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Separate apical root formation of injured immature teeth: a case series and literature review

  • Minjung Kim1
  • Yujeong Kim1
  • Minju Song1,*,

1Department of Conservative Dentistry, College of Dentistry, Dankook University, 31116 Cheonan, Republic of Korea

DOI: 10.22514/jocpd.2023.095

Submitted: 15 May 2023 Accepted: 06 July 2023

Online publish date: 16 November 2023

*Corresponding Author(s): Minju Song E-mail:


This report presents three cases of separated root tip formation following traumatic injury with or without inflammation. The first case showed continued separate apical root formation; however, development of the main root with bony ingrowth was absent. The second case showed that separated root formation continued under the 2-year inflammatory conditions, even after apexification. The third patient showed partially connected root tip formation after apexification. By summarizing previously reported similar cases, we assessed the injury type, prevalence age, treatment performed and pattern of root development. This phenomenon may be elucidated by the special features of the apical papilla (AP). Understanding the capability of AP could help with treatments, such as regenerative endodontic procedures and trauma management for immature permanent teeth.


Apical papilla; Hertwig’s epithelial root sheath (HERS); Separated root tip; Trauma; Inflammation

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Minjung Kim,Yujeong Kim,Minju Song. Separate apical root formation of injured immature teeth: a case series and literature review. Journal of Clinical Pediatric Dentistry. 2024.doi:10.22514/jocpd.2023.095.


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