{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,30]],"date-time":"2026-10-30T14:35:20Z","timestamp":1793370920343,"version":"4.5.0"},"reference-count":41,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,3,13]],"date-time":"2026-03-13T00:00:00Z","timestamp":1773360000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T00:00:00Z","timestamp":1775692800000},"content-version":"vor","delay-in-days":27,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100002386","name":"Cairo University","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100002386","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["BMC Oral Health"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To quantify space loss following premature extraction of primary first molars (Ds) over a follow-up period of at least six months and evaluate its clinical implications.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Materials and methods<\/jats:title>\n                    <jats:p>A systematic search of PubMed, Cochrane Library, LILACS, Web of Science, and Embase was conducted. Only longitudinal split-mouth cohort studies were included. The primary outcome was the amount of space loss in the extraction region, measured against the contralateral control side.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      7 studies were included, comprising 141 children for maxillary analysis and 171 children for mandibular analysis. Meta-analysis for space loss revealed a mean difference (MD) of -0.52\u00a0mm (95% CI: -0.79 to -0.26;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001) in the maxilla after 9\u201312 months, and \u2212\u20091.78\u00a0mm (95% CI: -2.09 to -1.47;\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&lt;\u20090.001) in the mandible after 8\u20139 months.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Premature loss of Ds in children aged 6\u20139 years results in space loss of -0.52\u00a0mm in the maxilla and \u2212\u20091.78\u00a0mm in the mandible. Space maintainers are indicated following mandibular extractions, while maxillary cases may not require routine intervention.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s12903-026-07934-2","type":"journal-article","created":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T23:44:05Z","timestamp":1773359045000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Extraction of first primary molars and significance of space loss: a systematic review and meta-analysis"],"prefix":"10.1186","volume":"26","author":[{"given":"Ahmed Kamal","family":"El-Motayam","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mostafa A.","family":"Hassan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mais Medhat","family":"Sadek","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rim","family":"Fathalla","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nour","family":"Wahba","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Reem","family":"Mahmoud","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shereen Hassan","family":"Elshamy","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,3,13]]},"reference":[{"issue":"4","key":"7934_CR1","doi-asserted-by":"publisher","first-page":"100816","DOI":"10.1016\/j.ortho.2023.100816","volume":"21","author":"P Shakti","year":"2023","unstructured":"Shakti P, Singh A, Purohit BM, Purohit A, Taneja S. Effect of premature loss of primary teeth on prevalence of malocclusion in permanent dentition: a systematic review and meta-analysis. Int Orthod. 