Aim: To define immunophenotypes of stromal inflammatory and endothelial cells and fibroblasts 3-months post-augmentation of the peri-implant soft tissue using a porcine cross-linked collagen matrix (VCMX). Methods: Peri-implant soft tissue samples were obtained from 12 patients at the lining mucosa (LM) - masticatory mucosa (MM) junction, before and at 3-months post-augmentation. Immunohistochemical stains for identification of inflammatory cells [T (CD3) and B (CD20) lymphocytes, plasma cells (CD138)], macrophages (CD68-pro-inflammatory, CD163-anti-inflammatory/reparative), endothelial cells (CD31, CD34) and fibroblasts (CD90, TE-7), were performed. Differences in the mean positively-stained cells pre- and post-augmentation was analyzed by Wilcoxon Signed-Rank Test. Results: CD31+ endothelial cells showed increased mean numbers in MM2 compared to MM1 (p=0.025) and in LM2 compared to LM1 (p=0.047). CD163+ anti-inflammatory macrophages showed mean numbers in MM2 higher than MM1 (p=0.021) and in LM2 than LM1 (p=0.012). All other cell phenotypes showed insignificant changes between pre- and post-augmentation. Conclusion: This molecular study provided novel insight on the frequency of phenotypes of stromal cells in the wound healing process 3-months post-augmentation with VCMX, with anti-inflammatory CD163+ macrophages being predominant. This should be further investigated in order to find novel therapeutic approaches to modulate and promote the VCMX-related healing process.