The Honest Tooth: The science behind the perfect smile

Monday, January 7, 2019 - 12:30

Smile often, and live longer! Research has indicated that people who are mostly happy and smile a lot live up to ten years longer than most. 

There are many elements that make up the ‘perfect’ smile, some you might already be aware of, such as symmetry and the ideal shape and size of teeth. Cosmetic dentists have an extraordinary checklist of factors to consider when designing your new smile. Here are a few: 


  • Smile symmetry
  • Reflection of light of enamel
  • Shape of teeth
  • Size of teeth
  • Gum levels
  • Angle of teeth
  • Spaces between teeth
  • ‘dark corridors’ at the side of the mouth
  • Lip posture – how much teeth you show when smiling and how much is shown at rest
  • Translucency of enamel 


How do dentists assess how to give you the perfect smile and what are we looking for in a smile?

Smile enhancement can range from simple teeth whitening to a complete smile makeover Smiling influences your emotional state, can lift your mood and even lift the moods of others.

Smiling positively influences your physical health by; increasing endorphin levels,  lowering blood pressure, boosting your immune system, and decreasing stress.

There are three areas of your smile we look at to get the best aesthetic success.


Face Analysis

The first thing we do is analyse your face, this is done by looking at a few factors.


  1. We look at your side profile (your face shape from the side)
  2. The shape of your smile arch (ie. is your smile slanted and not straight)
  3. The midline (middle of your teeth  and whether it is in line with the middle of your face 
  4. The dynamics of your lips (when you smile, how much of your teeth do you show)
  5. The amount of gum you show when you smile 


Front Smile 

The second thing we look at is your anterior or front region of your smile (that is the smile in the front part of your mouth).

This is done by:


  1. Horizontal position of the edges of your front teeth, that is: are your teeth too far forward, too far back, too long, too short)
  2. Vertical position of teeth, that is: is your smile line following the lip line, touching your lips or reverse. Also how much of your teeth is revealed when you are not smiling.
  3. Width to length ratio of your teeth. Generally the ratio is 80%
  4. The height of your gums  in relation to the ones on the adjacent teeth)
  5. The shape of your teeth and therefore the shape of the space between your teeth called the embrasure.
  6. The inclination of your teeth (are they straight or slanted and if slanted how much are they slanted)


Posterior Smile


The last thing we look at is your posterior smile, that is the way the smile blends with your back teeth.


  1. Is there a space between your cheeks and teeth (buccal corridor)
  2. The way your gums blend in with the back teeth.


Digital Smile Design in Dentistry

Advances in digital dentistry allows us to use  software in which your smile can be designed to suit your face shape. The main advantage is that  patients can visualise a simulation of their cosmetic smile makeover before it even starts.


How does it work?

During your record taking, a series of photos of your teeth and your face are taken which are then uploaded into a Smile Designer  software, The dentist will then design the ideal teeth shape, size, and colour that will best go with your face. Once the design phase is complete you can decide if you want to proceed with treatment .




Dr Shenilee Hazell