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Comparison Between Liquid Fibrin and Soft Laser Effects on Healing and Relapse After Lip Repositioning Surgery

Comparison Between The Effect of Liquid Platelet-Rich Fibrin and Low-Level Laser Therapy on Enhancing Healing and Reducing Relapse After Lip Repositioning Surgery

Status
Recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07532161
Enrollment
22
Registered
2026-04-15
Start date
2026-04-20
Completion date
2027-01-31
Last updated
2026-04-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Gummy Smile

Keywords

Excessive gingival display, Gummy smile, Lip Repositioning Surgery, Injectable Platelet-Rich Fibrin (i-PRF), Liquid Platelet-Rich Fibrin, Low-Level Laser Therapy (LLLT), Wound healing, Postoperative relapse, Gingival display reduction, Esthetic dentistry

Brief summary

A gummy smile can negatively affect a patient's self-confidence and satisfaction with their appearance, leading many individuals to seek effective esthetic solutions. The etiology of this condition varies and may include vertical maxillary excess, short upper lip, hyperactive upper lip, gingival enlargement, or altered passive eruption. Lip Repositioning Surgery is one of the minimally invasive esthetic surgical procedures used to reduce the amount of gingival display during smiling. Despite its effectiveness, this surgery may be associated with challenges such as pain, swelling, delayed wound healing, and the possibility of postoperative relapse over time, which could compromise both esthetic and functional outcomes. To overcome these challenges and enhance surgical outcomes, adjunctive techniques have been introduced to promote healing and determine whether enhancing the biological healing process can reduce the rate of relapse after LRS. Among the most prominent of these are Injectable Platelet-Rich Fibrin (i-PRF) and Low-Level Laser Therapy (LLLT).

Interventions

OTHERLiquid Platelet-Rich Fibrin group

A partial thickness elliptical mucogingival incision was made from the mesial of the central incisor to the mesial of the first molar bilaterally with preservation of the frenulum; vertical height set to twice the excessive gingival display (2:1 ratio), lower margin 1 mm coronal to the mucogingival junction. Epithelium elevated to expose connective tissue (preserving minor salivary glands). Periosteal sutures (4-0 Vicryl, 2-3 per side) placed where connective tissue ≥0.5 mm ; incision edges approximated with simple interrupted 4-0 silk sutures. 20 mL blood collected into additive-free plastic tubes and centrifuged at 300 × g for 5 minutes. The Liquid Platelet-Rich Fibrin layer was aspirated and injected immediately after surgery along incision margins and surrounding tissue at 1 mm depth, multiple points 2-3 mm apart (≈0.1 mL per injection) to achieve homogeneous distribution.

OTHERlow-level laser group

A partial thickness elliptical mucogingival incision was made from the mesial of the central incisor to the mesial of the first molar bilaterally with preservation of the frenulum; vertical height set to twice the excessive gingival display (2:1 ratio), lower margin 1 mm coronal to the mucogingival junction. Epithelium elevated to expose connective tissue (preserving minor salivary glands). Periosteal sutures (4-0 Vicryl, 2-3 per side) placed where connective tissue ≥0.5 mm to ; incision edges approximated with simple interrupted 4-0 silk sutures. low-level laser applied to the surgical site (635nm, 200 mW) as part of the post-surgical treatment and at 3,7,10, and 14 days after surgery.

Sponsors

Damascus University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)

Masking description

Randomized comparative clinical trial with blinded outcome assessment. Outcome assessment was performed by an independent examiner who was blinded to the treatment allocation. Clinical photographs and clinical measurements were coded and evaluated without revealing the group assignment. Statistical analysis was performed using coded data to ensure blinding of the data analyst.

Eligibility

Sex/Gender
ALL
Age
18 Years to 50 Years
Healthy volunteers
No

Inclusion criteria

1. Patients of both genders. 2. Patients presenting with a gummy smile in the maxillary anterior region (more than 3 mm) due to upper lip hypermobility. 3. Age 18-50 years. 4. Systemically healthy individuals, classified as ASA physical status I or II according to the American Society of Anesthesiologists (ASA) classification; that is, patients without systemic disease or with mild, well-controlled systemic conditions. 5. Patients with good oral hygiene, defined as an O'Leary Plaque Index ≤ 40%. 6. No previous lip repositioning surgery.

