Abstract
Statement of problem
Dentists strive to create natural looking teeth for their patients. However, much
of the research on esthetic dentistry has used artificial and computer-generated images
to establish esthetic norms. Altered images are helpful in determining personal preferences
but may be misleading for natural norms.
Purpose
The purpose of this report from the Committee on Research in Fixed Prosthodontics
of the American Academy of Fixed Prosthodontics was to establish an evidence base
for clinical guidelines on lip mobility and the visibility of oral tissues.
Material and methods
A systematic search was conducted to collect data on the lip border movements and
the visibility of teeth and gingiva of human participants.
Results
One thousand and ninety-six articles were processed, and, based on inclusion criteria,
48 articles were reviewed. The findings determined that the upper lip lengthens with
age resulting, at rest, in less display of the maxillary teeth and more of the mandibular
arch. When evaluating the maxillary incisal edge position at rest, the canines are
the most reproducible. Women tend to display more gingiva in a social smile than men,
but this may not be so for a true smile of joy. Both the middle and lower facial thirds
should be evaluated to detect a maximal smile. Care must be taken not to classify
a person incorrectly as having a low smile line because they could still have a potential
to show gingiva.
Conclusions
Evidence-based clinical guidelines are offered to reduce the risk of esthetic failures.
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Article info
Publication history
Published online: May 21, 2021
Identification
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© 2021 by the Editorial Council for the Journal of Prosthetic Dentistry.