2023;21(4):100816.","journal-title":"Int Orthod"},{"issue":"6","key":"7934_CR2","doi-asserted-by":"publisher","first-page":"423","DOI":"10.1007\/s40368-016-0247-7","volume":"17","author":"N Bhujel","year":"2016","unstructured":"Bhujel N, Duggal MS, Saini P, Day PF. The effect of premature extraction of primary teeth on the subsequent need for orthodontic treatment. Eur Arch Paediatr Dent. 2016;17(6):423\u201334.","journal-title":"Eur Arch Paediatr Dent"},{"key":"7934_CR3","doi-asserted-by":"publisher","first-page":"420","DOI":"10.5114\/jos.2018.84765","volume":"71","author":"M Gibas-Stanek","year":"2018","unstructured":"Gibas-Stanek M, Loster B. The effect of premature extraction of primary molars on spatial conditions and formation of malocclusion \u2013 a systematic review. J Stomatol. 2018;71:420\u201331.","journal-title":"J Stomatol"},{"issue":"6","key":"7934_CR4","doi-asserted-by":"publisher","first-page":"771","DOI":"10.1016\/j.ajodo.2011.04.023","volume":"140","author":"MC Macena","year":"2011","unstructured":"Macena MC, Tornisiello Katz CR, Heimer MV, de Oliveira e Silva JF, Costa LB. Space changes after premature loss of deciduous molars among Brazilian children. Am J Orthod Dentofac Orthop. 2011;140(6):771\u20138.","journal-title":"Am J Orthod Dentofac Orthop"},{"issue":"4","key":"7934_CR5","first-page":"295","volume":"54","author":"WM Northway","year":"1984","unstructured":"Northway WM, Wainright RL, Demirjian A. Effects of premature loss of deciduous molars. Angle Orthod. 1984;54(4):295\u2013329.","journal-title":"Angle Orthod"},{"key":"7934_CR6","first-page":"2","volume":"20","author":"S Kronfeld","year":"1953","unstructured":"Kronfeld S. The effects of premature loss of primary teeth and sequence of eruption of permanent teeth on malocclusion. J Dent Child. 1953;20:2\u20133.","journal-title":"J Dent Child"},{"issue":"10","key":"7934_CR7","first-page":"753","volume":"63","author":"DJ Brothwell","year":"1997","unstructured":"Brothwell DJ. Guidelines on the use of space maintainers following premature loss of primary teeth. J Can Dent Assoc. 1997;63(10):753. 757\u2009\u2013\u200960, 764-6.","journal-title":"J Can Dent Assoc"},{"issue":"4","key":"7934_CR8","first-page":"177","volume":"33","author":"HN Nance","year":"1947","unstructured":"Nance HN. The limitations of orthodontic treatment; mixed dentition diagnosis and treatment. Am J Orthod. 1947;33(4):177\u2013223.","journal-title":"Am J Orthod"},{"issue":"4","key":"7934_CR9","first-page":"297","volume":"30","author":"W Tunison","year":"2008","unstructured":"Tunison W, Flores-Mir C, ElBadrawy H, Nassar U, El-Bialy T. Dental arch space changes following premature loss of primary first molars: a systematic review. Pediatr Dent. 2008;30(4):297\u2013302.","journal-title":"Pediatr Dent"},{"issue":"3","key":"7934_CR10","doi-asserted-by":"publisher","first-page":"364","DOI":"10.1007\/s10266-016-0281-2","volume":"105","author":"EG Kaklamanos","year":"2017","unstructured":"Kaklamanos EG, Lazaridou D, Tsiantou D, Kotsanos N, Athanasiou AE. Dental arch spatial changes after premature loss of first primary molars: a systematic review of controlled studies. Odontology. 2017;105(3):364\u201374.","journal-title":"Odontology"},{"issue":"1","key":"7934_CR11","doi-asserted-by":"publisher","first-page":"430","DOI":"10.1186\/s12903-023-03111-x","volume":"23","author":"J Zhao","year":"2023","unstructured":"Zhao J, Jin H, Li X, Qin X. Dental arch spatial changes after premature loss of first primary molars: a systematic review and meta-analysis of split-mouth studies. BMC Oral Health. 2023;23(1):430.","journal-title":"BMC Oral Health"},{"key":"7934_CR12","doi-asserted-by":"publisher","first-page":"n71","DOI":"10.1136\/bmj.n71","volume":"372","author":"MJ Page","year":"2021","unstructured":"Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, Shamseer L, Tetzlaff JM, Akl EA, Brennan SE, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ. 