Musannaf Ibn Abi Shaybah 28665 — The chin and the jawbones: what

Ibn Jurayj said: It was related to me from Sa'id bin al-Musayyib that he said, regarding the two jaws of a person, that the blood money for broken jaws will be estimated with the thumb, in this way: his thumb is bent, then its lower segment is placed, and he opens his mouth and places them between his two jawbones; then whatever the opening of his mouth falls short of the lower segment of his thumb, the blood money will be in proportion to it.