All ETDs from UAB

Advisory Committee Chair

Chung How Kau

Advisory Committee Members

Maria L Geisinger

Terpsithea Christou

Yedeh Ying

Document Type


Date of Award


Degree Name by School

Master of Science (MS) School of Dentistry


Smiling is the most useful way people can use to express their emotions, therefore, it is critical to build our treatment plan not just around establishing a stable functional occlusion but also to achieve beautiful harmonious smile. It has been suggested that the smile may be made up of 3 components: Gingival component, soft tissue component, and dental component, and the ultimate smile beauty can be achieved by trying to find the balance in between these components. We collected 68 smiling photos for cases were taken to American board of orthodontics clinical exam and they were considered successfully treated, all photos were cropped using a standardized template of 16*9, and were graded by a panel of 52 person from different specialties. Simple descriptive statistics were used to determine the mean, standard deviations and quartiles of the smile attractiveness. And multi-linear regression (MLR) analysis was used to examine the relationship of smile attractiveness when the variables of age, professional experience, gender of the raters were considered. In addition, the MLR analysis was also used to determine if the gingiva, lips, teeth played a role in the final smile attractiveness outcomes. and Receiver operating characteristic ROC was created to correlate the association between smile attractiveness and the perfect smile. All the statistical analyses were conducted using SAS 9.4 (Cary, NC). The mean rating of each picture ranged from 3.42 ± 1.83 (least attractive smile) to 8.46 ± 1.59 (most attractive smile). The overall mean for smile attractiveness was 6.23 ± 1.09, additionally, it was found that problematic teeth, gingiva, and lips reduces the smile attractiveness score by 1.7, 1.7, and 1.2 respectively. Likewise, we found that just 2 out of 68 or 2.94% of the cases have perfect smile. In conclusion, 2 out of 68 American Board of Orthodontics treatment finishes had an attractive and perfect smile, furthermore, the smile attractiveness seems to be affected mostly by the teeth, and finally, responders age, occupation, and gender doesn’t tend to influence the smile attractiveness rating.

Included in

Dentistry Commons



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