Comparison Between Lip Repositioning and Muscle Traction Technique in Treatment of Gummy Smile

Controlled Randomized Clinical Trial of Containment of the Elevator Muscle of Upper Lip and Wing of Nose Technique Versus Conventional Lip Repositioning for Treatment of Gummy Smile

The goal of this clinical trial is to compare and evaluate the effectiveness of conventional and modified lip repositioning for the treatment of gummy smile.

The main question it aims to answer:

Which of these treatment modalities (conventional lip repositioning and containment of the elevator muscle of the upper lip and wing of nose (EMULWN)) has the most durable and least relapse in the treatment of gummy smile?"

Researchers will compare:

1. The primary outcome was the decrease in excessive gingival display by measuring smile line (gingival display) and smile index before and after treatment modalities.
2. The The secondary outcome was to measure the durability and possibility of relapse over 6 months after treatment with high patient satisfaction.

Study Overview

• Status: Completed
• Conditions: Gummy Smile Due to Hypermobile Upper Lip; Excessive Gingival Display
• Intervention / Treatment: Procedure: lip repositioning; Procedure: Containment of the elevator muscle of the upper lip and wing of nose (EMULWN) technique

Detailed Description

For patients seeking long-term correction of excessive gingival displays, there are different treatment modalities. Both lip repositioning and muscle traction techniques showed improvement in the decrease in the amount of gingival display, while the containment surgery of the muscle of the upper lip and wing of the nose showed durable and satisfactory esthetics with less patient discomfort and less pain immediately after the procedure and needs more time to study or may need some modification. Also, lip repositioning showed satisfactory results to the patients but with more pain immediately after the procedure.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Egypt
  • Egypt
    • Cairo, Egypt, Egypt, 1234
      • Periodontology Clinic in Suez Canal University
  • Ismailia Governorate
    • Ismailia, Ismailia Governorate, Egypt, 1234
      • Periodontology Clinic in Suez Canal University

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Adult patients aged between 18 and 38 years.
2. Gummy smile ranging between 4 and 6 mm, due to short upper lip and hyperactive lip elevator muscles (lip mobility >8 mm).
3. Good periodontal health based on the examination of the gingival inflammation index, bleeding index, and probing the depth of gingival pockets.
4. Healthy patients or people with well-controlled systemic disease.

Exclusion Criteria:

1. Smokers.
2. Pregnant or lactating women.
3. Less than 3 mm of attached gingiva that might create difficulties in flap design, stabilization, and suturing.
4. Vertical maxillary excess of more than 6 mm.
5. Poorly controlled systemic diseases that preclude local anesthesia.
6. Altered passive eruption, which needs gingivectomy or an apically positioned flap.
7. Skeletal causes of gummy smile as protruded maxilla.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: lip repositioning; lip repositioning to treat excessive gingival display	Procedure: lip repositioning; Local anesthesia was administered in the vestibular mucosa. A partial-thickness incision was made at the mucogingival junction from the mesial line angle of the right first molar to the mesial line angle of the left first molar. A second partial- thickness incision, parallel to the first, was made in the labial mucosa, 10 to 12 mm apical to the mucogingival junction. The incisions were connected at each first molar, creating an elliptical outline. The epithelium was removed within the outline of the incisions, leaving the underlying connective tissue exposed. Care was taken to avoid damage to any minor salivary glands in the submucosa. The parallel incision lines were approximated with interrupted stabilization sutures at the midline and other locations along the borders of the incision to ensure proper alignment of the lip midline with the midline of the teeth. Then, a continuous interlocking suture was used to approximate both flap ends.
Active Comparator: Containment of the elevator muscle of the upper lip and wing of nose (EMULWN); Containment of the elevator muscle of the upper lip and wing of nose (EMULWN) technique in treatment of excessive gingival display	Procedure: Containment of the elevator muscle of the upper lip and wing of nose (EMULWN) technique; Local anesthesia was administered in the vestibular mucosa and lip then a vertical incision was made on the labial frenum, and two more horizontal incisions were made on the mucogingival line, starting from the frenum incision up to the height of the canines. The flap was carefully divulsed with Goldman Fox scissors and also a curved hemostat, separating the external epithelium from the muscle bundle mucosa on both sides at the height of the lateral incisors and canines. With an absorbable suture thread, the elevator muscle of the upper lip and wing of the nose was pulled downwards, repositioning its bundle nearer the highest portion of the keratinized gingiva. Simple sutures were made, as many as necessary, in order to contain the pulled muscle in this position. The procedure ended up with a continuous suture in the labial frenum and in the horizontal incisions with the use of a 4-0 silk suture thread. The external stitches should be removed in 10-15 days" time.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Measuring smile line (the amount of gingival display in millimeters)	The first primary outcome of the study was to measure the change in excessive gingival display by measuring smile line (the amount of gingival display in millimeters) before and after treatment. 1/Smile line (gingival display) Type 1: Very high smile line: 2 mm or more of marginal and attached gingiva visible or more than 2 mm of root or gingiva apical to the cemento-enamel junction visible for the healthy but reduced periodontium. This smile is classified as a "gummy smile." Type 2: High smile line: Between 0 and 2 mm of marginal and attached gingiva visible or between 0 and 2 mm visibility of root and gingiva apical to the cemento-enamel junction visible for the reduced and healthy periodontium. Type 3: Average smile line: Gingival embrasures only visible. Type 4: Low smile line: Gingival embrasure and cemento-enamel junction not visible.	at baseline, after one month, after 3 months and after 6 months
Measuring smile index ratio before and after treatment.	The second primary outcome of the study was to measure the change in excessive gingival display by measuring smile index ratio which is (intercommissural width/interlabial gap) to visualize and quantify the frontal smile. The ratio is used for comparing smiles among patients. The lower the smile index, the less youthful the smile appears.	at baseline, after one month, after 3 months and after 6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Patient Satisfaction with Their Smile	Patient satisfaction with their smile was recorded on the following scale: 0 (very satisfied); 1 (satisfied); 2 (moderately satisfied); 3 (unsatisfied).	at baseline, one month, 3 months and 6 months
Patient discomfort	Patient discomfort was recorded on a visual analog scale, with scores from 0 to 10, where 0 corresponds to no discomfort and 10 corresponds to maximum discomfort.	immediately after treatment

Collaborators and Investigators

• Sponsor: Suez Canal University
• Investigators: Principal Investigator: Hany Kamel Shalaby, professor, Suez Canal University

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2023
• Primary Completion (Actual): January 1, 2025
• Study Completion (Actual): March 1, 2025

Study Registration Dates

• First Submitted: September 22, 2025
• First Submitted That Met QC Criteria: December 2, 2025
• First Posted (Actual): December 16, 2025

Study Record Updates

• Last Update Posted (Actual): December 16, 2025
• Last Update Submitted That Met QC Criteria: December 2, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Keywords: Patient Satisfaction; muscle traction; Gummy Smile; Patient Discomfort; Gingival Display; Smile Line; Smile index; lip repositioning
• Additional Relevant MeSH Terms: Behavior; Treatment Adherence and Compliance; Health Behavior; Patient Satisfaction; Investigative Techniques; Methods
• Other Study ID Numbers: 240/2019 suez canal university

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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