Method for preventing degradation of a fluid dielectric in an RF device. Each actuator includes a lever pivotable about a fulcrum axis. The control unit automatically changes the safety margin in accordance with a predetermined relationship between the safety margin and the measured threshold value, so that the safety margin is progressively increased as the measured threshold value increases. The user interface identifies each annotation by a short subject line. The implant has a covering layer that is preferably made of aluminium oxide and provided with uniform cavities and separate openings on the surface side of the covering layer in order to receive a therapeutic agent which can be released according to requirements when the implant is in place.