Ultrasound may guide gum surgery by revealing hidden blood vessels

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: 1. Age ≥ 18 years. 2. Presence of at least one mandibular gingival recession defect (RT1 or RT2) at an anterior, canine, or premolar tooth with an indication for treatment using a coronally advanced flap (CAF). 3. Good oral hygiene: full-mouth plaque score (FMPS) ≤ 20% and full-mouth bleeding score (FMBS) ≤ 20%. 4. Periodontal stability: no active or untreated periodontitis; probing depths ≤ 4 mm at the study site. 5. Ability to undergo pre-operative and post-operative ultrasound imaging and clinical documentation. 6. No contraindication to local anaesthesia or minor periodontal surgery. 7. Ability and willingness to comply with all scheduled follow-up visits (days 7, 14, 30 and 4 months). 8. Provision of written informed consent prior to any study-related procedures. Exclusion Criteria: 1. Systemic contraindications to minor oral surgery (ASA ≥ III, uncontrolled diabetes mellitus \[HbA1c \> 7.5%\], immunosuppressive therapy, bleeding disorders, or coagulation abnormalities). 2. Current antithrombotic therapy that cannot be safely managed peri-operatively according to the treating clinician. 3. Smoking more than 10 cigarettes per day or equivalent vaping within the previous 6 months. 4. Previous mucogingival surgery, traumatic scarring, or soft-tissue grafting in the mandibular anterior or premolar region that could interfere with vascular assessment. 5. Active oral infection or acute gingival inflammation at or near the study site. 6. Untreated caries, endodontic pathology, or restorative defects at the involved tooth. 7. Pregnancy or lactation. 8. Known allergy or hypersensitivity to ultrasound gel or (if applied) indocyanine green (ICG) or iodine. 9. Liver dysfunction or other medical contraindication precluding ICG use (relevant only if optional perfusion imaging is performed). 10. Inability or unwillingness to comply with study procedures or follow-up schedule.