Randomized, controlled clinical trial to evaluate a xenogeneic collagen matrix as an alternative to free gingival grafting for oral soft tissue augmentation

J Periodontol. 2014 Oct;85(10):1333-41. doi: 10.1902/jop.2014.130692. Epub 2014 Mar 5.


Background: The standard of care for increasing keratinized tissue (KT) and vestibular area is an autogenous free gingival graft (FGG) and vestibuloplasty; however, there is morbidity associated with the harvest of autogenous tissue, and supply is limited. The purpose of this study is to determine if a xenogeneic collagen matrix (CM) might be as effective as FGG.

Methods: This study is a single-masked, randomized, controlled, split-mouth study of 30 patients with insufficient zones of KT (<2 mm). It uses a within-patient treatment-comparison design to establish non-inferiority of the test (CM) versus control (FGG) therapy. The primary efficacy endpoint was change in KT width (∆KT) from surgery to 6 months post-surgery. Secondary endpoints included traditional periodontal measures, such as clinical attachment level, recession, and bleeding on probing. Patient-reported pain, discomfort, and esthetic satisfaction were also recorded. Biopsies were obtained at 6 months.

Results: Surgery and postoperative sequelae were uneventful, with normal healing observed at both test and control sites. The primary outcome, ∆KT width at 6 months, did not establish non-inferiority of CM compared to FGG (P = 0.9992), with the FGG sites averaging 1.5 mm more KT width than CM sites. However, the amount of new KT generated for both therapies averaged ≥2 mm. Secondary outcomes were not significantly different between test and control sites. All site biopsies appeared as normal mucoperiosteum with keratinized epithelium. CM sites achieved better texture and color matches, and more than two-thirds of patients preferred the appearance of their CM sites.

Conclusion: With the proviso of sufficient KT (≈2 mm in width) and study goals of lower morbidity, unlimited supply, and patient satisfaction, CM appears to be a suitable substitute for FGG in vestibuloplasty procedures designed to increase KT around teeth.

Trial registration: ClinicalTrials.gov NCT01952301.

Keywords: Collagen; autologous; gingiva; heterologous; keratin; transplantation.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Biopsy
  • Collagen / therapeutic use*
  • Collagen Type I / therapeutic use
  • Collagen Type III / therapeutic use
  • Dental Plaque Index
  • Epithelium / pathology
  • Esthetics, Dental
  • Female
  • Follow-Up Studies
  • Gingiva / pathology
  • Gingiva / transplantation*
  • Gingival Hemorrhage / surgery
  • Gingival Recession / surgery
  • Gingivoplasty / methods*
  • Humans
  • Keratins
  • Male
  • Middle Aged
  • Pain Measurement
  • Patient Satisfaction
  • Periodontal Attachment Loss / surgery
  • Periodontal Index
  • Single-Blind Method
  • Treatment Outcome


  • Collagen Type I
  • Collagen Type III
  • Keratins
  • Collagen

Associated data

  • ClinicalTrials.gov/NCT01952301