Management of accidental tooth root displacement into the mandibular canal during tooth extraction

doi:10.7518/hxkq.2025.2025298

Abstract

Abstract:

The accidental displacement of tooth roots into the mandibular canal is a serious complication during tooth extractions in oral and maxillofacial surgery, often resulting in direct damage to the structural and functional integrity of the inferior alveolar neurovascular bundle (IANB). This article reviews the anatomical features of the mandibular canal, the IANB, and adjacent tooth roots; identifies high-risk factors and anatomically vulnerable sites for root displacement; and outlines the clinical manifestations and radiographic characteristics of intraoperative root intrusion into the mandibular canal. Furthermore, management principles, surgical approaches and techniques, inferior alveolar nerve injury treatment, and prognostic considerations are discussed. The aim of this review is to provide a comprehensive clinical reference for improving surgical outcomes, and reducing postoperative complications.

Key words: mandibular canal, root displacement, inferior alveolar nerve, complication, surgery

CLC Number:

R782.1

Su Liwen, Zhao Jihong. Management of accidental tooth root displacement into the mandibular canal during tooth extraction[J]. West China Journal of Stomatology, 2025, 43(6): 789-796.

Figures/Tables 6

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References 29

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分级	痛觉与触觉	两点辨别觉/mm	电生理特征
S0	支配区感觉完全丧失	无法检测	无动作电位
S1	深部痛觉存在	-	潜伏期延长>6 ms
S2	表浅痛觉/触觉部分恢复	>15	传导速度<30 m/s
S2+	感觉过敏伴痛觉异常	>15	异常自发电位
S3	触觉恢复伴定位障碍	7~15	传导速度30~40 m/s
S3+	精细触觉部分恢复	≤6	传导速度40~50 m/s
S4	感觉完全正常	≤3	传导速度＞50 m/s