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Case Reports
. 2025 Jan 2;25(1):8.
doi: 10.1186/s12903-024-05329-9.

Removal of a fractured file beyond the apical foramen using robot-assisted endodontic microsurgery: a clinical report

Mei Fu #  1 , Shen Zhao #  1 , Xubing Zhou  1 , Benxiang Hou  2 , Chen Zhang  3
Affiliations
Case Reports

Removal of a fractured file beyond the apical foramen using robot-assisted endodontic microsurgery: a clinical report

Mei Fu et al. BMC Oral Health. .

Abstract

Background: Endodontic file fractures are common complications of root canal treatment, and requires removal via specialized techniques such as endodontic microsurgery when the file beyond the apical foramen. It is often challenging to precisely and minimally remove a fractured file. Recently the use of dental autonomous robotic system (ATR) has shown promise in precisely and minimally in dental surgery. Therefore, this case details a technique for using the ATR system to precisely and minimally guide the removal of a fractured file beyond the apical foramen.

Case presentation: A 48-year-old male patient, with no evidence of bone defects, was diagnosed with a file fractured completely beyond the apical foramen during root canal treatment of the right maxillary lateral incisor. Patient information was used to incorporate a digital model into preoperative planning software to develop a surgical strategy. The ATR system employs spatial alignment methods for registration, directing the robotic arm to independently locate the fractured file in accordance with the surgical plan. To maximize minimally invasive surgery, the long fractured file was removed in two stages. After removing the bone and fracture file, the clinician performed suturing under a microscope. No complications were observed during the surgery, and the treatment appeared to be successful based on the 9-month follow-up evaluation.

Conclusions: The ATR system enables precise localization of the fractured file beyond the apical foramen with intact cortical plates. This technology has the potential to improve positioning accuracy, minimize the need for invasive bone removal, reduce intraoperative time, and facilitate successful endodontic microsurgical procedures.

Keywords: Apical microsurgery; Autonomous; Fractured file removal; Osteotomy; Robotic system.

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Conflict of interest statement

Declarations. Ethics approval and consent to participate: This study did not involve human or animal subjects’ experiment, and thus no ethical approval was required. The case report adhered to the guidelines established by the journal. Consent for publication: Patient gave their written informed consent for their personal or clinical details along with any identifying images to be published in this case report. Competing interests: The authors declare no competing interests.

Figures

Fig. 1
Fig. 1
Preoperative examination (A) Intraoral radiograph (B)(C) intraoral photograph (D)(E)(F) CBCT view
Fig. 2
Fig. 2
Surgical planning (A) (B) Illustrate the surgical approach using both cone beam computed tomography (CBCT) and oral scan models. (C) (D)(E) Illustrate the surgical approach on CBCT. Green circle: Drill entry position. Green square: Drill entry deoth and direction
Fig. 3
Fig. 3
Surgical procedure (A) Preperactive intraoral radiograph (B) (C) Registration (D) Osteotomy procedure. Notice that the hole process is automatically completed by the robot arm. (E) Bone window prepared by ATR system (F) Taking out the fracture through the keyhole shape bone window (G) Fractured file (H) radiographic images immediately after surgery
Fig. 4
Fig. 4
Postoperative examination results (A) 3-months follow-up radiographic images (B) 9-months follow-up radiographic images (C) (D) 9-months follow-up intraoral photograph
See this image and copyright information in PMC

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