A double-blind, clinical evaluation of facial augmentation treatments: a comparison of PRI 1, PRI 2, Zyplast® and Perlane®

Jeff Downie, Zhili Mao, Tsz-Wai Rachel Lo, Sarah Barry, Mitchum Bock, J. Paul Siebert, Adrian Bowman, Ashraf Ayoub

Research output: Contribution to journalArticlepeer-review

25 Citations (Scopus)


Background: Facial wrinkles are caused by weakening of the sub-dermal collagen support layer. Dermal fillers can be used to treat wrinkles, and this double-blind, randomised, single-centre study compared four fillers: PRI 1, PRI 2 (both porcine collagen), Zyplast? (purified bovine collagen) and Perlane? (cross-linked hyaluronic acid gel). Methods: 79 females (aged 25?55 years) with wrinkles in the upper lip line border were randomised to PRI 1 (19 patients), PRI 2 (19 patients), Perlane? (23 patients), Zyplast? (18 patients). Patients were assessed at 1 week and 1, 3, 6, 9 and 12 months using 2D images and by mathematically derived facial volume changes using 3D stereophotogrammetry. Results: All treatments produced larger, less wrinkled, more prominent lips. PRI 1, PRI 2 and Zyplast? showed similar lip volume gains, with Perlane? showing the greatest upper lip volume increase. All treatments were comparable for rates of decrease in upper lip volume post-treatment, however, Perlane? maintained higher lip volume gains at each time point. Investigators indicated PRI 1 was significantly easier to deliver than Zyplast?. Patient satisfaction scores were similar, though there was a trend towards greater dissatisfaction for PRI 1 and PRI 2 at month 9 (p = 0.052). Treatment was well-tolerated, with ?cold sore? being the most common adverse event. Conclusions: Results showed that PRI 1 and PRI 2 were comparable to Perlane? and Zyplast? as dermal fillers. Further rigorous studies are required to establish the performance of dermal fillers and patient acceptability. We propose the utilisation of stereophotogrammetry for assessment of volume changes.
Original languageEnglish
Pages (from-to)1636-1643
Number of pages8
JournalJournal of Plastic, Reconstructive & Aesthetic Surgery
Issue number12
Early online date4 Nov 2008
Publication statusPublished - 31 Dec 2009


  • dermal fillers
  • collagen
  • lip
  • ageing
  • stereophotogrammetry
  • 3D soft tissue analysis


Dive into the research topics of 'A double-blind, clinical evaluation of facial augmentation treatments: a comparison of PRI 1, PRI 2, Zyplast® and Perlane®'. Together they form a unique fingerprint.

Cite this