This study evaluated the effect of the fifth-generation dentin adhesives, Single Bond (SB), Excite (EX), Prime & Bond NT (PB), and Optibond Solo (OS) on nerve conduction. Isolated rat sciatic nerves were placed between two suction electrodes in a bath containing tyrode solution. The bonding agents were brought into contact with the nerves and the evoked compound action potentials (cAPs) were recorded before and after contact with the materials. SB, EX, and PB caused total inhibition of the cAPs, with PB being the fastest (73 +/- 5.8 min). All cAPs except one in the PB group were irreversibly inhibited in the SB, EX, and PB groups. As for OS the reduction in cAP was not 50% after an application time of 200 min. Recovery of the cAPs in this group was recorded in an average time of 35 min.