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©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
Separated root tip formation associated with a fractured tubercle of dens evaginatus: A case report
Zhi-Fang Wu, Ling-Jiao Lu, Hai-Yan Zheng, Yan Tu, Ying Shi, Zi-Huai Zhou, Lin-Xian Fang, Bai-Ping Fu
Zhi-Fang Wu, Lin-Xian Fang, Department of Pediatric Dentistry, The Affiliated Hospital of Stomatology, School of Stomatology, Zhejiang University School of Medicine, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou 310006, Zhejiang Province, China
Ling-Jiao Lu, Hai-Yan Zheng, Ying Shi, Zi-Huai Zhou, Bai-Ping Fu, Department of Prosthodontics, The Affiliated Hospital of Stomatology, School of Stomatology, Zhejiang University School of Medicine, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou 310006, Zhejiang Province, China
Yan Tu, Department of Endodontics, The Affiliated Hospital of Stomatology, School of Stomatology, Zhejiang University School of Medicine, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Hangzhou 310006, Zhejiang Province, China
Author contributions: Wu ZF and Tu Y were the patient’s dentists, reviewed the literature and contributed to manuscript drafting; Lu LJ, Zheng HY and Zhou ZH reviewed the literature and contributed to manuscript drafting; Shi Y and Fang LX analyzed and interpreted the imaging findings; Fu BP were responsible for the revision of the manuscript for important intellectual content; All authors issued final approval for the version to be submitted.
Supported by National Natural Science Foundation of China, No. 81801028; and Natural Science Foundation of Zhejiang Province, No. LQ19H140001.
Informed consent statement: Informed written consent was obtained from the patient for publication of this report and any accompanying images.
Conflict-of-interest statement: The authors declare that they have no conflict of interest.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Bai-Ping Fu, PhD, Director, Professor, Department of Prosthodontics, The Affiliated Hospital of Stomatology, School of Stomatology, Zhejiang University School of Medicine, Key Laboratory of Oral Biomedical Research of Zhejiang Province, No. 395 Yan’an Road, Hangzhou 310006, Zhejiang Province, China. fbp@zju.edu.cn
Received: January 7, 2021
Peer-review started: January 7, 2021
First decision: January 24, 2021
Revised: January 25, 2021
Accepted: February 24, 2021
Article in press: February 24, 2021
Published online: April 26, 2021
BACKGROUND
Several previous studies have reported an unusual root formation in which a fractured apical fragment of an immature root continued to develop independent of the main root after trauma to an immature tooth. To date, there have been only rare reports of the continuing apical formation of the fractured root associated with dens evaginatus (DE). This paper presents a case of a separated root tip formation associated with a fractured tubercle of DE.
CASE SUMMARY
An 11-year-old boy was referred for gingival sinus on the buccal side of the right mandibular second premolar (tooth # 45). Clinically, tooth # 45 was free of caries, but there was a sign of a fractured tubercle of DE on the occlusal surface. Radiography showed that the root canal of tooth # 45 was widely radiolucent. A separated root apex was found apically under the main root and was nearly completely formed with an apical orifice at the apical tip. Tooth # 45 was diagnosed as tubular fracture of DE with chronic apical periodontitis. A revascularization technique was recommended to treat the tooth. At 3-mo and 1-yr follow-up, the patient remained asymptomatic. Periapical radiography revealed that the separated root tip distally drifted with closure of the apex. However, the root length and thickness of the main root did not increased.
CONCLUSION
Clinicians should be aware that even if tubercle of DE is fractured in an immature tooth, the root tip may be separated from the main root and completely formed.
Core Tip: Studies have reported an unusual root formation where a fractured apical fragment of an immature root continued to develop independent of the main root after trauma to an immature tooth. There are only rare reports of continuing apical formation of the fractured root associated with dens evaginatus. We present a case of a separated root tip formation associated with a fractured tubercle of dens evaginatus. The case highlights that clinicians should be aware that even if the tubercle of dens evaginatus is fractured in an immature tooth, the root tip may be separated from the main root and completely formed.
