Gross anatomical classification of the courses of the human sublingual artery

The purpose of the present study was to classify the courses of the human sublingual artery. For this purpose, the arteries supplying the floor of the mouth and the tongue were gross anatomically investigated using 101 sides of 53 cadavers. The courses were divided into three categories: those passing medial or lateral to the hyoglossus (categories M and L) and that piercing the mylohyoid (category P); they were subdivided into five types. Category M had one type, regarded as the usual one, in which the lingual artery took the usual pattern of distribution. Categories L and P, in which the sublingual artery arose from the facial or submental artery, had the respective two types and were collectively regarded as the unusual type. Sixty-one and 36 of the 101 sides were of the usual and unusual types, respectively, the latter of which included 17 of category L and 19 of category P. The remaining four were variations of the lingual artery itself. On examining the types by gender, the usual type was more often found in females (75.6%), whereas the unusual type was more often found in males (48.1%). Bilateral occurrence of the same type was often found in both the usual type (77.4%) and the unusual type (65.0%). Existence of the sublingual artery branch significantly increased the thicknesses of the submental arteries. The classification proposed here will conceivably contribute to safer dental implant surgery and more accurate interpretation of angiographic images of arteries in the floor of the mouth.