Porcine Cross-Linked Collagen Matrix for Peri-Implant Vertical Soft Tissue Augmentation: A Randomized Prospective Observational Study

The mucosa height has always been of interest in modern implant dentistry to obtain biomimetic results. Papilla height, mucosa scalloping, and free mucosal margin level are crucial to achieve "pink aesthetics". The aim of this study was to investigate the vertical increase in the peri-implant soft tissues with a porcine cross-linked collagen matrix (Geistlich Fibro-Gide (R)). Methods: A total of 60 patients were divided into the following three groups: Group 1-patients who received porcine cross-linked collagen matrix for vertical soft tissue augmentation and a cover screw combined with a coronally advanced flap (CAF); Group 2-patients who received the collagen matrix combined with a healing abutment and CAF; Group 3 (control group)-patients who received a traditional surgical approach based on crestal incision and no collagen matrix as well as no CAF. Results: The average horizontal tissue thickness growth after 3 months was more effective for Group 1 (1.35 +/- 1.23 mm) compared to Group 2 (0.85 +/- 0.67 mm) and the control group (0.20 +/- 0.41 mm). The average tissue height growth was 1.05 +/- 1.39 mm for Group 1, 0.32 +/- 1.28 mm for Group 2, and -0.05 +/- 0.39 mm for the control group. Finally, the average increase in the band of keratinized mucosa was 0.60 +/- 1.23 mm for Group 1, -0.60 +/- 0.94 mm for Group 2, and 0.45 +/- 0.60 mm for the control group. Conclusions: The combination of the CAF, porcine cross-linked collagen matrix, and cover screw resulted in better clinical results compared to Group 2 and 3.