Effect of i-PRF and LLLT on Free Gingival Graft Shrinkage

The Effect of Injectable Platelet-Rich Fibrin and Low-Level Laser Therapy on Graft Shrinkage in Free Gingival Grafts: A Randomized Controlled Clinical Trial

This randomized clinical trial aims to evaluate whether injectable platelet-rich fibrin (i-PRF) and low-level laser therapy (LLLT) can reduce graft shrinkage after free gingival graft procedures. Free gingival grafts are commonly used to increase the width of keratinized tissue around teeth, but the graft often shrinks during healing. In this study, patients will receive standard free gingival graft surgery with or without additional i-PRF or laser therapy. The goal is to determine whether these treatments improve healing and help maintain the size of the graft.

Study Overview

• Status: Completed
• Conditions: Gingival Recession, Localized; Graft Shrinkage
• Intervention / Treatment: Procedure: Free Gingival Graft (FGG); Device: Low-Level Laser Therapy (LLLT); Biological: Injectable Platelet-Rich Fibrin (i-PRF)

Detailed Description

This randomized controlled clinical trial investigates the effects of injectable platelet-rich fibrin (i-PRF) and low-level laser therapy (LLLT) on the shrinkage of free gingival grafts (FGG) used to treat gingival recession. Free gingival grafting is commonly performed to increase the width of keratinized tissue around teeth, but shrinkage during healing can reduce clinical outcomes.

The study included 48 systemically healthy adult patients with Cairo Class I gingival recession in mandibular anterior teeth. Participants were randomly assigned to one of three groups: control (FGG alone), i-PRF (FGG + platelet-rich fibrin), or LLLT (FGG + low-level laser therapy). Ethical approval was obtained from the Clinical Research Ethics Committee of Inonu University (Protocol No: 2024/84), and all participants provided written informed consent. The study protocol was registered at ClinicalTrials.gov (NCT06744270) and conducted according to CONSORT 2010 guidelines.

All patients received preoperative periodontal treatment, including plaque removal and oral hygiene instructions. Free gingival grafts were harvested from the palatal region and adapted to the recipient site, then stabilized with sutures. In the i-PRF group, autologous platelet-rich fibrin gel was applied to the graft surface. In the LLLT group, laser therapy was applied immediately after surgery and on postoperative days 3, 5, 7, and 14. The control group received no additional treatment beyond standard grafting.

Postoperative care included use of a periodontal dressing, chlorhexidine mouthwash, analgesics as needed, and oral hygiene instructions after suture removal. Clinical evaluations included gingival recession depth, keratinized tissue height, probing depth, clinical attachment level, and graft area measurements at baseline, 1, 3, and 6 months. Edema, erythema, and patient-reported pain were also assessed during follow-up.

The primary outcome of the study was graft shrinkage, calculated as the percentage decrease in graft area over time. Secondary outcomes included clinical parameters and patient-reported postoperative morbidity. All measurements were performed by calibrated, blinded examiners to ensure reliability.

• Study Type: Interventional
• Enrollment (Actual): 48
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Kahramanmaraş, Turkey (Türkiye)
    • Kahramanmaraş Sütçü İmam University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Age > 18 years.
• Systemically healthy.
• Cairo Class I gingival recession in vital mandibular anterior incisors.
• No caries or restorations in the relevant teeth.
• Keratinized gingiva height < 2 mm in the included teeth.
• Plaque Index (PI) < 1.
• Gingival Index (GI) < 1.

Exclusion Criteria:

