Pacific Coast Society of Orthodontists Bulletin Spring 2015 - (Page 30)

SUMMARY ANNUAL SESSION SMILE AND APPLIANCE ESTHETICS - NEW UNDERSTANDINGS Presented by Dr. Henry Fields, PCSO Annual Session, October 4, 2014. Summarized by Dr. Bruce P. Hawley, PCSO Bulletin Northern Region Editor. D oes facial attractiveness have any true social or tangible value? Attractive individuals appear to have greater interpersonal success in the workplace, in school, and in social situations. The relative attractiveness of an individual influences how people perceive a particular dental feature, such as a missing incisor or a cleft. Dentists and orthodontists tend to rate tooth positions as the most important variable; laypersons might regard hairstyle as most important, with perhaps only around 25% of overall attractiveness related to dental esthetics. Dr. Fields VARIABLES TO SMILE ESTHETICS FOR LAYPERSONS A number of morphologic elements may play a part in the esthetics of a smile. These may include the buccal corridors, smile arc, gingival height of maxillary central and lateral incisors, overall maxillary gingival display, incisal edge discrepancy between upper centrals and laterals, overbite, gingival margin discrepancy between maxillary central incisors, upper dental midline to facial midline, difference between maxillary and mandibular dental midline positions, and occlusal plane cant. Laypersons do notice buccal corridors, but it is an unreliable measure for esthetics. With respect to the smile arc, people like incisal edges that track the lower lip. Although the most prevalent opinion is that laypersons prefer some lip coverage of the cervical area of the tooth, a large range of gingival display is acceptable; if you have to err in treatment, leaving a little extra gingival display is suggested because lips tend to thin and sag as we age. Laypeople accept up to 3 mm deviation of the maxillary dental midline with respect to the facial midline, and 2 to 3 mm of occlusal cant is within the acceptable range. Up to 2.5 mm difference in the positions of maxillary and mandibular dental midlines are accepted, and the removal of a mandibular incisor during orthodontic treatment does not create an issue. In terms of overbite, 2 mm is esthetically ideal, but you can go up to 5 mm and still be in the acceptable range. Gingival level differences between 30 maxillary central incisors are tolerable up to around 2 mm; between maxillary central and lateral incisors the ideal difference is 0.5 mm, with up to 2 mm difference being acceptable. Incisal edge location differences of maxillary central and lateral incisors are ideally 1 mm, with up to 2 mm accepted. So there is a large range of acceptability of smile variables by the lay public. In comparing full face vs. lower-face-only views, only two variables, gingival display and occlusal cant, show different lay responses. The relative attractiveness of a patient makes a difference for all variables except occlusal cant. Smile variables without facial context are not affected by facial attractiveness or the sex of the model, and they can be evaluated at any visual perspective. Smile variables with facial context (buccal corridor, smile arc, maximum gingival display, and maxillary dental midline to the face) are affected by facial attractiveness and the sex of the model (these are evaluated at a two-foot speaking distance). Keep in mind that the methods drive the raters to the oral areas and structures in the absence of the full facial context, and that young adult models are used here. VISUAL PREFERENCES When unprompted, where do people look while viewing the face? Do they look at the circumoral area? Is attention given dependent on background facial attractiveness or on the level of malocclusion? Findings show that the human eye tracks for 80 milliseconds before fixating. (Here, the subjects and images are all young adult Caucasian females.) In attempting to measure this objectively, it is difficult to determine where the first eye fixation takes place. Instead, noting where people look the most, and for the longest duration, is more reliable. Bad-looking teeth are found to be a greater detriment to an attractive person than to a less attractive individual. Females look at the eyes more; males look at the eyes less (but still more than other areas). Males tend to look more at the mouth and PCSO BULLETIN * SPRING 2015

Table of Contents for the Digital Edition of Pacific Coast Society of Orthodontists Bulletin Spring 2015

The Whole is Greater Than Its Parts
The Land of Opportunity
Donated Orthodontic Services Program — AAO-DOS
Trustee Report
AAO Council on Scientific Affairs (COSA) Report
Component Reports
AAOF Report
AAO Leaders Complete Terms in San Francisco: The End of an Era for PCSO
Preparing for the Unexpected: Your Emotional SOS Plan Part I
Resident Spotlight: Dr. Mona Afrand, Orthodontic Resident, University of Alberta Department of Orthodontics; Younger Member Spotlight: Dr. Mostafa Altalibi, Calgary, Canada
PCSO At A Glance
The AEODO Research Data Portal: Restructuring Workflow
The Aveolar Bone Housing — The Orthodontist’s World
Case Report Pre-Treatment
Smile and Appliance Esthetics — New Understandings
How to Remember Names and Places: A Dale Carnegie Program
The Latest Trends in Orthodontic Treatment: Part I
Training and Giving Feedback to The Clinical Staff to Ensure a Well-Tuned Team
Treatment Possibilities with Invisalign®
Class III Treatment: Timing and Protocol
Orthodontics: The Key to Successful Interdisciplinary Treatment
CBCT: Assessment of Anatomical Boundary Conditions Important to Orthodontists
Case Report Post-Treatment
Sectional Mechanics for Class II Correction
Dr. Donald Poulton

Pacific Coast Society of Orthodontists Bulletin Spring 2015