Physical neurosensory testing versus current perception threshold assessment in trigeminal nerve injuries related to dental treatment: a retrospective study.
OBJECTIVE
To provide a preliminary comparison of traditional clinical neurosensory examination (CNE) and current perception threshold (CPT).


METHODS
This is a retrospective chart audit of patients with trigeminal nerve injuries related to dental treatment who were evaluated with both CNE and CPT assessments (electrical stimulus tests) after presenting with altered sensation involving either the inferior alveolar nerve (IAN) or lingual nerve (LN) distributions. The tests were performed on the anterior two-thirds of the tongue for LN injuries and the lower lip and chin for IAN injuries. Results were defined as hyper-, hypo-, or normal sensory response.


RESULTS
Twelve charts were reviewed; 10 of the 12 nerve injuries occurred secondary to mandibular third molar extraction affecting 7 LN and 5 IAN branches. Following LN injuries, the C, and A-delta fibers assessment demonstrated hyposensitivity in the affected nerve territory in CPT and the CNE tests with the exception of 1 normal nerve response in 5-Hz CPT. Within the LN injury group, good correlation was observed between the CNE and CPT tests with the exception of brush stroke and 250-Hz CPT stimuli. Following IAN injuries, sensory testing results were more varied. A-beta fiber evaluation demonstrated hyposensitivity to VF in all patients and in 4 of 5 for brush test. One patient was hypersensitive for the brush test. The response to 2,000-Hz electrical stimulus demonstrated hyposensitivity in 3 patients, hypersensitivity in 1 (the same patient that was hypersensitive for brush), and normal sensitivity in 1 patient. Good correlations were found only between the CPT 5-Hz and heat and cold tests. Only 1 patient (IAN injury) reported pain that was hypersensitive for heat, cold, pinprick, brush, and 250-Hz and 2,000-Hz stimuli.


CONCLUSIONS
Following LN injuries, CNE and CPT tests provided similar findings. More disparity was observed between the CNE and CPT methods in the IAN injury evaluation. For LN injury assessments, CNE alone appears to be adequate for assessing nerve injuries.
Ziccardi
Vincent B
VB
Department of Oral and Maxillofacial Surgery, UMDNJ, Newark, New Jersey 07101, USA. ziccarvb@umdnj.edu
Hullett
Jason S
JS
Gomes
Julyana
J
D000328:Adult; D020209:Cranial Nerve Injuries / Q000175:diagnosis*; D004558:Electric Stimulation; D005260:Female; D006801:Humans; D061222:Lingual Nerve Injuries; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000502:physiology; D009460:Neurologic Examination / Q000379:methods*; D017288:Pain Threshold; D012189:Retrospective Studies; D012684:Sensory Thresholds; D014081:Tooth Extraction / Q000009:adverse effects; D061221:Trigeminal Nerve Injuries; D055815:Young Adult