The Effectiveness of Nano Bio Fusion Gingival Gel (NBF) on Wound Healing at the Palate (Donor Site) After Soft Tissue Graft Surgery Compared to Placebo Gel.

A sample size of 36 subjects, with treated 18 sites in each group should be sufficient to detect a mean difference of 1 mm of the wound area between groups. Efforts will be made to balance the number of men and women in each group (if possible).

The participants will be recruited from patients coming to dental teaching clinics at Jordan University of Science and Technology. The patients will be randomly assigned into 2 groups using computer generated randomization sequence:

Group 1: placebo gel Group 2: NBF gel

The study's purpose and procedures will be clearly communicated to all patient. Prior to examination and treatment, each participant must sign a consent form.

Patients who require a soft tissue surgery to cover gingival recession around teeth, to modify the phenotype where there is a thin gingival tissue, or to increase the width and thickness of soft tissue will be included in the study. The soft tissue graft should be obtained from the palatal donor site by free gingival graft or depithelized connective tissue graft, leaving an open wound in the palate (around 3×6 mm size) that is going to heal by secondary intesntion.

After the procedure, patients will be instructed to use the gel 4 times a day for 4 weeks by applying it to the wound and massaging the area. It will be provided in a small opaque tube. One tube should be used each day. The clinician and the patient will be blinded to the type of gel used. Another doctor or dental assistant will be responsible for dispencing the gel to the patient according to the randomization sequence and the code sheet.

Oral hygiene measures will be prohibited for the first 2 weeks in the surgical area only to not disturb the wound healing. Patients should follow their oral hygiene routine for the rest of the teeth. They will be instructed to use 0.2% chlorhexidine mouth wash twice a day for 2 weeks after surgery.

The study will last for one month for each patient. Each patient will be assessed immediately before and after the surgery and on days (0, 1, 2, 4, 7, 15, 21, 30). Clinical photographs will be taken at each time point.

Wound fluid samples (WF) will be collected at the incision area immediately after surgery and wound closure (day 0) and on days (1, 2, 4, 7). Main inflammotry mediators will be assessed.

Study steps:

• T0(intervention): Pt will sign the consent form. Sof tissue graft surgery will be performed and the graft will be obtained from the palate. The surgery is not performed by one periodontist, but the assessment and measurements are done by the same blinded examiner.

• T1 (24 hours after the surgery), T2 (2 days after the surgery), T3 (4 days after the surgery), T4 (7 days after the surgery), T5 (15 days after the surgery), T6 (21 days after the surgery), T7 (30 days after the surgery): The wound will be measured to record all the primary and secondary outcomes. The exception is made for the collection of wound fluid samples on days 15, 21 and 30. As the wound will be probably closed by then, samples will not be collected, unless there is delayed wound healing and the fluid can be drawn from the wound.

Clinical photos will be taken before surgery and anesthesia, immediately after surgery and the rest of time points.

• Application of NBF gel after soft tissue graft surgery (Drug), also known as phenotype modification, recession coverage, free gingival graft, connective tissue graft, coronal position flap, subepithelial connective tissue graft, tunnelling, lateral position flap: After the surgery, patients will be instructed to apply the NBF gel to the donor site on the palate for four times daily for 4 weeks. If there is a vertical releasing incision in the recipient site, the gel will be applied along that incision too. The first application will be performed immediately after surgery by the investigator using a sterile cotton applicator.
• Application of placebo gel after soft tissue graft surgery (Other), also known as phenotype modification, recession coverage, free gingival graft, connective tissue graft, coronal position flap, subepithelial connective tissue graft, tunnelling, lateral position flap: After the surgery, patients will be instructed to apply the placebo gel to the donor site on the palate for four times daily for 4 weeks. If there is a vertical releasing incision in the recipient site, the gel will be applied along that incision too. The first application will be performed immediately after surgery by the investigator using a sterile cotton applicator.

Primary outcomes

• Wound area [On each follow up visit: T1 (24 hours after the surgery), T2 (2 days after the surgery), T3 (4 days after the surgery), T4 (7 days after the surgery), T5 (15 days after the surgery), T6 (21 days after the surgery), T7 (30 days after the surgery)]: The wound area of the palatal donor site will have a rectangular shape, and it will be measured in mm according to the following equation: Area = length × width UNC15 periodontal probe will be used to do the measurements at the greatest dimension horizontally and vertically. The site will be left to heal by secondary intension.