2021;372:n71.","journal-title":"BMJ"},{"issue":"4","key":"7934_CR13","doi-asserted-by":"publisher","first-page":"344","DOI":"10.1016\/j.jclinepi.2007.11.008","volume":"61","author":"E von Elm","year":"2008","unstructured":"von Elm E, Altman DG, Egger M, Pocock SJ, G\u00f8tzsche PC, Vandenbroucke JP. The Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: guidelines for reporting observational studies. J Clin Epidemiol. 2008;61(4):344\u20139.","journal-title":"J Clin Epidemiol"},{"key":"7934_CR14","volume-title":"Cochrane handbook for systematic reviews of interventions","year":"2019","unstructured":"Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, et al. editors. Cochrane handbook for systematic reviews of interventions. 2nd ed. Chichester (UK): Wiley; 2019.","edition":"2"},{"key":"7934_CR15","doi-asserted-by":"publisher","first-page":"i4919","DOI":"10.1136\/bmj.i4919","volume":"355","author":"JA Sterne","year":"2016","unstructured":"Sterne JA, Hern\u00e1n MA, Reeves BC, Savovi\u0107 J, Berkman ND, Viswanathan M, Henry D, Altman DG, Ansari MT, Boutron I, et al. ROBINS-I: a tool for assessing risk of bias in non-randomised studies of interventions. BMJ. 2016;355:i4919.","journal-title":"BMJ"},{"issue":"1","key":"7934_CR16","doi-asserted-by":"publisher","first-page":"44","DOI":"10.1016\/j.jds.2016.06.005","volume":"12","author":"YJ Lin","year":"2017","unstructured":"Lin YJ, Lin YT. Long-term space changes after premature loss of a primary maxillary first molar. J Dent Sci. 2017;12(1):44\u20138.","journal-title":"J Dent Sci"},{"issue":"3","key":"7934_CR17","doi-asserted-by":"publisher","first-page":"362","DOI":"10.14219\/jada.archive.2007.0169","volume":"138","author":"YT Lin","year":"2007","unstructured":"Lin YT, Lin WH, Lin YT. Immediate and six-month space changes after premature loss of a primary maxillary first molar. J Am Dent Assoc. 2007;138(3):362\u20138.","journal-title":"J Am Dent Assoc"},{"issue":"12","key":"7934_CR18","doi-asserted-by":"publisher","first-page":"1711","DOI":"10.14219\/jada.archive.2000.0117","volume":"131","author":"WM Northway","year":"2000","unstructured":"Northway WM. The not-so-harmless maxillary primary first molar extraction. J Am Dent Assoc. 2000;131(12):1711\u201320.","journal-title":"J Am Dent Assoc"},{"issue":"2","key":"7934_CR19","doi-asserted-by":"publisher","first-page":"218","DOI":"10.2319\/030714-160.1","volume":"85","author":"SA Alexander","year":"2015","unstructured":"Alexander SA, Askari M, Lewis P. The premature loss of primary first molars: space loss to molar occlusal relationships and facial patterns. Angle Orthod. 2015;85(2):218\u201323.","journal-title":"Angle Orthod"},{"issue":"3","key":"7934_CR20","doi-asserted-by":"publisher","first-page":"161","DOI":"10.1111\/j.1365-263X.2010.01105.x","volume":"21","author":"YT Lin","year":"2011","unstructured":"Lin YT, Lin WH, Lin YT. Twelve-month space changes after premature loss of a primary maxillary first molar. Int J Paediatr Dent. 2011;21(3):161\u20136.","journal-title":"Int J Paediatr Dent"},{"issue":"4","key":"7934_CR21","first-page":"311","volume":"22","author":"YT Lin","year":"1998","unstructured":"Lin YT, Chang LC. Space changes after premature loss of the mandibular primary first molar: a longitudinal study. J Clin Pediatr Dent. 1998;22(4):311\u20136.","journal-title":"J Clin Pediatr Dent"},{"issue":"3","key":"7934_CR22","doi-asserted-by":"publisher","first-page":"226","DOI":"10.4103\/jisppd.jisppd_86_24","volume":"42","author":"R Kundra","year":"2024","unstructured":"Kundra R, Sharma D, Kaur R, Monga S, Duvedi S. Spatial and angular alterations in the dental arch after premature loss of primary molars: immediate and 9-month computed tomography evaluation. J Indian Soc Pedod Prev Dent. 2024;42(3):226\u201334.","journal-title":"J Indian Soc Pedod Prev Dent"},{"issue":"2","key":"7934_CR23","doi-asserted-by":"publisher","first-page":"90","DOI":"10.4103\/0970-4388.26023","volume":"24","author":"B Padma Kumari","year":"2006","unstructured":"Padma Kumari B, Retnakumari N. Loss