Mandibula
latin: Os mandibula
common: (lower) Jaw bone
The jaw bone (mandibula) is the largest bone in the human face. It is the only bone in the skull that can be moved in respect to the other skull bones (the lingual bone and the six middle ear bones are not regarded a part of the skull).
Function of the jaw bone
The most important function of the jaw bone is to chew. The jaw bone keeps the teeth in place and is designed (or evaluated) to make chewing movements.
The shape of the two jaw joints allow you to move the jaw up and down, left and right and front- and backward. The corners of the jaw bone meet the temporal bone to create the joint. The jaw points can slide over the temporal bone and make a rotating movement.
Impact on the facial appearance
The shape of the jaw bone has a large influence on what the face looks like. Women usually have a more pointed jaw bone and man a broad square one, which makes the chin look pointed or broad. Also whether the jaw bone is small (placed backward) or large (placed forward) makes a difference in appearance.
By the way, the differences in shape of the jaw bones of woman among themselves and man among themselves is large and there is quite some overlap between man and woman. Therefore it is not possible on the shape of the jaw bone alone to determine whether it is a male or female bone.
Jaw Surgery
large jaw bone
small jaw bone
Sometimes the shape of the jaw bone doesn't look nice or causes the teeth not to fit on each other. In some cases it is therefor decided to go for jaw surgery (orthognathic surgery). In order to improve the jaw position or shape, cuts are made in the jaw bone and the pieces are then realigned as necessary, and fixed in place.
These operations usually have a large impact and it takes a long time before the pieces are grown together. It might be impossible to eat solid food for about 6 weeks. The good things of these operations is that no scars are left on the outside, as everything is done from the inside of the mouth.