• Active periodontal disease or probing depth > 3 mm.
• Use of medications that could prevent surgery or affect wound healing.
• Pregnancy or breastfeeding.
• History of periodontal surgery in the working area.
• Active smokers.
• Current orthodontic treatment.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Control Group; Patients receive free gingival graft only without additional treatment.	Procedure: Free Gingival Graft (FGG); Standard free gingival graft procedure performed without additional treatments.
Experimental: i-PRF group; Patients receive free gingival graft with injectable platelet-rich fibrin applied to the graft surface.	Procedure: Free Gingival Graft (FGG); Standard free gingival graft procedure performed without additional treatments.; Device: Low-Level Laser Therapy (LLLT); Low-level laser therapy is applied to the graft site immediately after surgery and on postoperative days 3, 5, 7, and 14 to potentially improve healing and reduce graft shrinkage.
Experimental: LLLT Group; Patients receive free gingival graft with low-level laser therapy applied immediately after surgery and on postoperative days 3, 5, 7, and 14.	Procedure: Free Gingival Graft (FGG); Standard free gingival graft procedure performed without additional treatments.; Biological: Injectable Platelet-Rich Fibrin (i-PRF); Autologous platelet-rich fibrin gel is applied to the graft surface after free gingival graft surgery to potentially reduce graft shrinkage.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Graft Area Shrinkage (%)	Change in graft surface area, expressed as percentage shrinkage from baseline. Standardized clinical photographs taken at baseline and at postoperative 1, 3, and 6 months were analyzed using calibrated digital image analysis software (ImageJ). The graft borders were traced, and surface area (mm²) was calculated. Each measurement was repeated three times, and the mean value was used. Shrinkage percentage was calculated using the formula: Shrinkage % = [(baseline area - follow-up area) / baseline area] × 100.	Baseline, 1 month, 3 months, and 6 months postoperatively.
Root Coverage Percentage (%)	Percentage of root coverage obtained at 6 months. Root coverage was calculated from changes in gingival recession depth (RD) using the formula: Root Coverage % = [(baseline RD - RD at 6 months) / baseline RD] × 100. RD was defined as the distance from the CEJ to the gingival margin and measured using a manual periodontal probe.	Baseline and 6 months postoperatively.
Gingival Recession Depth (RD)	Change in gingival recession depth measured in millimeters.	Baseline, 1 month, 3 months, and 6 months postoperatively.
Keratinized Tissue Height (KTH)	Change in keratinized tissue height measured in millimeters.	Baseline, 1 month, 3 months, and 6 months postoperatively.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Probing Depth (PD)	Change in probing depth measured in millimeters.	Baseline, 1 month, 3 months, and 6 months postoperatively.
Clinical Attachment Level (CAL)	Change in clinical attachment level measured in millimeters.	Baseline, 1 month, 3 months, and 6 months postoperatively.
Oedema Score in the Recipient Site	Oedema was scored clinically in the recipient area using a 0-4 ordinal scale (0 = none; 1 = mild, intraoral oedema limited to the surgical site; 2 = moderate, extraoral oedema limited to the surgical site; 3 = significant, extraoral oedema extending beyond the surgical site; 4 = severe, extraoral oedema extending beyond the surgical site with limited mouth opening). Examinations were performed by a calibrated and blinded examiner. Higher scores indicate more severe oedema. Unit of Measure: Units on a scale (0-4)	Postoperative days 3, 5, 7, 14, 21, and 28.
Erythema Score in the Recipient Site	Erythema was scored clinically in the recipient area using a 0-4 ordinal scale (0 = none, tissues fully pink; 1 = mild, <25% of tissues red; 2 = moderate, 25-50% of tissues red; 3 = significant, 50-75% of tissues red; 4 = severe, >75% of tissues red). Examinations were performed by a calibrated and blinded examiner. Higher scores indicate greater severity of erythema.	Postoperative days 3, 5, 7, 14, 21, and 28.
Pain Intensity (VAS Score)	Postoperative pain intensity was assessed using a 0-10 Visual Analog Scale (VAS), where 0 = no pain and 10 = maximum tolerable pain. Patients recorded their pain level daily during the first postoperative week. Higher scores indicate greater pain intensity.	First postoperative week.
Analgesic Consumption	The number of analgesic tablets taken during the first postoperative week was recorded by each patient on a provided daily log form. Higher values indicate greater postoperative analgesic use.	First postoperative week.

Collaborators and Investigators

• Sponsor: Kahramanmaras Sutcu Imam University
• Investigators: Principal Investigator: esra bozkurt, Kahramanmaraş Sütçü İmam University

Publications and helpful links

General Publications

• Shakiliyeva S, Sahin D, Gunpinar S, Gursel M. Comparison of conventional and modified sling suture techniques in free gingival graft operations-a randomized controlled clinical trial. BMC Oral Health. 2025 Feb 21;25(1):279. doi: 10.1186/s12903-025-05456-x.

Helpful Links

• Inonu University Clinical Research Ethics Committee

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2024
• Primary Completion (Actual): August 30, 2025
• Study Completion (Actual): August 30, 2025

Study Registration Dates

• First Submitted: December 11, 2025
• First Submitted That Met QC Criteria: December 11, 2025
• First Posted (Actual): December 24, 2025

Study Record Updates

• Last Update Posted (Actual): December 24, 2025
• Last Update Submitted That Met QC Criteria: December 11, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: low-level laser therapy; free gingival graft; injectable platelet-rich fibrin; shrinkage
• Additional Relevant MeSH Terms: Periodontal Atrophy; Periodontal Diseases; Mouth Diseases; Stomatognathic Diseases; Gingival Diseases; Gingival Recession; Therapeutics; Laser Therapy; Phototherapy; Low-Level Light Therapy; proliferation regulatory factors, human urine
• Other Study ID Numbers: 2024/84

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared to ensure patient privacy and confidentiality.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No