Effect of Clinical Crown Lengthening Surgery and Botulinum Toxin A Injection in Gummy Smile Treatment

The Effect of a Combination Between Clinical Crown Lengthening Surgery and Botulinum Toxin A Injection in Gummy Smile Treatment

Background: The demand for beauty is increasing in society as everyone is looking for cosmetic improvement, including gummy smile correction.

Object: This study aims to evaluate the efficacy of a combination of a clinical tooth crowns lengthening surgery following by a BTX-A injection in gummy smile treatment upon based on clinical assessment and photography

Method: An uncontrolled longitudinal study was implemented at the Faculty of Odonto-Stomatology (FOS) of the University of Medicine and Pharmacy at Ho Chi Minh City (UMPH), Viet Nam, from August 2020 to May 2021. Twenty patients (19 females and one male) at a mean age of 24 years old who came for gummy smile chief complaint were included in the study. Subjects were operated to lengthen the clinical crown following an additional botulinum toxin A injection two months post-surgery. All the participants answered the smile esthetic satisfactory questions and were photographed at the time before treatment (T0), two months after clinical crown lengthening surgery (T1), two weeks (T2), and two months (T3) follow-up visits after BTX-A injection. The gingival exposure (GE) and clinical crown length (CCL) were measured at each time point for analysis.

Study Overview

• Status: Completed
• Conditions: Gummy Smile
• Intervention / Treatment: Procedure: Clinical crown lengthening surgery

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Phase 4

Contacts and Locations

Study Locations

• Vietnam
  • Ho Chi Minh City, Vietnam, 749000
    • Faculty of Odontostomatology - University of Medicine and Pharmacy at Ho Chi Minh City

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Gummy smile because of 2 combined etiologies:

  • Short clinical crown of teeth due to the altered passive tooth eruption
  • Hyperactivity of upper lip muscles (lip mobility level > 8mm)

Exclusion Criteria:

• Pregnant or breastfeeding patients

• Gummy smiles due to:

  • Maxillary bone overgrowth (maxillary hypertrophy)
  • Vertical maxillary excess
  • Neuromuscular disorder
  • Gingival hyperplasia due to medicine, supplements, or neuromuscular transmission inhibiting agents
• Systematic diseases that can affect the result of surgical treatment (such as diabetes, heart disease taking blood anticoagulant medicament, blood diseases, immunodeficiency disease etc.)
• Allergy to BTX-A or albumin
• History of taking BTX-A injection in the head-neck area formerly
• Patient with any contraindication of surgery

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Subjects with gummy smile; The study procedure consisted of recruitment, pre&post-operative photography, gingivoplasty, BTX-A injection, recall visits, and data collecting.

Procedure: Clinical crown lengthening surgery; Clinical dental crown lengthening surgery protocol: a clinical crown lengthening surgery was performed.; Post-operation protocol Patients were all prescribed antibiotics , anti-inflammation, analgesic, and an antiseptic mouthwash. Patients were instructed for oral hygiene and recalls.; Botulinum Toxin A injection One hundred units (U) of botulinum toxin A (BTX-A) were diluted with 2.5ml of sterile saline solution without shaking. 1 mm syringe with a 30-gauge needle was used to get 0.25ml BTX-A for four-point injection, or 0.6ml in case injection of 6 points. Cold compress was applied extraoral 5 mins at injection site before injection. After local anesthesia, the doctor administered slowly 2,5 U of diluted BTX-A at each point until white cellulite appeared. Patients were recalled two weeks (T2), and two months (T3) after injection.; Other Names: Botulinum toxin A injection

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Gingival exposure	The outcome is measured in millimeters based on photos of subjects included	At the time before treatment (T0)
Gingival exposure	The outcome is measured in millimeters based on photos of subjects included	Two months after clinical crown lengthening surgery (T1)
Gingival exposure	The outcome is measured in millimeters based on photos of subjects included	Two weeks after Botulinum toxin A injection (T2)
Gingival exposure	The outcome is measured in millimeters based on photos of subjects included	Two months after Botulinum toxin A injection (T2)
Clinical crown length	The clinical crown length is measured in millimeters using digital caliper and periodontal probe	At the time before treatment (T0)
Clinical crown length	The clinical crown length is measured in millimeters using digital caliper and periodontal probe	Two months after clinical crown lengthening surgery (T1)
Clinical crown length	The clinical crown length is measured in millimeters using digital caliper and periodontal probe	Two weeks after Botulinum toxin A injection (T2)
Clinical crown length	The clinical crown length is measured in millimeters using digital caliper and periodontal probe	Two months after Botulinum toxin A injection (T2)

Collaborators and Investigators

• Sponsor: University of Medicine and Pharmacy at Ho Chi Minh City

Study record dates

Study Major Dates

• Study Start (Actual): August 1, 2020
• Primary Completion (Actual): May 31, 2021
• Study Completion (Actual): May 31, 2021

Study Registration Dates

• First Submitted: September 7, 2021
• First Submitted That Met QC Criteria: September 15, 2021
• First Posted (Actual): September 27, 2021

Study Record Updates

• Last Update Posted (Actual): September 27, 2021
• Last Update Submitted That Met QC Criteria: September 15, 2021
• Last Verified: September 1, 2021

More Information

Terms related to this study

• Keywords: Botulinum toxin A; Gingival exposure; Clinical crown length; clinical crown lengthening surgery; Gummy smile
• Additional Relevant MeSH Terms: Physiological Effects of Drugs; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; Cholinergic Agents; Membrane Transport Modulators; Acetylcholine Release Inhibitors; Neuromuscular Agents; Botulinum Toxins; Botulinum Toxins, Type A
• Other Study ID Numbers: 20338-DHYD

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: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: Yes