An electrosurgical instrument having opposing end effectors and a handle for effecting movement of the end effectors relative to one another, includes a pair of electrodes each including an electrically conductive surface (e.g., which can be dimensioned for sealing, clamping and/or cutting), an insulating substrate having a first edge, and an insulating layer positioned in a channel formed by the electrically conductive surface within the first edge between the conductive surface and the first edge of the insulating substrate. The insulating layer has a portion proximal to the electrically conductive surface and a portion distal from the electrically conductive surface and a gradient such that the proximal portion has a lower dielectric strength than the distal portion. A coating on one of the pair of electrodes may be disposed in at least partial non-vertical registration with a coating on the opposing one of the pair of electrodes.