The evaluation of the lips presents a complex problem since it involves observing the mouth from both opposite as well as in
profile and detecting, if possible, its dynamics while selecting the most representative labial mime. In this way, a smile is revealed
as an expression of privileged reference.
In this report, a young man and woman provide two standard testimonies. This allows an assessment of the labial surface
expressed by means of a reference “trapezium”. These observations lead to criteria proposals related to exposure of the mouth,
the upper lip, the bottom lip, teeth and gums when smiling.
In order to transfer these observations to usual orthodontic practice, the proportions displayed are incorporated into the “assessment
of the modelling of cutaneous profile in teleradiography”, as well as a “punctuation of negative factors” where global consideration
relativises the aesthetic assessment of each patient when making a clinical decision.
(Rev Esp Ortod. 2005;35(3):179-187)