Strip Graft w/ Xenogeneic Matrix vs Free Gingival Graft for the Augmentation of Peri-implant Keratinized Mucosa
The primary objective of this study is to compare changes in peri-implant keratinized mucosa (PIKM) following the application of apically repositioned flap (ARF) using a combination of a Strip graft and a Xenogeneic matrix, or with a free gingival graft (FGG), in implants in the second stage with <2 mm of PIKM.

Additionally, as a secondary objective, the investigators compare postoperative blood supply in both recipient and donor sites based on the type of graft obtained. Meanwhile, the investigators evaluate differences between the two groups concerning microcirculation values (perfusion units, PU), soft tissue thickness (STT), volume change, vestibular depth, as well as clinical, aesthetic, and patient-reported outcome measures (PROMS).
- EligibilityCriteria: Inclusion Criteria:  Patients older than 18 years Short-span dental implants in the mandible at second stage with inadequate PIKM (<2 mm) with at least one adjacent tooth mesially Periodontally healthy patients with a pristine or reduced periodontium Plaque index (FMPS) less than 20%.  Exclusion Criteria:  Compromised general health status that contraindicates study procedures (≥ASA III); Drug or alcohol abuse; Smoking of > 10 cigarettes per day; Chronic use of corticosteroids, NSAIDs or immunomodulators (any type or dose); Pregnant or lactating women; History of previous mucogingival surgeries in the area of interest - HealthyVolunteers: Accepts Healthy Volunteers - Gender: All - MinimumAge: 18 Years - MaximumAge: 80 Years - StdAgeList: Adult, Older Adult