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 3months.

Abstract

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). 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 90days (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. The median linear changes from BL to FU-90 in the crestal ROI amounted to 0.175mm (0.06; 0.51) for VCMX (p=0.002 over time) and to 0.51mm (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 0.59mm (0.26; 1.06) for VCMX (p=0.002) and 0.94mm (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. VCMX and SCTG can be used for soft tissue augmentation at implant sites resulting in an at least short-term increase in volume.