Open Access

Background: The present study aimed to assess the three‐dimensional changes following soft tissue augmentation using free gingival grafts (FGG) at implant sites over a 3‐month follow‐up period. Methods: This study included 12 patients exhibiting deficient keratinized tissue (KT) width (i.e., <2 mm) at the vestibular aspect of 19 implants who underwent soft tissue augmentation using FGG at second stage surgery following implant placement. Twelve implants were considered for the statistical analysis (n = 12). The region of interest (ROI) was intraorally scanned before surgery (S0), immediately post‐surgery (S1), 30 (S2) and 90 (S3) days after augmentation. Digital scanned files were used for quantification of FGG surface area (SA) and converted to standard tessellation language (STL) format for superimposition and evaluation of thickness changes between the corresponding time points. FGG shrinkage (%) in terms of SA and thickness was calculated between the assessed time points. Results: Mean FGG SA amounted to 91 (95% CI: 63 to 119), 76.2 (95% CI: 45 to 106), and 61.3 (95% CI: 41 to 81) mm2 at S1, S2, and S3, respectively. Mean FGG SA shrinkage rate was 16.3% (95% CI: 3 to 29) from S1 to S2 and 33% (95% CI: 19 to 46) from S1 to S3. Mean thickness gain from baseline (S0) to S1, S2, and S3 was 1.31 (95% CI: 1.2 to 1.4), 0.82 (95% CI: 0.5 to 1.12), and 0.37 (0.21 to 0.5) mm, respectively. FGG thickness shrinkage was of 38% (95% CI: 17.6 to 58) from S1 to S2 and 71.8% (95% CI: 60 to 84) from S1 to S3. Dimensional changes from S1 to S3 were statistically significant, P <0.017. Soft tissue healing was uneventful in all patients. Conclusions: The present three‐dimensional assessment suggests that FGG undergo significant dimensional changes in SA and thickness over a 3‐month healing period.

Aim: To assess volumetric tissue changes at peri‐implantitis sites following combined surgical therapy of peri‐implantitis over a 6‐month follow‐up period. Materials and Methods: Twenty patients (n = 28 implants) diagnosed with peri‐implantitis underwent access flap surgery, implantoplasty at supracrestally or bucally exposed implant surfaces and augmentation at intra‐bony components using a natural bone mineral and application of a native collagen membrane during clinical routine treatments. The peri‐implant region of interest (ROI) was intra‐orally scanned pre‐operatively (S0), and after 1 (S1) and 6 (S2) months following surgical therapy. Digital files were converted to standard tessellation language (STL) format for superimposition and assessment of peri‐implant volumetric variations between time points. The change in thickness was assessed at a standardized ROI, subdivided into three equidistant sections (i.e. marginal, medial and apical). Peri‐implant soft tissue contour area (STCA) (mm2) and its corresponding contraction rates (%) were also assessed. Results: Peri‐implant tissues revealed a mean thickness change (loss) of −0.11 and −0.28 mm at 1 and 6 months. S0 to S1 volumetric variations pointed to a thickness change of −0.46, 0.08 and 0.4 mm at marginal, medial and apical regions, respectively. S0 to S2 analysis exhibited corresponding thickness changes of −0.61, −0.25 and −0.09 mm, respectively. The thickness differences between the areas were statistically significant at both time periods. The mean peri‐implant STCA totalled to 189.2, 175 and 158.9 mm2 at S0, S1 and S2, showing a significant STCA contraction rate of 7.9% from S0 to S1 and of 18.5% from S0 to S2. Linear regression analysis revealed a significant association between the pre‐operative width of keratinized mucosa (KM) and STCA contraction rate. Conclusions: The peri‐implant mucosa undergoes considerable volumetric changes after combined surgical therapy. However, tissue contraction appears to be influenced by the width of KM.