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

University of Medicine and Pharmacy at Ho Chi Minh City

Status and phase: Completed; Phase 4

Conditions: Gummy Smile

Treatments: Procedure: Clinical crown lengthening surgery

Study type: Interventional

Funder types: Other

Identifiers

NCT05057286

20338-DHYD

Details and patient eligibility

About

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.

Enrollment: 20 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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20 participants in 1 patient group

Subjects with gummy smile

Experimental group

Description:

The study procedure consisted of recruitment, pre\&post-operative photography, gingivoplasty, BTX-A injection, recall visits, and data collecting.

Treatment:

Procedure: Clinical crown lengthening surgery