Randomized controlled clinical study comparing a volume-stable collagen matrix to autogenous connective tissue grafts for soft tissue augmentation at implant sites: linear volumetric soft tissue changes up to 3 months

J Clin Periodontol. 2017 Apr;44(4):446-453. doi: 10.1111/jcpe.12697. Epub 2017 Feb 11.


Aim: To test whether or not the use of a volume-stable collagen matrix (VCMX) results in soft tissue volume increase at implant sites non-inferior to an autogenous subepithelial connective tissue graft (SCTG).

Methods: In 20 patients, soft tissue augmentation at implant sites was performed using VCMX or SCTG. Casts obtained prior to augmentation (BL), at 30 (FU-30) and 90 days (FU-90) were digitized and transferred to stereolithography (STL) files. BL, FU-30 and FU-90 STL files were superimposed and linear volumetric changes evaluated in crestal and buccal regions of interest (ROI). Descriptive analysis was computed for both groups and a test for non-inferiority was performed.

Results: The median linear changes from BL to FU-90 in the crestal ROI amounted to 0.175 mm (0.06; 0.51) for VCMX (p = 0.002 over time) and to 0.51 mm (0.23; 0.94) for SCTG (p = 0.129). The differences between the two groups were not significant (p = 0.287). The respective values in the buccal ROI were 0.59 mm (0.26; 1.06) for VCMX (p = 0.002) and 0.94 mm (0.66; 1.13) for SCTG (p = 0.004). The differences between the two groups were not significant (crestal: p = 0.287; buccal: p = 0.534). Non-inferiority could be concluded for VCMX compared to SCTG for both ROI.

Conclusion: VCMX and SCTG can be used for soft tissue augmentation at implant sites resulting in an at least short-term increase in volume.

Keywords: collagen-based matrix; dental implant; soft tissue augmentation; soft tissue volume; subepithelial connective tissue graft.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Collagen*
  • Connective Tissue / transplantation*
  • Dental Implants*
  • Female
  • Gingiva / anatomy & histology
  • Gingiva / surgery*
  • Humans
  • Male
  • Middle Aged
  • Organ Size
  • Time Factors


  • Dental Implants
  • Collagen