J Am Acad Dermatol. 2010 Dec;63(6):1042-51. doi: 10.1016/j.jaad.2010.02.053.
Gummy smile (GS) is an aesthetic disorder for some patients, which can be corrected by injection of botulinum toxin.
We sought to classify GS according to the area of gingival exposure and the respective muscles involved in order to perfect the botulinum toxin injection technique for each patient.
Sixteen patients with GS were evaluated before receiving botulinum toxin injections. Based on the area of excessive gum displayed and identification of the muscles involved, 4 different types of GS were identified: anterior, posterior, mixed, and asymmetric. AbobotulinumtoxinA (Dysport, Ipsen Biopharm Limited, Wrexham, UK) was injected using a different injection technique for each type of GS, based on the main muscles involved. With the aid of two computer programs, the area of gum exposed was measured before and after the application of abobotulinumtoxinA, to evaluate the level of improvement.
There was a decrease in the degree of gum display in all patients. The general average improvement achieved was 75.09%. Two patients showed slight adverse effects that were easily corrected with additional doses of abobotulinumtoxinA.
For this study, there was no sample size calculation and no statistical analysis of the cases.
The authors conclude that it is important to identify the type of GS and therefore the main muscles involved, so that the correct injection technique can be used. AbobotulinumtoxinA was shown to be effective and safe for use in all types of GS in the present sample.
对于一些患者来说，牙龈外露过多（GS）是一种美学障碍，可以通过注射肉毒毒素来矫正。
我们旨在根据牙龈暴露区域和涉及的相关肌肉对 GS 进行分类，以便为每位患者完善肉毒毒素注射技术。
16 例 GS 患者在接受肉毒毒素注射前接受了评估。根据过度牙龈显露的区域和涉及的肌肉，确定了 4 种不同类型的 GS：前型、后型、混合型和不对称型。根据主要涉及的肌肉，对每种 GS 类型采用不同的注射技术，注射阿 BotulinumtoxinA（Dysport，Ipsen Biopharm Limited，Wrexham，英国）。借助两个计算机程序，在应用阿 BotulinumtoxinA 前后测量暴露的牙龈面积，以评估改善程度。
所有患者的牙龈显露程度均有所下降。总体平均改善程度为 75.09%。两名患者出现轻微不良反应，通过追加阿 BotulinumtoxinA 剂量即可轻易纠正。
对于本研究，没有进行样本量计算，也没有对病例进行统计学分析。
作者认为，重要的是要识别 GS 的类型，从而识别主要涉及的肌肉，以便使用正确的注射技术。在本样本中，阿 BotulinumtoxinA 被证明对所有类型的 GS 均有效且安全。
