RESUMEN
The perioral region, being a site for many surgical reconstructive flaps, has become a target for many researches. The aim of the present study was to investigate the arterial supply of both upper and lower lips to provide an anatomical basis for alternatives of reconstruction methods in the perioral region. Forty two cadaveric face sides [21 preserved adult human cadavers] and 8 fresh face sides [4 stillbirths] were dissected after injection of the common carotid arteries with red latex. The facial artery and its branches, supplying both lips were dissected. The origin, course, branches, length, external diameter at their origin and anastomosis of both superior [SLA] and inferior [ILA] labial arteries were studied. The upper lip was constantly supplied by the SLA supplemented by an additional branch from the facial artery in only 10% of specimens. According to the mode of origin of the SLA, four patterns were observed. In type A [66%] the SLA was a side branch from the facial artery, type B [12%], it originated from the lateral nasal artery. It was one of the two terminal branches of the facial artery with either the ILA [type C, 12%], or the lateral nasal artery [type D, 10%]. The level of origin of the SLA was either above [72%], at [16%] or below [12%] the level of labial commissure. The mean distance between the origin of SLA and the labial commissure was 17.59 mm. The mean external diameter of the SLA at its origin was 1.69 mm. Its mean length was 52.19 mm. In 88% of specimens the SLA gave septal and anastomotic branches, while in 12% of specimens the septal branch originated from the facial artery above the origin of the SLA. The lower lip was supplied by the ILA in all specimens. Supernumerary branch from the facial artery proved to participate in the supply in 12% of specimens. The mean distance between the origin of ILA and the labial commissure was 27.5 mm while that for its external diameter at its origin was 1.86 mm. Its mean length was 60.81 mm. Both the SLA and the ILA coursed deep to the orbicularis oris muscle. The present results proved the great potentials for perioral flaps based on SLA or ILA. The vessels are long enough for rotation flaps. They can provide full thickness flap as they supply the entire thickness from skin to mucosa. They have a diameter large enough to allow microsurgical anastomosis. Free anastomosis between the labial arteries across the midline insures adequate nourishment of the donor lip