Sellen P N, Jagger D C, Harrison A
Department of Oral and Dental Science, Bristol Dental School and Hospital, United Kingdom.
J Prosthet Dent. 1998 Aug;80(2):163-8. doi: 10.1016/s0022-3913(98)70105-2.
Several factors have been suggested as aids for artificial tooth selection. Numerous methods have been devised for the evaluation of reliable esthetic factors in determining artificial tooth form. There is no universally accepted single esthetic factor that can be used reliably to aid artificial tooth selection.
This article describes a new method incorporating a computer program to analyze four esthetic factors: form of the face, arch form, palatal contour, tooth shape, and to determine whether there was correlation between tooth, face, and arch forms and palatal contour.
Impressions were made of the maxillary dentition of 50 dentate undergraduate dental students with irreversible hydrocolloid impression material and casts formed. A standardized photographic procedure was used to record portrait slides of each subject's face and of maxillary dental arches and central incisors made from dental casts. A comprehensive computer program was developed to correlate esthetic factors by superimposition.
Superimposing outline form between face, tooth, and arch showed that for tooth to face form nearly half the comparisons were dissimilar and only 22% corresponded. This is the lowest level of correspondence in this group. Highest correspondence (28%) occurred between arch to face form, followed by arch to tooth form (24%). Arch to tooth showed the lowest level of dissimilarity (32%). For correlation among the four factors across the sample group based on a comparison of classifications in each subject, men tended to dominate tapering classes, whereas women dominated square and ovoid classes.
Correspondence of outline forms through superimposition revealed an insignificant correlation between face, tooth, and arch forms. Although this method applies high technology, it does not improve the accuracy of determining shape and size of teeth in an edentulous patient. The cost and complexity of the method of measurement may also make it impractical for common application.
有几种因素被认为有助于人工牙的选择。已经设计出许多方法来评估确定人工牙形态时可靠的美学因素。目前还没有一个被普遍接受的单一美学因素能够可靠地用于辅助人工牙的选择。
本文介绍一种结合计算机程序的新方法，用于分析四个美学因素：面部形态、牙弓形态、腭部轮廓、牙齿形状，并确定牙齿、面部和牙弓形态与腭部轮廓之间是否存在相关性。
用不可逆水胶体印模材料制取50名有牙本科牙科学生的上颌牙列印模并灌制模型。采用标准化摄影程序记录每个受试者的面部、上颌牙弓以及由模型制作的上颌中切牙的肖像幻灯片。开发了一个综合计算机程序，通过叠加来关联美学因素。
面部、牙齿和牙弓轮廓形态的叠加显示，牙齿与面部形态的比较中，近一半的对比结果不同，只有22%相符。这是该组中相符程度最低的。牙弓与面部形态的相符程度最高（28%），其次是牙弓与牙齿形态（24%）。牙弓与牙齿的差异程度最低（32%）。基于对每个受试者分类的比较，在整个样本组中四个因素的相关性方面，男性在锥形类别中占主导，而女性在方形和卵形类别中占主导。
通过叠加轮廓形态显示，面部、牙齿和牙弓形态之间的相关性不显著。尽管这种方法应用了高科技，但它并没有提高确定无牙患者牙齿形状和大小的准确性。该测量方法的成本和复杂性也可能使其在实际应用中不切实际。