Secondary outcomes

• Early wound healing index (EWHI) [On each follow up visit: T1 (24 hours after the surgery), T2 (2 days after the surgery), T3 (4 days after the surgery), T4 (7 days after the surgery), T5 (15 days after the surgery), T6 (21 days after the surgery), T7 (30 days after the surgery)]: the amount of fibrin at the wound margin will be assessed using early wound healing index (EWHI). The index was used to assess healing after papilla preservation flap. It will be modified to use at the vertical releasing incision of the recipient site according to the following criteria: 1. complete flap closure-no fibrin line at the incision line 2. complete flap closure-fine fibrin line at the incision line 3. complete flap closure-fibrin clot at the incision line 4. incomplete flap closure-partial tissue necrosis at the incision line 5. incomplete flap closure-complete tissue necrosis at the at the incision line
• Present or abscent (Yes/no): [On each follow up visit: T1 (24 hours after the surgery), T2 (2 days after the surgery), T3 (4 days after the surgery), T4 (7 days after the surgery), T5 (15 days after the surgery), T6 (21 days after the surgery), T7 (30 days after the surgery)]: 1. Pus discharge 2. Bleeding on palpation 3. Tenderness on palpation 4. Presence of granulation tissue 5. Scar (yes/no……if yes, wider or lesser than 2 mm, contour: regular or irregular)
• Erythema, redness + edema, swelling [On each follow up visit: T1 (24 hours after the surgery), T2 (2 days after the surgery), T3 (4 days after the surgery), T4 (7 days after the surgery), T5 (15 days after the surgery), T6 (21 days after the surgery), T7 (30 days after the surgery)]: mild <50% of the wound area, moderate 50%, severe >50%.
• Epithelization and exposure of CT [On each follow up visit: T1 (24 hours after the surgery), T2 (2 days after the surgery), T3 (4 days after the surgery), T4 (7 days after the surgery), T5 (15 days after the surgery), T6 (21 days after the surgery), T7 (30 days after the surgery)]: partial or complete epithelization
• Incision margins [On each follow up visit: T1 (24 hours after the surgery), T2 (2 days after the surgery), T3 (4 days after the surgery), T4 (7 days after the surgery), T5 (15 days after the surgery), T6 (21 days after the surgery), T7 (30 days after the surgery)]: measured for the vertical incsion on the recipient site if present. It will be recorded as: merged, in contact or in distance.
• Patient reported outcome measure (PROM) [On each follow up visit: T1 (24 hours after the surgery), T2 (2 days after the surgery), T3 (4 days after the surgery), T4 (7 days after the surgery), T5 (15 days after the surgery), T6 (21 days after the surgery), T7 (30 days after the surgery)]: Pain intensity: will be recorded on a visual analogue scale from 1-10. The higher the number the more the pain. * Duration: min, hour, whole day * Nature: continuous or intermittent - Consumption of Analgesics: Patients will be instructed to use 2 tabs of paracetamol 500 mg in case they feel pain. They should not use any other type of analgesics as it might affect the healing and inflammation. They will be requested to record the number of tablets and the times they were taken
• cytokine measurement using ELISA test [Immediately after surgery and wound closure (day 0) and on days (1, 2, 4, 7). They will not be collected at days 15, 21, and 30 as the wound should be closed by then, unless there is delayed wound healing and the fluid can be collected from the wound.]: Wound fluid samples (WF) will be collected from the palatal donor site and at the vertical incision using sterile paper points. Levels of cytokines (IL-1β, TNF-α, IL-6, IL-10) will be determined with Enzyme-Linked immunosorbent Assay test (ELISA) following the manufacturer's instructions.

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

Inclusion Criteria:

1. Patients with gingival recession that is indicated for root coverage or need for phenotype modification.
2. 18 years or older.
3. absence of systemic disease
4. Non-smoker
5. No use of antibiotics, corticosteroids, anti-inflammatory medication or hormones in the past 3 months

Exclusion Criteria:

1. Pregnant or lactating woman.
2. patients with immune or systemic diseases.
3. Patients with an allergy to any ingredient in the gel.

• Lana Bader, DClinDent Perio, Study director, Jordan University of Science and Technology
• Rand Aldurra, MClinDent Perio, Principal investigator, Jordan University of Science and Technology