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

"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 (Hwang et al. 2009) and (Nasr et al. 2015)."

zinc supplementation will be given to patients in the intervention arm 4 days prior to Botulinum toxin type A injection