Division of Periodontology, College of Dentistry, The Ohio State University, Columbus, OH.
J Periodontol. 2019 Mar;90(3):256-262. doi: 10.1002/JPER.18-0468. Epub 2018 Nov 21.
Excessive gingival display (EGD), or a gummy smile (GS), is a mucogingival deformity that can be of concern to patients. The prevalence of GS etiologies, such as altered passive eruption (APE) and hypermobile upper lip (HUL), has not been reported. The aim of this study was to assess the prevalence of APE and HUL in patients seeking to correct their GS, and to determine possible prevalence differences among patients with different gingival display (GD) levels.
During clinical screening of patients interested in participating in a GS treatment study, GD diagnosis, GD level, and presence of APE and/or HUL were determined. Descriptive statistics were calculated for APE, HUL, and GD group prevalence. Fisher's exact test was used to determine difference in frequency of etiologies between GD groups.
Fifty-six patients were clinically screened (27.2 ± 7.2 years old; 85.7% females; 94.6% with GD, 5.4% without GD). Among patients having GD, 75.5% presented with GD≥4 mm and 24.5% with GD<4 mm. Prevalence of etiologies was: 20.8% APE alone, 45.3% HUL alone, and 34% APE and HUL. The prevalence difference between GD≥4 mm and GD<4 mm groups was statistically significant (p<0.0001); for ≥4 mm GD: 5% presented with APE alone, 50% HUL alone, and 45% APE and HUL; for <4 mm GD: 69.2% presented with APE alone and 30.8% HUL alone.
Among patients seeking GS treatment, HUL is the most predominant etiology and it is often present in combination with APE.
过度牙龈显露（EGD）或露龈笑（GS）是一种黏骨膜畸形，可能会引起患者的关注。改变的被动萌出（APE）和上唇活动度过高（HUL）等 GS 病因的患病率尚未报道。本研究旨在评估寻求矫正 GS 的患者中 APE 和 HUL 的患病率，并确定不同牙龈显露（GD）水平患者中可能存在的患病率差异。
在对有兴趣参加 GS 治疗研究的患者进行临床筛查期间，确定了 GD 诊断、GD 水平以及 APE 和/或 HUL 的存在。计算了 APE、HUL 和 GD 组患病率的描述性统计数据。Fisher 确切检验用于确定 GD 组之间病因的频率差异。
对 56 名患者进行了临床筛查（27.2±7.2 岁；85.7%为女性；94.6%有 GD，5.4%没有 GD）。在有 GD 的患者中，75.5%的患者 GD≥4mm，24.5%的患者 GD<4mm。病因的患病率为：单独 APE 占 20.8%，单独 HUL 占 45.3%，APE 和 HUL 同时存在占 34%。GD≥4mm 和 GD<4mm 组之间的患病率差异具有统计学意义（p<0.0001）；对于≥4mm GD：5%的患者单独存在 APE，50%的患者单独存在 HUL，45%的患者同时存在 APE 和 HUL；对于<4mm GD：69.2%的患者单独存在 APE，30.8%的患者单独存在 HUL。
在寻求 GS 治疗的患者中，HUL 是最主要的病因，并且常常与 APE 同时存在。
