As the facial artery ascends superiorly toward the corner of the mouth, lateral border of the nose, and inner corner of the eye, it follows a winding course that permits unimpeded blood flow as the lips and cheeks expand and move.

Near the corner of the eye, the facial artery terminates as the angular artery (14), anastamosing with branches of the opthalmic and frontal arteries.

The facial artery has numerous branches, which can be classified as cervical and facial branches. Of the two major cervical branches, the ascending palatine artery and the submental artery, the latter is more likely to be involved in mandibular implant procedures. The submental artery branches off the facial artery before the facial artery rounds the mandibular bony border and swings upward into the face. The main branch of the submental artery passes anteriorly with the mylohyoid nerve and supplies lymph nodes in the submandibular triangle, the anterior belly of the di-gastric muscle, and the mylohyoid muscle. Near the chin, a terminal branch of the submental artery curves sharply upward and anastamoses within the soft outer tissues of the face with branches of the inferior labial artery, another branch of the facial artery.

The submental artery is of particular interest because when it substitutes the sublingual artery proper, it can be accidentally severed during oral surgery. If the hemorrhage cannot be stopped locally, the operator must determine whether the "sublingual" artery is being supplied by the submental or the lingual artery. Either must be ligated, in the case of the submental artery by ex-posing the facial artery where it crosses the lower border of the mandible and following it posteriorly to where it gives rise to the submental artery in the region of the superior anterior portion of the submandibular gland.

In the majority of cases, the only other branch of the facial artery that might be injured during oral surgery or working with sharp implements or instruments in the mouth is that segment of the ascending facial artery running through the cheek at the level of the inferior vestibular fornix in the region of the first mandibular molar. If an instrument slips and cuts the cheek in this region, severing the facial artery, it may be necessary to stop bleeding where the artery swings around the lower border of the mandible in front of the masseter muscle. This focal point is fairly easy to locate by palpation. The patient clenches his jaw, making the masseter more prominent, and the dentist feels immediately in front of the muscle for the pulse, which is fairly strong. If com-

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