What makes a perfect smile?

Results from a University of Minnesota study shows what contributes to a “perfect” smile.

The study called Dynamic properties of successful smiles, was initially published in the  PLOS ONE journal in June.

Researchers surveyed over 800 participants to rate several computer-generated smiles, each with different variations. These smiles differed in mouth angle, wideness, amount of teeth displayed, and symmetry.

(c) Rudi Booker

Each of these factors were correlated with a certain trait, such as fakeness or genuineness, creepy or pleasant, angry, sad, happy, suprirsed, or disgusted. The smile most people found to be genuine were those with a medium angle — not too wide nor too little.

(c) Tu Biganya

Smiles which showed more teeth were judged to be less trustworthy.

(c) Pinterest

The research team says that while symmetric smiles are considered more beautiful and traditionally more aesthetic, slightly crooked smiles were actually favored by the respondents. This plays into the principles of smile design, where dynamic symmetry — being similar but not entirely identical — creates a much more dynamic and genuine smile.

Applications for the research may extend to facial reanimation surgery, rehabilitation of those who suffered from trauma, or neurological cases, which might have hindered their ability to express emotions through their face.