From the studies

From the studies

1) The facial artery branches into the superior labial artery just above the labial commissure. This artery ran 4.5 mm deep along the upper lip between the oral mucosa and the orbicularis oris muscle just above the vermilion-mucosa junction to anastomose with the opposing artery. The inferior labial artery originated as a common trunk along with the labiomental artery once the facial artery entered the oral vestibule deep to the platysma muscle. The main arterial trunk coursed along the alveolar border within the plane between the orbicularis oris muscle and the lip depressors. From the arterial trunk emanated the inferior labial artery, which accompanied the mental nerve to the lower lip. CONCLUSION:  The vermilion borders of the upper and lower lips are safe for superficial filler injection. All areas of the lower lip are safe because of the minute size of the ascending arteries. To achieve a full upper lip, filler should be injected into the middle body of the lip, thereby avoiding deep injection between the muscle layer and the mucosa, minimizing the risk of injury to the anastomotic arch of the superior labial arteries.

2) Considering arterial anatomy, the upper lip has a higher chance of arterial injury than the lower lip. The cannula/NEEDLE should not be inserted in the submucosa as it is recommended to evert the vermilion because both the superior and inferior labial arteries are located in the submucosa of the medial and middle segments of the vermilion in all specimens. CONCLUSION:  Awareness of the possibility of vascular injury is necessary during injections of the medial segments of the vermilion of the lips. Vermilion border and marginal injections are recommended for safe and effective lip augmentation. Deep injection around the oral commissure and submucosal injection of the medial and middle segments of the vermilion zone are prohibited because of the high risk of arterial injury.

3) ABSTRACT AND CONCLUSION The locations and distributions of the superior labial artery (SLA) and the inferior labial artery (ILA) relative to the vermilion border (VB). Based on the VB, the overall thicknesses of the upper and lower lips average to 9.4 ± 0.4 mm (mean ± SD) and 10.9 ± 0.7 mm, respectively. In most cases, the labial arteries are located in the wet mucosal layer on both the upper (35– 57%) and lower lips (28–55%), respectively. In the upper lip, the SLA is in the intramuscular layer in 20–45% of cases, making it the second most common type. At some of the measuring points, the SLA was observed more often in the intramuscular layer than in the wet mucosal layer. In the lower lip, the ILA is also located in the dry mucosa (5–27%). The dry–wet mucosal junction is unclear in the lip area, and the ILA is commonly observed at the dry–wet mucosal junction. The arterial depth is 5.3 ± 0.3 mm in the upper lip and 4.2 ± 0.4 mm in the lower lip. The SLA and ILA are evenly distributed over all parts of the oral mucosa. Injection procedures for lip augmentation should therefore use very superficial approaches.