The study of trigeminal somatosensory evoked potentials by electric stimulating of maxillary nerve

Objective In order to explore the feature of trigeminal somatosensory evoked potential(TSEP) of the branch of maxillary nerve,and compare it with other branches of trigeminal nerve.Methods The TSEPs were recorded in ten health adults by electric stimulating of the infraorbital nerve-one branch of maxillary nerve of both sides,Results ①The first positive peak(P1) appeared at 20ms after stimulation,then the other nine peaks from N1 to N5 in succession.②In these peaks,the latencies of P3,N3 and P4 were stable,the amplitude of N3～N4 developed perendicular decline and great extent,the wave figures showed regular.③There were no significant difference on TSEPs between maxillary nerve and mandibular nerve.Conclusion The highest potential of the TSEPs of maxillary nerve appeared at N3P4 which occurred at 110ms.The amplitude was above 10μV,and the latency was stable relatively.The above-mentioned formed the characteristic of the TSEPs of maxillary nerve.In the early stage the amplitudes of P1 to N2 were low,but there would be a great variation by the changes of the teminal branches of maxillary nerve.The latencies,amplitudes,spike potential and figures of the TSEPs of maxillary nerve and mandibular nerve were similar.All of these parameters could be used to evaluate the functional condition and diagnoses of the disorders of maxillary nerve in the future.