Van der Geld Pieter, Oosterveld Paul, Kuijpers-Jagtman Anne Marie
Department of Orthodontics and Oral Biology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
Eur J Orthod. 2008 Aug;30(4):366-73. doi: 10.1093/ejo/cjn009. Epub 2008 Jul 16.
The aims of this study were to analyse lip line heights and age effects in an adult male population during spontaneous smiling, speech, and tooth display in the natural rest position and to determine whether lip line height follows a consistent pattern during these different functions. The sample consisted of 122 randomly selected male participants from three age cohorts (20-25 years, 35-40 years, and 50-55 years). Lip line heights were measured with a digital videographic method for smile analysis, which had previously been tested and found reliable. Statistical analysis of the data was carried out using correlation analysis, analysis of variance, and Tukey's post hoc tests. Maxillary lip line heights during spontaneous smiling were generally higher in the premolar area than at the anterior teeth. The aesthetic zone in 75 per cent of the participants included all maxillary teeth up to the first molar. Coherence in lip line heights during spontaneous smiling, speech, and tooth display in the natural rest position was confirmed by significant correlations. In older subjects, maxillary lip line heights decreased significantly in all situations. Lip line heights during spontaneous smiling were reduced by approximately 2 mm. In older participants, the mandibular lip line heights also changed significantly and teeth were displayed less during spontaneous smiling. Mandibular tooth display in the rest position increased significantly. Upper lip length increased significantly by almost 4 mm in older subjects, whereas upper lip elevation did not change significantly. The significant increasing lip coverage of the maxillary teeth indicates that the effects of age should be included in orthodontic treatment planning.
本研究的目的是分析成年男性群体在自然休息位时自发微笑、说话和露齿过程中的唇线高度及年龄影响，并确定在这些不同功能中唇线高度是否遵循一致模式。样本由从三个年龄组（20 - 25岁、35 - 40岁和50 - 55岁）随机选取的122名男性参与者组成。采用数字摄像方法测量唇线高度以进行微笑分析，该方法此前已进行测试并被证明可靠。使用相关分析、方差分析和Tukey事后检验对数据进行统计分析。自发微笑时上颌唇线高度在前磨牙区通常高于前牙区。75%的参与者的美学区域包括所有上颌牙齿直至第一磨牙。自发微笑、说话和自然休息位露齿时唇线高度的一致性通过显著相关性得到证实。在年龄较大的受试者中，所有情况下上颌唇线高度均显著降低。自发微笑时唇线高度降低约2毫米。在年龄较大的参与者中，下颌唇线高度也有显著变化，且自发微笑时牙齿露出较少。休息位时下颌牙齿露出显著增加。年龄较大的受试者上唇长度显著增加近4毫米，而上唇抬高无显著变化。上颌牙齿唇覆盖度的显著增加表明正畸治疗计划应考虑年龄影响。
