This section of the book is from "The Complete Herbalist" by Dr. O. Phelps Brown. Also available from Amazon: The Complete Herbalist: The People Their Own Physicians By The Use Of Nature's Remedies.
This is often caused by yawning, by convulsions, or by blows on the chin, when the mouth is wide open. The mouth gapes and cannot be shut, the saliva trickles, there is great pain, and the patient cannot talk.
TREATMENT. -- Seat the patient on a low stool, stand in front of him, and then press your thumbs upon the last molar or grinding teeth very firmly. Be careful, however, to have your thumbs well protected with wrappings, or else you may be severely bitten. By doing this you get the articular ends of the jaw-bone from their unnatural position, and reduction is caused by the normal action of the muscles. When you hear the snap, you may be sure that the bone is in its proper position. After reduction, the chin should be confined by a bandage for a week or ten days.