portantly to the implantologist, the sublingual artery supplies the mylohyoid muscle. Within the mylohyoid muscle, the sublingual artery anastamoses with branches of the submental artery, a branch of the facial artery.

In some cases, the major arterial supply to the sublingual regions derives not from that branch of the lingual artery called the sublingual artery, but from a branch of the submental artery. Typically the paths of the "true" sublingual and the submental arteries run almost parallel, the sublingual near the inner and upper surface of the mylohyoid muscle, and the submental on the outer and inferior surface of the muscle. These arteries freely anastamose, and a well developed connecting branch of either artery may perforate the muscle and assume the function of the other artery. This potential — replacement of the sublingual artery by one or more branches of the submental — occurs when the sublingual artery is small, insignificant, or absent, and is clinically significant. A sharp instrument or rotating disc may slip and cut the floor of the mouth, severing the artery.

If the accident occurs in the premolar or first molar region, there may be considerable bleeding. Local clamping, the first method of choice, is difficult, and the operator must stop the bleeding by ligating the artery feeding the injured artery. The lingual artery, which must be approached through the submandibular triangle — bounded by the lower border of the mandible and by the two bellies of the digastric muscle, usually feeds the injured sublingual artery. However, the operator should recognize that he may have severed a branch of the submental artery, and treat the situation accordingly.

The facial artery may originate separately from the external carotid artery or arise from a short trunk shared with the lingual artery, the linguofacial trunk. When it arises directly from the external carotid, the more typical situation, it arises just below the posterior belly of the digastric muscle, or slightly higher, in which case the muscle covers its origin. It runs obliquely upward and forward, entering the submandibular triangle where it is covered by the submandibular salivary gland. At or near the superior border of the gland, in the region of the mandibular angle, the artery turns sharply laterally, obliquely anteriorly, and slightly downward toward the angle of the mandible. Here, on the mandibular angle in front of the anterior border of the masseter muscle, the facial artery swings around the bone and upward into the soft tissues of the face. At this point the pulse can easily be felt.

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