The relative accuracy of dynamic navigation-guided and conventional coronectomy for mandibular third molars: A randomized controlled trial

Bin-Zhang Wu; Jia-Nan Lin; Qian-Xiao Liu; Peng-Fei Jia; Ao-Bo Jin; Liang-Wei Chen; Zi-Yu Yan; Nian-Hui Cui

doi:10.1016/j.jdent.2026.106621

The relative accuracy of dynamic navigation-guided and conventional coronectomy for mandibular third molars: A randomized controlled trial

J Dent. 2026 Jun:169:106621. doi: 10.1016/j.jdent.2026.106621. Epub 2026 Mar 10.

Authors

Bin-Zhang Wu¹, Jia-Nan Lin², Qian-Xiao Liu³, Peng-Fei Jia⁴, Ao-Bo Jin⁵, Liang-Wei Chen⁶, Zi-Yu Yan⁷, Nian-Hui Cui⁸

Affiliations

¹ First Clinical Division, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, PR China. Electronic address: wubinzhang@bjmu.edu.cn.
² Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, PR China. Electronic address: MedCanaan@163.com.
³ Beijing Stomatological Hospital, School of Stomatology, Capital Medical University, Beijing, PR China. Electronic address: lqx2022@mail.ccmu.edu.cn.
⁴ Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, PR China. Electronic address: jiapengfei123123@126.com.
⁵ Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, PR China. Electronic address: aobojin01@163.com.
⁶ Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, PR China. Electronic address: chenliangwei@bjmu.edu.cn.
⁷ Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, PR China. Electronic address: yanziyu@bjmu.edu.cn.
⁸ Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology & National Center for Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Research Center of Oral Biomaterials and Digital Medical Devices, Beijing, PR China. Electronic address: drcuinianhui@163.com.

PMID: 41812978
DOI: 10.1016/j.jdent.2026.106621

Abstract

Objectives: This study aimed to evaluate and compare the surgical precision of coronectomy for mandibular third molars (M3Ms) performed with the aid of a dynamic navigation system (DNS) versus the conventional freehand technique.

Methods: A single-blind randomized controlled trial was conducted in 110 patients undergoing M3M coronectomy. After withdrawal of three patients, 107 patients (teeth, N = 117) were included in the final analysis. Teeth were randomly allocated to the DNS-assisted group (patients, n = 52; teeth, N = 57) or the freehand group (patients, n = 55; teeth, N = 60). The primary outcome measure was the root mean square (RMS) deviation between the achieved osteotomy plane and the preoperative virtual plan, assessed for the entire resection surface as well as the mesial and distal subregions. Secondary outcomes included: (i) maximum and mean positive and negative deviations in all regions; (ii) curvature parameters (RMS, maximum, and minimum) for the complete osteotomy plane and its subregions; and (iii) total procedure duration and active operative time. Postoperative cone-beam computed tomography (CBCT) scans were processed with Geomagic software for three-dimensional deviation analysis.

Results: The DNS-assisted group showed significantly reduced RMS deviations (overall: 1.02 ± 0.50 mm; mesial: 1.06 ± 0.58 mm; distal: 0.92 ± 0.54 mm) compared with the freehand group (overall: 1.44 ± 0.90 mm; mesial: 1.46 ± 1.07 mm; distal: 1.48 ± 1.25 mm; P < 0.05). Consistent advantages of DNS were also observed in maximum and mean positive deviations, RMS curvature, and minimum curvature values. However, operative duration was significantly longer with DNS than with the freehand method (28 min vs. 14 min, P < 0.05).

Conclusions: Dynamic navigation significantly improves the accuracy of M3M coronectomy, achieving millimeter-level precision that surpasses that of the freehand technique.

Clinical significance: These findings highlight the value of a fully digital workflow from preoperative planning through postoperative validation in DNS-guided coronectomy, underscoring its potential to improve safety and precision in complex M3M surgeries.

Keywords: Accuracy; Computer-assisted surgery; Coronectomy; Dynamic navigation system; Mandibular third molar; Oral and maxillofacial surgery.

Publication types

Randomized Controlled Trial
Comparative Study

MeSH terms

Adult
Cone-Beam Computed Tomography / methods
Female
Humans
Male
Mandible* / diagnostic imaging
Mandible* / surgery
Middle Aged
Molar, Third* / diagnostic imaging
Molar, Third* / surgery
Operative Time
Osteotomy / methods
Single-Blind Method
Surgery, Computer-Assisted* / methods
Tooth Crown* / diagnostic imaging
Tooth Crown* / surgery
Tooth Extraction / methods
Tooth, Impacted / surgery
Treatment Outcome
Young Adult