In adults, the bone may be broken at the symphysis as a result of lateral compression of the jaw-for example, pressing together of the angles.
"Manual of Surgery Volume Second: Extremities--Head--Neck. Sixth Edition."
Alexander Miles Alexis Thomson
The inner surface of the jaw at the point of the suture or symphysis, forms a line obliquely directed upwards.
"A Manual of the Antiquity of Man"
J. P. MacLean
The bones of the lower jaw are not united at the symphysis, but are held together by strong fibrous bands; the two rami are very much rounded and arched outwards; there are no teeth.
"Natural History of the Mammalia of India and Ceylon"
Robert A. Sterndale