The most common form of fracture of this bone is that in which it becomes broken away from its fellow at their joining, and displaced either to one side or in an upward or downward direction. Fracture through the body or the nasal process may occur, but these forms are comparatively rare.

Kicks, blows, and falls on the mouth are accountable for many cases of this mishap, and in several instances the writer has seen the bone torn from its fellow in the struggles to remove the incisor teeth from some confined position, such as when fixed in an iron ring or between a hook and the wall of the stable.

Symptoms

Some distortion of the face on the side of the fracture, in which the upper lip is either raised or depressed or drawn to one side, is usually present when displacement takes place. There is some discharge of saliva from the mouth for a while, and frequent movement of the lips.

When the body is broken across, the fragment containing the incisor teeth is movable and emits a crepitus. When the body of one bone is broken away from the other the displaced portion may be firmly fixed in an upward, downward, or outward direction. If, as sometimes occurs, it is also broken across, then it will be freely movable.

Treatment

The simplest form of fracture, and the one most amenable to treatment, is that in which one bone is torn away from the other. In this case replacement may be effected by means of a little pressure and manoeuvring with the hand, or it may require the use of a pair of large pincers, as already prescribed for the lower jaw, to bring the displaced part into position.

Broken teeth must be removed, and any that may be found to be pushed out of place should be properly restored to their natural position.

Any bits of bone that may be loose and detached must be taken away. If allowed to remain, their presence will excite irritation and pus formation in the surrounding tissues and retard reparation.

The broken fragments may be retained in position by copper wire bound round the incisor teeth.

During the first forty-eight hours the patient should be kept exclusively on thick gruel, and afterwards on sloppy bran diet, other forms of aliment being gradually added as the case progresses.

It is desirable to keep the horse in pillar reins for a short time after the parts have been readjusted.