Risk of Postsurgical Inferior Alveolar Nerve Injury in At-Risk Patients Based on Tomographic Imaging Features:...

Area of Science:

• Oral and Maxillofacial Surgery
• Radiology
• Neurosurgery

Background:

• Inferior alveolar nerve (IAN) injury risk after mandibular third molar surgery is poorly defined due to lack of tomographic stratification.
• Individualized risk assessment and surgical planning are limited without considering specific tomographic risk factors.

Purpose of the Study:

• To estimate the risk of IAN injury in at-risk patients based on cone-beam computed tomography (CBCT) features.
• To analyze the association between mandibular canal (MC) characteristics (position, shape, cortical status) and third molar morphology with IAN injury risk.

Main Methods:

• Systematic review and meta-analysis adhering to PRISMA guidelines, searching multiple databases (MEDLINE, EMBASE, Web of Science, Scopus, Cochrane, Google Scholar).
• Inclusion of prospective and retrospective cohort studies with preoperative CBCT and objective neurosensory testing for IAN injury.
• Exclusion of studies with subjective assessments, lacking CBCT data, or unrelated outcomes; risk of bias assessed using Joanna Briggs Institute tool.

Main Results:

• Eleven studies (1.05%) met inclusion criteria. Pooled overall IAN injury risk was 9.52%, rising to 14.76% in high-risk cases.
• Stratified analysis revealed significant risk variations: 1.34-27.47% (MC position), 6.56-18.36% (MC shape), 15.65% (no MC cortical bone), and 0.39% (cortical bone present).

Conclusions:

• CBCT-based tomographic features are strongly associated with varying risks of IAN injury.
• Risk-stratified preoperative assessment using CBCT is crucial for surgical planning and patient counseling in third molar surgery.
• Low to very low certainty of evidence highlights the need for high-quality studies to improve IAN injury risk prediction.