title: Objective Analysis of Poly-L-Lactic Acid Injection Efficacy in Different Settings.
abstract: BACKGROUND
  Poly-L-lactic acid (PLLA) filler is known to have continuous volume effect.
  
  
  OBJECTIVE
  The objective of this study is to analyze objective volume effect of PLLA in different settings of injection schedule on the cheek.
  
  
  METHODS
  A split-face, evaluator-blind randomized study in 24 volunteers was conducted. One side was injected 3 times with 4 cc dose and the other side was injected 2 times with 6 cc dose per visit. Facial volume loss scale (FVLS) and Vectra were evaluated.
  
  
  RESULTS
  Measured average FVLS showed statistically significant improvement both in 3 and 2 times injection sides and maintained efficacy until 12 months. Vectra showed volume difference (cc) between before and after injection. In 3 times injection side, it was increased 2.12 (after 1 month) to 3.17 (after 12 months). In 2 times injection side, it was increased 2.26 (after 1 month) to 3.19 (after 12 months). Gradual volume improvement over 12 months was statistically significant in both sides. There was no statistically significant difference between 3 and 2 times injection in FVLS and Vectra. There was no severe adverse event.
  
  
  CONCLUSIONS
  Poly-L-lactic acid has continuous volume effect and there was no significant difference by injection times at the same total injection volume.
authors.affiliation: *Department of Dermatology, Seoul National University College of Medicine and Seoul National University Bundang Hospital, Seongnam, Korea; †Modelo Clinic, Seoul, Korea; ‡College of Medicine, Emory University, Atlanta, Georgia.
authors.forename: Sang-Young
authors.initials: SY
authors.lastname: Byun
authors.forename: Koo-Il
authors.initials: KI
authors.lastname: Seo
authors.forename: Jung-Won
authors.initials: JW
authors.lastname: Shin
authors.forename: Soon-Hyo
authors.initials: SH
authors.lastname: Kwon
authors.forename: Mi-Sook
authors.initials: MS
authors.lastname: Park
authors.forename: Joshua
authors.initials: J
authors.lastname: Lee
authors.forename: Kyoung-Chan
authors.initials: KC
authors.lastname: Park
authors.forename: Jung-Im
authors.initials: JI
authors.lastname: Na
authors.forename: Chang-Hun
authors.initials: CH
authors.lastname: Huh
mesh_terms: D000328:Adult; D000368:Aged; D001672:Biocompatible Materials / Q000008:administration & dosage*; D002610:Cheek; D003357:Cosmetic Techniques; D005260:Female; D006801:Humans; D007267:Injections; D019344:Lactic Acid / Q000008:administration & dosage*; D008297:Male; D008875:Middle Aged; D011091:Polyesters; D011108:Polymers / Q000008:administration & dosage*; D016037:Single-Blind Method; D015595:Skin Aging / Q000187:drug effects*
chemical_list: D001672:Biocompatible Materials; D011091:Polyesters; D011108:Polymers; D019344:Lactic Acid; C033616:poly(lactide)