Changes in Volume of Lips in 3D-Analysis and Projection of Lips in Sonography After Injection of Particle Type Hyaluronic Acid Filler Utilizing a 9-Point Injection Technique

Abstract

Abstract Background Lip augmentation procedure with hyaluronic acid (HA) fillers can make patients younger with more attractive. After the injection on the lips, the result is temporary. Physicians and patients wonder how long the HA-filler last on the lips. Objectives The main goal of this study is to determine how much volume of HA is reduced after injection on the lips utilizing a “9-point” injection technique. Methods In this prospective study, 25 women were injected using HA filler and evaluated using non-invasive 3D-scanner analysis before, 1-hour, 1-week, 1-month, 6-month and 9-months after injection. The changes in projection of lips were evaluated using sonography. The patients were treated as usual manner in a single clinic. Using 29-gauge needle, 20mg/ml of HA-filler was injected into the lips. Default injection amount was 1cc. HA filler was injected submucosally using linear thread and fanning technique. Results 23 patients were followed up. Mean age was 34.8 years(range:20–48years). The volume of lips became 181.34%(±61.14) at 1-hour, 91.18%(±10.12) at 1-week, 75.09%(±11.02) at 1-months, 55.36%(±10.48) at 6-months, and 39.21%(±4.54) at 9-months. The projection of upper lips areas increased 25.3% at 1-hour, 22.8% at 1-week, 17.7% at 1-months, 14.8% at 6-months, 11.5% at 9-months in sonography. The projection of lower lips areas increased 23.1% at 1-hour, 20.7% at 1-week, 15.9% at 1-months, 13.9% at 6-months, 10.6% at 9-months in sonography Conclusions Lip augmentation with HA showed improved shape during 9-months. The volume of HA decreased at a constant rate after injection, except for the first week. Injected HA was absorbed at a constant rate, and more than half was absorbed after 9 months utilizing a “9-point” injection technique.