of space and changes in the dental arch after premature loss of the lower primary molar: a longitudinal study. J Indian Soc Pedod Prev Dent. 2006;24(2):90\u20136.","journal-title":"J Indian Soc Pedod Prev Dent"},{"issue":"3","key":"7934_CR24","doi-asserted-by":"publisher","first-page":"96","DOI":"10.25121\/NewMed.2019.23.3.96","volume":"23","author":"A Kobyli\u0144ska","year":"2019","unstructured":"Kobyli\u0144ska A, Piekoszewska-Zi\u0119tek P, Gozdowski D, Turska-Szybka A, Olczak-Kowalczyk D. Spatial changes in the dental arch after premature extraction of the first primary molar \u2013 a 12-month observational study. New Med. 2019;23(3):96\u2013104.","journal-title":"New Med"},{"issue":"6","key":"7934_CR25","doi-asserted-by":"publisher","first-page":"383","DOI":"10.1111\/j.1365-263X.2009.00990.x","volume":"19","author":"K Park","year":"2009","unstructured":"Park K, Jung DW, Kim JY. Three-dimensional space changes after premature loss of a maxillary primary first molar. Int J Paediatr Dent. 2009;19(6):383\u20139.","journal-title":"Int J Paediatr Dent"},{"issue":"8","key":"7934_CR26","doi-asserted-by":"publisher","first-page":"e1012","DOI":"10.4317\/jced.61891","volume":"16","author":"S Kanokpoonsin","year":"2024","unstructured":"Kanokpoonsin S, Peanchitlertkajorn S, Saengfai NN, Boonpratham S. A comparison of tooth size and arch dimensions among measurements taken intraorally with 3D-printed and digital models obtained from intraoral scans. J Clin Exp Dent. 2024;16(8):e1012\u201320.","journal-title":"J Clin Exp Dent"},{"issue":"10","key":"7934_CR27","doi-asserted-by":"publisher","first-page":"1577","DOI":"10.1177\/00220345800590100401","volume":"59","author":"WM Northway","year":"1980","unstructured":"Northway WM, Wainright RW. D E space\u2013a realistic measure of changes in arch morphology: space loss due to unattended caries. J Dent Res. 1980;59(10):1577\u201380.","journal-title":"J Dent Res"},{"key":"7934_CR28","doi-asserted-by":"publisher","first-page":"7604144","DOI":"10.1155\/2022\/7604144","volume":"2022","author":"A Heidari","year":"2022","unstructured":"Heidari A, Mokhtari S, Hamrah MH, Tavana Z, Heydarigoojani M, Tavana N. Investigating the factors affecting the need for unilateral space maintainer for first primary molars in late mixed dentition. Biomed Res Int. 2022;2022:7604144.","journal-title":"Biomed Res Int"},{"issue":"3","key":"7934_CR29","doi-asserted-by":"publisher","first-page":"188","DOI":"10.1016\/S1073-8746(95)80022-0","volume":"1","author":"AA Gianelly","year":"1995","unstructured":"Gianelly AA. Leeway space and the resolution of crowding in the mixed dentition. Semin Orthod. 1995;1(3):188\u201394.","journal-title":"Semin Orthod"},{"issue":"1","key":"7934_CR30","doi-asserted-by":"publisher","first-page":"16","DOI":"10.1053\/j.sodo.2013.12.003","volume":"20","author":"RA Bell","year":"2014","unstructured":"Bell RA, Sonis A. Space supervision and guidance of eruption in management of lower transitional crowding: a non-extraction approach. Semin Orthod. 2014;20(1):16\u201335.","journal-title":"Semin Orthod"},{"issue":"2","key":"7934_CR31","first-page":"127","volume":"19","author":"I Kocadereli","year":"1995","unstructured":"Kocadereli I, Ciger S. Retention of orthodontic bands with three different cements. J Clin Pediatr Dent. 1995;19(2):127\u201330.","journal-title":"J Clin Pediatr Dent"},{"key":"7934_CR32","unstructured":"Cobourne MT, DiBiase AT. Handbook of orthodontics. Elsevier Health Sciences; 2015."},{"issue":"6","key":"7934_CR33","doi-asserted-by":"publisher","first-page":"1045","DOI":"10.2319\/030711-165.1","volume":"81","author":"A Sonis","year":"2011","unstructured":"Sonis A, Ackerman M. E-space preservation. Angle Orthod. 