Peri-Implant Soft Tissue Increase at Small Buccal Bone Dehiscences With Either Volume-Stable Collagen Matrix or Connective Tissue Graft: A Randomized Controlled Trial.

OBJECTIVES: This randomized clinical study compared the profilometric measurements of the buccal tissue volume at sites augmented using a volume-stable collagen matrix (VCMX) or connective tissue graft (CTG) simultaneously to implant placement in the presence of small buccal bone dehiscence (SBBD </= 3 mm). METHODS: Forty-four patients with SBBD were treated with soft tissue augmentation (STA) simultaneous to implant placement using VCMX or SCTG. Clinical measurements and 3D intraoral scans were collected prior to STA (BL), at 1, 3 months, and 1 year after prosthetic loading. Digital files were superimposed to compare profilometric volume on the buccal profile (primary outcome); peri-implant health, radiographic bone levels, and patient-reported outcome measures (PROMs) were also assessed. RESULTS: Both treatments achieved a significant STA at 3 months, with a slight decrease observed from 1 month. At 3 months, the mean increase was 1.07 mm (SD 0.22) for VCMX and 1.22 mm (SD 0.44) for the CTG group (p = 0.156). PROMs revealed a difference in the perception of the bleeding at day 1, pain at 2 and 3 days, and swelling at 3 days favoring VCMX (p < 0.05). At 1 year, no intergroup difference in probing pocket depth, bleeding, and recession was detected, but CTG provided higher stability than VCMX in terms of profilometric measurements (0.21 mm [SD 0.32] vs. -0.05 mm [SD 0.36], respectively; p = 0.014) and radiographic bone levels (0.09 mm [SD 0.65] vs. -0.34 mm [SD 0.70]; p = 0.038). CONCLUSION: For implant placement at posterior sites with small buccal bone dehiscences, CTG and VCMX resulted in an initially comparable volume augmentation and clinical parameters, with VCMX leading to better PROMs. At 1 year, CTG maintained slightly higher profilometric stability and bone levels. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT05466006 (https://classic. CLINICALTRIALS: gov/ct2/show/NCT05466006).