EMG-guided Botox Injection Versus Conventional Botox Injection in Gummy Smile Patients

EMG-guided Botox Injection Versus Conventional Injection in Yonsei Point in Gummy Smile Patients: A Randomized Clinical Trial

The goal of this clinical trial is to compare the effect of EMG-guided Botox injection with conventional Botox injection in Yonsei point, in patients with excessive gingival display.

The main question it aims to answer is:

• Does the use of electromyography (EMG) as a guide during Botox injection for patients with gummy smile has better effect than conventional injection in Yonsei point?

Participants will be randomized in equal proportions between intervention and control groups.

• Preoperative assessment of amount of gingival display, lip length (philtrum and vermilion length), and smile type.
• For the intervention group, EMG readings will be done in Clinical Neurophysiology Department, Kasr Al-Ainy Hospital EMG-guided Botox injection (Intervention group). Conventional Botox injection in Yonsei point (Control group).

Inclusion Criteria:

• Patients with excessive gingival display.
• Patients with esthetic concerns.
• Patients with mild to moderate VME (vertical maxillary excess).
• Normal clinical crown dimensions.
• Patients aged 18 to 50.
• Systemically healthy patients.
• Non-smokers.

Exclusion Criteria:

• Patients with severe VME (vertical maxillary excess).
• Pregnant and breastfeeding women.
• Patients with gingival inflammation and/or enlargement.
• Inflammation or infection at the site of injection.
• Patients with known allergy to any of the components of Botox (i.e., saline, human albumin, lactose and sodium succinate).
• Patients using anticholinesterase or other agents affecting neuromuscular transmission.
• Psychologically unstable patients or those who have unrealistic expectations and questionable motives.
• Patients with neuromuscular disorders (e.g., myasthenia gravis, Eaton-Lambert syndrome).