Accuracy of Diagnostic Methods for Peripheral Trigeminal Nerve Injuries: A Systematic Review

Post-traumatic trigeminal neuropathy following oral and maxillofacial procedures may cause persistent neurosensory disturbances and neuropathic pain, yet the diagnostic performance of the available assessment methods remains uncertain.

This systematic review evaluated the accuracy of diagnostic methods used to detect peripheral trigeminal nerve injuries in the maxillary and mandibular regions after oral and maxillofacial procedures.

PubMed, Scopus, and Cochrane databases were searched in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Diagnostic accuracy and observational studies evaluating clinical, neurophysiological, or imaging-based methods for peripheral trigeminal nerve injuries were included, while non-English and nonhuman studies, reports lacking relevant diagnostic performance data, studies outside the maxillary or mandibular regions, and nonoriginal research were excluded. Risk of bias was assessed using Quality Assessment of Diagnostic Accuracy Studies 2.

The search identified 2914 records, of which 10 studies (0.3%) were included in the final synthesis, comprising n = 520 participants and k = 514 injured or evaluated nerves. The included studies comprised 5 prospective diagnostic accuracy studies, 2 retrospective diagnostic accuracy studies, 2 case-control diagnostic accuracy studies, and one cross-sectional observational study. Clinical neurosensory testing showed 96% accuracy, 100% sensitivity, 62.5% specificity, 95% positive predictive value (PPV), and 100% negative predictive value (NPV) for lingual nerve (LN) injuries, compared with 73% accuracy, 85% sensitivity, 47% specificity, 77% PPV, and 60% NPV for inferior alveolar nerve injuries. The tongue somatosensory evoked magnetic field laterality index showed 95.7% accuracy, 92.3% sensitivity, 100% specificity, 100% PPV, and 90.9% NPV for LN injury.

Clinical neurosensory testing was widely used but had variable diagnostic performance, with lower values for inferior alveolar nerve injuries. Quantitative sensory testing and neurophysiological methods provided more balanced diagnostic profiles, especially when combined. Magnetic resonance neurography demonstrated high specificity but variable sensitivity, with greater clinical value for high-fgrade injuries. The highest single-test accuracy was reported for tongue somatosensory evoked magnetic fields in LN injury. Overall, these findings support a multimodal diagnostic approach when objective confirmation, injury grading, anatomical localization, or treatment planning is required.