Palatal Wound Healing After Free Gingival Graft Harvest in Diabetic Patients: A Clinical Trial

• Free gingival graft (Procedure): Volunteers with gingival recession will be treated with coronally advanced flap and connective tissue graft (CTG). The CTG will be obtained by harvesting a 2-mm thick free gingival graft (FGG), measuring 15 × 5 mm from the palatal area between the distal of the canine and the mesial aspect of the first molar. The palatal wound will be evaluated.

Primary outcomes

• Remaining wound area (RWA) [3 months]: The RWA will be measured in square millimeters using software (Image J- NIH, Bethesda, Maryland, USA) at baseline (trans-operative) and 1, 2, 4, and 12 weeks after the surgery

Secondary outcomes

• Epithelialization - EPT [3 months]: Standardized photographs will be taken after a disclosure solution (Disclosing Agent, Dentsply, Charlotte, NC, USA) application in the wound area at 1,2, 4, and 12 weeks postoperatively. The epithelialized area was calculated as the percentage of the original wound area using software (Image J- NIH, Bethesda, Maryland, USA) calibrated with a measuring scale in the palate.
• Insomnia Severity Index Survey [Baseline and up to 4 weeks]: The insomnia survey scores range from 0 to 28 with a higher score indicating greater insomnia.
• Tissue thickness - TT [3 months]: An endodontic spreader with a stop rubber will be inserted at the center of the wound area until reaching the bone. The distance between the instrument tip and the rubber stopper will be measured with a digital caliper
• Inflammatory markers [2 weeks]: The wound exudate may be collected 1 week after the procedure. Two paper strips (periopaper, Oraflow, Inc.) per wound will be individually placed and left in position for 40-60 s each. Before sampling, the wound will be gently rinsed and dried using water and an air spray. Relative isolation will then be performed immediately. If contamination with blood or saliva occurs, the paper strip will be discarded, and a new sample will be collected. In sequence, both paper strips will be placed into Eppendorf tubes and stored at -80º Celsius for further processing of inflammatory markers by Multiplex assay

Sex: All, ages: 18 Years to any, accepts healthy volunteers

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

• Miguel MMV, Mathias-Santamaria IF, Rossato A, Ferraz LFF, Rangel TP, Casarin RCV, Tatakis DN, Santamaria MP. Enamel matrix derivative effects on palatal mucosa wound healing: Randomized clinical trial. J Periodontal Res. 2021 Dec;56(6):1213-1222. doi: 10.1111/jre.12934. Epub 2021 Sep 19. PMID 34541683
• Santamaria MP, Mathias-Santamaria IF, Ferreira Bonafe AC, Gonzalez OA, Kirakodu S, Monteiro MF, Casarin RCV, Shaddox LM, Miguel MMV. Microbiome and Inflammatory Biomarkers Associated With Palatal Wound Healing. J Periodontal Res. 2025 Jul;60(7):664-675. doi: 10.1111/jre.13373. Epub 2025 Jan 13. PMID 39801488

• Mauro Pedrine Santamaria, DDS, Ms, PhD, Principal investigator, University of Kentucky