In the context of surgery or dental surgery, Jennings Gag is a device used to hold the patient’s mouth open when working in the oral cavity, or to force the mouth open when it cannot open naturally because of forward dislocation of the jaw joint’s intraarticular cartilage pad.
These type of gags are also used in sexual fetish or bondage play. Such gags allow unlimited access to the mouth. They stop coherent speech, but do little to silence a person.

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