The goal of this clinical trial is to evaluate local and systemic factors involved in palatal mucosal healing after Free Gingival Graft harvest in diabetic patients and to compare them with those in non-diabetic patients.

Diabetic and non-diabetic volunteers of both sexes aged ≥ 18 years with gingival recession may participate. The main questions it aims to answer are:

1. If the palatal wound healing (area of the wound) and percentage of wound epithelialization are different in diabetics compared to non-diabetics.
2. If different factors, such as the oral microbiome, inflammatory markers, and others, are associated with the clinical outcome.

Participants will be asked:

• Receive the procedure to treat their gingival recession defects
• To attend follow-up visits at 7, 14, 30, and 90 days after treatment.
• To provide different biological samples
• To answer different questionnaires.

Inclusion Criteria:

• aged ≥ 18 years;
• non-diabetic and diabetic patients (HbA1c>7% (American Diabetes Association 2025) managed with oral hypoglycemic agents or insulin;
• in the need of gingival recession treatment (RT1) in upper or lower arches with identifiable or restored cement-enamel junction (CEJ);
• periodontal stable (BoP ≤25%)(Lang et al. 2003);
• no morphological or pathological conditions in the palatal mucosa.

Exclusion Criteria:

• patients with cardiovascular, blood dyscrasias, and immunodeficiency that contraindicate surgical procedures;
• taking medications known to interfere with the wound healing process or that contraindicate the surgical procedure;
• Pregnancy/lactation (assessed via self-report);
• current opportunistic oral lesions that mainly colonize the palate region;
• subjects that have taken antibiotics within the last 3 months or need for antibiotic prophylaxis;
• prisoners;
• signs or symptoms of active extra-oral head and neck infection (swelling) as determined by a dentist at the time of evaluation;
• subjects who cannot read or speak English or Spanish, and do not agree to having the assistance of an interpreter

De-identified individual participant data (IPD) underlying the results reported in this study, including demographic variables, baseline characteristics, clinical measurements, outcome variables, and relevant covariates. may be made available upon a reasonable request.