year-old patients. Children with bilateral EEM have decreased palatal plane values and a more posterior position of the upper incisor.<\/jats:p>","DOI":"10.3390\/children8060479","type":"journal-article","created":{"date-parts":[[2021,6,6]],"date-time":"2021-06-06T23:59:55Z","timestamp":1623023995000},"page":"479","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Ectopic Eruption of Maxillary First Permanent Molars: Preliminary Results of Prevalence and Dentoskeletal Characteristics in Spanish Paediatric Population"],"prefix":"10.3390","volume":"8","author":[{"given":"Alexandra","family":"Helm","sequence":"first","affiliation":[{"name":"Department of Dental Clinical Specialties, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain"},{"name":"Eastman Dental Institute, University College London, London 28040, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0489-2256","authenticated-orcid":false,"given":"Andrea","family":"Mart\u00edn-Vacas","sequence":"additional","affiliation":[{"name":"Department of Dental Clinical Specialties, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain"},{"name":"University Dental Clinic, \u201cAlfonso X El Sabio\u201d University, 28037 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5493-0295","authenticated-orcid":false,"given":"Pedro","family":"Molinero-Mourelle","sequence":"additional","affiliation":[{"name":"Department of Conservative Dentistry and Orofacial Prosthodontics, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain"},{"name":"Department of Reconstructive Dentistry and Gerodontology, School of Dental Medicine, University of Bern, 3010 Bern, Switzerland"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Antonia M.","family":"Caleya","sequence":"additional","affiliation":[{"name":"Department of Dental Clinical Specialties, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nuria E.","family":"Gallardo","sequence":"additional","affiliation":[{"name":"Department of Dental Clinical Specialties, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mar\u00eda Rosa","family":"Mourelle-Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Department of Dental Clinical Specialties, Faculty of Dentistry, Complutense University of Madrid, 28040 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,6]]},"reference":[{"key":"ref_1","first-page":"153","article-title":"Ectopic eruption of the first permanent molar","volume":"24","author":"Young","year":"1957","journal-title":"J. Dent. Child."},{"key":"ref_2","first-page":"408","article-title":"Correction of ectopic eruption of permanent molars utilizing the brass wire technique","volume":"22","author":"Kupietzky","year":"2000","journal-title":"Pediatr. Dent."},{"key":"ref_3","first-page":"7","article-title":"A review of the eruption of primary teeth","volume":"2","author":"Yeung","year":"2014","journal-title":"OA Dent."},{"key":"ref_4","first-page":"179","article-title":"Ectopic eruption of the first permanent maxillary molar in cleft lip and cleft palate children","volume":"32","author":"Ge","year":"1965","journal-title":"J. Dent. Child."},{"key":"ref_5","first-page":"29","article-title":"Prevalence of ectopic eruption of the maxillary first permanent molar","volume":"5","author":"Bjerklin","year":"1981","journal-title":"Swed Dent. J."},{"key":"ref_6","first-page":"273","article-title":"Resorption of maxillary second primary molars caused by ectopic eruption of the maxillary first permanent molar: A longitudinal and histological study","volume":"49","author":"Kurol","year":"1982","journal-title":"ASDC J. Dent. Child."},{"key":"ref_7","first-page":"153","article-title":"Ectopic eruption of the first permanent molars: Prevalence and etiologic factors","volume":"68","author":"Chintakanon","year":"1998","journal-title":"Angle Orthod."},{"key":"ref_8","first-page":"294","article-title":"Ectopic eruption of maxillary first permanent molars in different areas of the United States","volume":"49","author":"Kimmel","year":"1982","journal-title":"ASDC J. Dent. Child."},{"key":"ref_9","first-page":"138","article-title":"The etiology and prevalence of ectopic eruption of the maxillary first permanent molar","volume":"35","author":"Pulver","year":"1968","journal-title":"ASDC J. Dent. Child."},{"key":"ref_10","first-page":"339","article-title":"First upper permanent molars partially impacted against second deciduous molars","volume":"9","author":"Chapman","year":"1923","journal-title":"Int. J. Ortho. Oral Surg. Radio."