NCT03717987

The Effect of Botulinum Toxin A In Patients With Excessive Gingival Display With And Without Zinc Supplementation

Completed Phase 3 Last updated 20 May 2022

What this trial tests

Phase 3 trial testing Botulinum toxin type A in Excessive Gingival Display in 26 participants. Completed in 12 December 2019.

Timeline

3 January 2019

Primary endpoint
1 September 2019

12 December 2019

Quick facts

Lead sponsor	Cairo University
Phase	Phase 3
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	double
Primary purpose	treatment
Enrollment	26
Start date	3 January 2019
Primary completion	1 September 2019
Estimated completion	12 December 2019
Sites	1 location across Egypt

Drugs / interventions tested

• Botulinum toxin type A (BOTULINUM TOXIN TYPE A) — full drug profile →
• Zinc supplementation — full drug profile →

Conditions studied

• Excessive Gingival Display — all drugs for Excessive Gingival Display →

Sponsor

Cairo University

Who can join

Adults 18 to 50, any sex, with Excessive Gingival Display. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

It has been noted since the start of using botulinum toxin for both medical and cosmetic indications that some patients simply don't achieve the responses to the drug that others do, leading to increased dose requirements and more frequent treatments. It was from this observation that researchers started to look at the zinc levels of patients and consider the concept of supplementation. In a recent systematic review, it was reported that there is very scant evidence to determine the exact clinical effects and duration of BTX-A when injected to treat gummy smile patients. Therefore, the investigators want to administrate of zinc supplements to patients prior to BTX-A injection to study if it will enhance its clinical effects, since it is from the zinc dependent metalloprotease family, where for each botulinum toxin molecule to be effective in paralyzing a muscle response it must be associated with a molecule of zinc which could be found within the cells of the body.

Participants with esthetic concern of excessive gingival display who meets the inclusion criteria will be assigned randomly and blindly to one of the 2 groups. Patients in the intervention group will take zinc supplement tablets to increase zinc levels for 4 days before botulinum toxin injections. While patients in the control group will take placebo tablets 4 days prior to the injections. All tablets will be placed in envelopes for blinding the operator, and numbered by a supervisor to allocate patients again in their groups for statistical results. Botulinum toxin type A will be injected in all patients at both sides into the "Yonsei point," (3Units) the point that would target 3 muscles responsible for upper lip elevation during smiling, including the LLSAN, in a single injection. This landmark was identified as the center of a triangle formed by the convergence of the LLSAN, the LLS, and the Zminor muscles and is located 1 cm lateral to the ala horizontally and 3 cm above the lip line vertically in both men and women. After 2 weeks the patients would come for an additional touch up dose (1 unit at each injection point).

Publications & conference data

1 peer-reviewed publication reference this trial (live from Europe PMC):

1. Botulinum Toxin Type A and Hyaluronic Acid Dermal Fillers in Dentistry: A Systematic Review of Clinical Application and Indications.
   Maci M, Fanelli C, Lorusso M, Ferrara D, et al · · 2024 · cited 2× · PMID 39027812 · DOI 10.14740/jocmr5202