2011;81(6):1045\u20139.","journal-title":"Angle Orthod"},{"issue":"1","key":"7934_CR34","doi-asserted-by":"publisher","first-page":"395","DOI":"10.1186\/s12903-021-01755-1","volume":"21","author":"S Arunachalam","year":"2021","unstructured":"Arunachalam S, Sivakumar I, Jayaraman J, Sharan J. Does arch length preservation in mixed dentition children affect mandibular second permanent molar eruption? A systematic review and meta-analysis. BMC Oral Health. 2021;21(1):395.","journal-title":"BMC Oral Health"},{"issue":"6","key":"7934_CR35","doi-asserted-by":"publisher","first-page":"721","DOI":"10.1093\/ejo\/19.6.721","volume":"19","author":"KK Yuen","year":"1997","unstructured":"Yuen KK, So LL, Tang EL. Mesiodistal crown diameters of the primary and permanent teeth in southern Chinese\u2013a longitudinal study. Eur J Orthod. 1997;19(6):721\u201331.","journal-title":"Eur J Orthod"},{"issue":"4","key":"7934_CR36","doi-asserted-by":"publisher","first-page":"493","DOI":"10.1002\/ajpa.1330480408","volume":"48","author":"B Margetts","year":"1978","unstructured":"Margetts B, Brown T. Crown diameters of the deciduous teeth in Australian Aboriginals. Am J Phys Anthropol. 1978;48(4):493\u2013502.","journal-title":"Am J Phys Anthropol"},{"issue":"2","key":"7934_CR37","doi-asserted-by":"publisher","first-page":"113","DOI":"10.1093\/ejo\/4.2.113","volume":"4","author":"L Lysell","year":"1982","unstructured":"Lysell L, Myrberg N. Mesiodistal tooth size in the deciduous and permanent dentitions. Eur J Orthod. 1982;4(2):113\u201322.","journal-title":"Eur J Orthod"},{"issue":"3","key":"7934_CR38","doi-asserted-by":"publisher","first-page":"181","DOI":"10.3109\/00016358309162321","volume":"41","author":"G Axelsson","year":"1983","unstructured":"Axelsson G, Kirveskari P. Crown size of permanent teeth in Icelanders. Acta Odontol Scand. 1983;41(3):181\u20136.","journal-title":"Acta Odontol Scand"},{"issue":"6","key":"7934_CR39","doi-asserted-by":"publisher","first-page":"339","DOI":"10.3109\/00016358409033613","volume":"42","author":"G Axelsson","year":"1984","unstructured":"Axelsson G, Kirveskari P. Crown size of deciduous teeth in Icelanders. Acta Odontol Scand. 1984;42(6):339\u201343.","journal-title":"Acta Odontol Scand"},{"key":"7934_CR40","unstructured":"Moyers RE, van der Linden FPGM, Riolo ML, McNamara JA, Wainright RL, Guire KE, Miller RL. Standards of human occlusal development. Center for Human Growth and Development, University of Michigan; 1976."},{"key":"7934_CR41","doi-asserted-by":"publisher","unstructured":"de Souza BB, Evangelista ME, Andriani JS, Cardoso M, Santana CM, Bolan M. Assessment of space changes in the lower dental arch after the premature loss of a primary molar: a randomized clinical trial. Int J Paediatr Dent. 2024;34(6):906\u201314. https:\/\/doi.org\/10.1111\/ipd.13239.","DOI":"10.1111\/ipd.13239"}],"container-title":["BMC Oral Health"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/article\/10.1186\/s12903-026-07934-2","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s12903-026-07934-2.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s12903-026-07934-2.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T19:55:41Z","timestamp":1781639741000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1186\/s12903-026-07934-2"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,13]]},"references-count":41,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,12]]}},"alternative-id":["7934"],"URL":"https:\/\/doi.org\/10.1186\/s12903-026-07934-2","relation":{},"ISSN":["1472-6831"],"issn-type":[{"value":"1472-6831","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,3,13]]},"assertion":[{"value":"5 February 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"12 February 2026","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"13 March 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"Not applicable.","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":"611"}}