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"774","DOI":"10.14219\/jada.archive.1947.0391","article-title":"Impaction of permanent first molar with resorption and space loss in region of deciduous second molar","volume":"35","author":"Cheyne","year":"1947","journal-title":"J. Am. Dent. Assoc."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1016\/0002-9416(83)90179-3","article-title":"Ectopic eruption of the maxillary first permanent molar: Etiologic factors","volume":"84","author":"Bjerklin","year":"1983","journal-title":"Am. J. Orthod."},{"key":"ref_13","unstructured":"Salzmann, J.A. (1957). Orthodontics: Principles and Prevention, Lippincott."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1016\/S0011-8532(22)02264-9","article-title":"Treatment of ectopically erupting permanent molars","volume":"28","author":"Harrison","year":"1984","journal-title":"Dent. Clin. N. Am."},{"key":"ref_15","first-page":"447","article-title":"Ectopic eruption of the maxillary permanent first molar: The effect of increased mesial angulation on arch length","volume":"111","author":"Yuen","year":"1985","journal-title":"JADA (1939)"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"249","DOI":"10.1093\/ejo\/5.3.249","article-title":"Morphological analysis of cases with ectopic eruption of the maxillary first permanent molar","volume":"5","author":"Canut","year":"1983","journal-title":"Eur. J. Orthod."},{"key":"ref_17","first-page":"141","article-title":"Cephalometric analysis and synthesis","volume":"31","author":"Ricketts","year":"1961","journal-title":"Angle Orthod."},{"key":"ref_18","first-page":"209","article-title":"Ectopic eruption of maxillary first permanent molars: A review","volume":"53","author":"Kurol","year":"1986","journal-title":"ASDC J. Dent. Child."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"190","DOI":"10.4041\/kjod.2015.45.4.190","article-title":"Dentoskeletal features in individuals with ectopic eruption of the permanent maxillary first molar","volume":"45","author":"Mucedero","year":"2015","journal-title":"Korean J. Orthod."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"147","DOI":"10.5933\/JKAPD.2017.44.2.147","article-title":"Association between Ectopic Eruption of the Maxillary First Permanent Molar and Skeletal Malocclusion","volume":"44","author":"Rah","year":"2017","journal-title":"J. Korean Acad. Pediatr. Dent."},{"key":"ref_21","first-page":"610","article-title":"Ectopic eruption of the maxillary first permanent molar: Characteristics and occurrence in growing children","volume":"75","year":"2005","journal-title":"Angle Orthod."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1177\/00220345620410031301","article-title":"Ectopic eruption pattern in selected permanent teeth","volume":"41","year":"1962","journal-title":"J. Dent. Res."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"574","DOI":"10.14219\/jada.archive.1939.0136","article-title":"Ectopic eruption of permanent teeth","volume":"26","author":"Sweet","year":"1939","journal-title":"J. Am. Dent. Assoc."},{"key":"ref_24","first-page":"270","article-title":"Ectopic Eruption of Teeth","volume":"23","author":"Lower","year":"1960","journal-title":"Chron. Omaha. Dist. D. Soc."},{"key":"ref_25","first-page":"241","article-title":"Ectopic Eruption","volume":"25","author":"Niliforuk","year":"1948","journal-title":"J. Ontario DA"},{"key":"ref_26","first-page":"30","article-title":"The face in profile","volume":"40","author":"Bjork","year":"1947","journal-title":"Sven. Tidskr."},{"key":"ref_27","unstructured":"Solow, B. (1966). The pattern of craniofacial associations. Acta Odontol. Scand., 24."}],"container-title":["Children"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2227-9067\/8\/6\/479\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:11:23Z","timestamp":1760163083000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2227-9067\/8\/6\/479"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,6]]},"references-count":27,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2021,6]]}},"alternative-id":["children8060479"],"URL":"https:\/\/doi.org\/10.3390\/children8060479","relation":{},"ISSN":["2227-9067"],"issn-type":[{"value":"2227-9067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,6,6]]}}}