Exclusion criteria

1. Pregnancy and lactation. 2. Individuals with a previous history of receiving facial Botox or filler injections. 3. Systemic diseases or conditions that contraindicate the use of local anesthesia. 4. Any physical condition that impairs the ability to perform proper oral hygiene measures. 5. Patients who are smokers or alcohol consumers. 6. Inability or unwillingness to cooperate. 7. In adequate width of attached gingiva. 8. Vertical maxillary excess (moderate to severe) requiring orthognathic intervention. 9. Short upper lip 10. Gingival display primarily caused by altered passive eruption requiring crown lengthening.

Design outcomes

Primary

MeasureTime frameDescription
Gingival display (mm)Baseline and 1, 3 and 6 months postoperativelyMeasured in millimeters from the lowest point of the upper lip vermilion border to the free gingival margin of the maxillary teeth (from right second premolar to left second premolar) during full smile.
Wound Healing Indexweekly for 4 weeks postoperativelyWound healing will be assessed using the Wound Healing Index (Huang, Neiva, and Wang, 2005). This is a categorical scale with scores ranging from 1 to 3: 1. = poor healing (significant gingival swelling or redness, severe patient discomfort, slough formation with suppuration); 2. = good healing (mild gingival swelling or redness, mild patient discomfort, slough formation without suppuration); 3. = complete healing (no gingival swelling, redness, suppuration, or patient discomfort, and no slough formation). Higher scores indicate better healing outcomes.

Secondary

MeasureTime frameDescription
Postoperative Pain (VAS 0-100)Days 1-7 postoperativelyPostoperative pain assessed using patient self-reported Visual Analogue Scale (VAS, 0-100), where 0 indicates no pain and 100 indicates worst possible pain. Pain will be recorded daily for the first 7 days after surgery.
Postoperative Edema/SwellingDay 3 postoperativelyPostoperative edema/swelling assessed on the third day after surgery using a clinician-reported rating scale: 0 = no visible oedema; 1. = slight oedema (intra- oral swelling in the surgical zone); 2. = moderate oedema (extra- oral swelling in the surgical area); 3. = severe oedema (extra- oral swelling extending the surgical site) and/or visible hematoma and ecchymosis
Esthetic Satisfaction (VAS 0-100)6 months postoperativelyEsthetic satisfaction assessed using patient self-reported Visual Analogue Scale (VAS, 0-100), where 0 indicates completely dissatisfied and 100 indicates completely satisfied. Evaluation will be performed 6 months postoperatively.
Upper Lip External LengthBaseline, 1,3 and 6 months postoperativelyMeasured from the base of the nose to the lower edge of the vermilion border of the upper lip, assessed at both resting and maximum smiling positions
Upper Lip Internal LengthBaseline, 1, 3 and 6 months postoperativelyMeasured at rest and smile to assess the dimensions of the internal upper lip
Intraoperative complicationsDuring surgeryAny complication during the surgery will be recorded for reporting. A score of 0 will be assigned when none of complications are observed, whereas a score of 1 will be assigned if any complication occurs.
Post-operative complicationsFirst week postoperativelyAny complication related to the surgical intervention and healing following the surgical treatment such as infection, or sensory disturbances will be recorded for reporting. A score of 0 will be assigned when none of these complications are observed, whereas a score of 1 will be assigned if any of them occur.

Countries

Syria

Contacts

CONTACTTarek Qasem, DDS MSc PhD
Tarek2.qasem@damascusuniversity.edu.sy+963 933432778
CONTACTWalaa albarry, DDS
walaa9.albarry.@damascusuniversity.edu.sy+963 996766302
STUDY_DIRECTORTarek Qasem, DDS MSc PhD

Faculty of Dentistry, Damascus university, Syria.

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Apr 30, 2026