Exactly what it says on the tin: how can a repressive government quickly but non-permanently disable human vocal cords in a way that allows only that government to restore them?
Said government uses vocal cord disabling, among other things, as a terror tactic: speak out, and they'll literally remove your free speech. How would this work? For instance:
Is there some kind of substance that can be applied to vocal cords in order to stop them from functioning?
Do vocal cords not work if some kind of protein is missing?
Can some kind of substance be injected into the neck to paralyze the larynx?
Can an anesthetic be injected followed by the vocal cords being manually severed?.
Can something be inserted into the trachea to wedge the vocal cords open while still enabling breathing?
Preferably, whatever this is can be done with in minutes, is fully reversible, is only fully reversible by the government, poses no ill effects to the victim's health beyond removing their ability to speak, and is painless, but I'm willing to accept answers that don't meet those criteria if any of them are impossible or improbable. I'm also willing to go as far as defining "transplanting a larynx to fit the old one" in terms of "reversible".
Presume that the setting's tech level/tech availability is capable of doing things like transplanting larynxes on a widespread scape - I know it's been done in real life on occasion, but IIRC, it's only been twice.
Also, I don't want answers related to cutting tongues out; the authoritarian, repressive government would rather that their victims remain unblemished in that regard.