Ridge deformities can complicate prosthetic rehabilitation, especially in situations where optimal esthetic outcomes are desired. Simpler, less invasive and predictable treatments are needed in order to obtain soft tissue augmentation at edentulous ridges. Autogenous subepithelial connective tissue graft (SCTG) has always been regarded as the treatment of choice, but heterologous volume stable collagen matrix (VCMX) is emerging as a reliable alternative. The principal aim of the present RCT will be to compare the volumetric buccal soft tissue changes at edentulous areas after augmentation procedure using VCMX or SCTG. Parameters related to periodontal health at adjacent teeth and patient reported outcomes (PROMs) will be also assessed as secondary outcomes. Proving the non- inferiority of VCMX compared to SCTG would provide the specialists and general clinicians with an easier, less invasive and better tolerated technique for soft tissue augmentation at edentulous ridges and for improving aesthetic and cleansability of the prosthetic rehabilitation.

Inclusion Criteria:

• Intercalated mono-edentulous area ridge defects to be rehabilitated with fixed partial bridge
• At least 18 years old
• At least 6 months from tooth extraction at the study area.

Exclusion Criteria:

• Systemic diseases which could influence the outcome of the therapy (e.g. uncontrolled diabetes mellitus);
• Smoking ≥ 10 cigarettes a day;
• Pregnant or nursing women;
• Chronic use of corticosteroids or other anti-inflammatory or immune-modulator drugs;
• Patients who need use of medications affecting bone metabolism or oral mucosa;
• Presence of a congruous FDP at the edentulous area;
• History of soft tissue augmentation surgery in the study area;
• Active periodontitis
• Uncompliant patients