title: Soft tissue volume augmentation by the use of collagen-based matrices: a volumetric analysis.
abstract: OBJECTIVE
  The aim was to test whether or not soft tissue augmentation with a newly developed collagen matrix (CM) leads to volume gain in chronic ridge defects similar to those obtained by an autogenous subepithelial connective tissue graft (SCTG).
  
  
  METHODS
  In six dogs, soft tissue volume augmentation was performed by randomly allocating three treatment modalities to chronic ridge defects (CM, SCTG, sham-operated control). Impressions were taken before augmentation (baseline), at 28, and 84 days. The obtained casts were optically scanned and the images were digitally analysed. A defined region of interest was measured in all sites and the volume differences between the time points were calculated.
  
  
  RESULTS
  The mean volume differences per area between baseline and 28 days amounted to a gain of 1.6 mm (CM; SD+/-0.9), 1.5 mm (SCTG; +/-0.1), and a loss of 0.003 mm (control; +/-0.3). At 84 days, the mean volume differences per area to baseline measured a gain of 1.4 mm (CM; +/-1.1), 1.4 mm (SCTG; +/-0.4), and a loss of 0.3 mm (control; +/-0.3). The differences between CM and SCTG were statistically significant compared with control at 28 and 84 days (p<0.001).
  
  
  CONCLUSIONS
  Within the limits of this animal study, the CM may serve as a replacement for autogenous connective tissue.
authors.affiliation: Clinic for Fixed and Removable Prosthodontics and Dental Material Science, University of Zurich, Zurich, Switzerland. daniel.thoma@zzmk.uzh.ch
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Thoma
authors.forename: Ronald E
authors.initials: RE
authors.lastname: Jung
authors.forename: David
authors.initials: D
authors.lastname: Schneider
authors.forename: David L
authors.initials: DL
authors.lastname: Cochran
authors.forename: Andreas
authors.initials: A
authors.lastname: Ender
authors.forename: Archie A
authors.initials: AA
authors.lastname: Jones
authors.forename: Christoph
authors.initials: C
authors.lastname: Görlach
authors.forename: Lorenz
authors.initials: L
authors.lastname: Uebersax
authors.forename: Ursula
authors.initials: U
authors.lastname: Graf-Hausner
authors.forename: Christoph H F
authors.initials: CH
authors.lastname: Hämmerle
mesh_terms: D000540:Alveolar Ridge Augmentation / Q000379:methods*; D000818:Animals; D003094:Collagen / Q000627:therapeutic use*; D003238:Connective Tissue / Q000637:transplantation*; D004285:Dogs; D005109:Extracellular Matrix / Q000637:transplantation*; D005893:Gingivoplasty / Q000379:methods; D008297:Male; D011897:Random Allocation
chemical_list: D003094:Collagen