Smile Design

Smile Design

Smile Design is a popular method of planning cosmetic dentistry. It uses a set of defined measurements related to the face, lips, and teeth to define a harmonious and aesthetic smile. This approach is not about creating ‘perfect’ teeth. Since we’re all unique, it’s a way of helping us to create a smile that beautifully fits your face. 

One of the best things about smile design, is that it allows us to explore different cosmetic treatment options. It provides a framework to demonstrate what is possible, and a way of showing you what the outcome could look like. It is a fantastic framework to discuss the specific details of treatment, and it is the best way to make sure that we begin any cosmetic treatment with the end in sight. 

There are a number of different areas that we take into consideration when we’re doing smile design. However, not all of them are necessary or relevant for every patient. On this page we have listed the fundamental technical aspects of smile design to give you an overview of the important considerations in planning cosmetic dentistry. 

Note: this page uses specific dental, anatomical, and technical language. We value communication very highly, and we strive to ensure our patients understand the important details of their oral health and any treatment options. If you have any questions, feel free to contact us and we would be more than happy to answer them.

Facial Height Analysis

  • An average face is divisible into thirds between the soft tissue landmarks of forehead, subnasale, menton.
  • The lower third of the face is further divisible into a 1/3 to 2/3 ratio between subnasale and maxillary incisal edge, and maxillary incisal edge and menton. 
  • Values outside these norms can indicate issues with occlusal vertical dimension, or atypical skeletal growth patterns.
  • It’s not always true, but people with long thin faces tend to have longer, more rectangular shaped teeth. 
Facial Height Analysis

Facial Width Analysis

  • An average face is divisible into fifths, between the soft tissue landmarks of the lateral aspect of the face, and the medial and lateral aspect of the eyes.
  • Facial width can be used to determine ideal anterior tooth segment width, by referencing the canine to position to the lateral aspect of the nose, or medial aspect of the iris. 
  • Facial width analysis can also inform the symmetry of posterior tooth display and smile symmetry. 
Facial Width Analysis

Digital Face Bow

  • The digital face bow directly compares facial features to tooth alignment.
  • It compares the facial to dental midline, inter-pupillary line to maxillary incisal edge line, which typically frame the maxillary posterior buccal segment. 
  • These lines can be used to broadly compare dento-facial symmetry and identify problems related to the cant (slope) of the maxillary dentition. 
Digital Face Bow

Dental Midline Comparison

  • The dental midline comparison compares the facial midline to the maxillary and mandibular dental midlines.
  • It can identify positional, or functional midline shifts.
  • While midline coincidence is ideal, midline shifts up to 3-4 mm are often not readily perceived by patients. 
Dental Midline Comparison

Smile Line Analysis

  • The smile line is a curve of best fit drawn to correspond with the buccal cusps of the posterior and incisal edges of the anterior maxillary teeth. 
  • The smile line is ideally symmetrical across the midline, and is slightly positive. 
  • A strongly positive smile line can indicate a narrow maxillary posterior segment or prominent central incisor position. 
  • A negative smile line can indicate anterior tooth structure loss or posterior tooth overeruption. 
Smile Line Analysis

Mesiodistal Width Analysis

  • The mesiodistal width analysis compares the relative proportion width of the maxillary anterior teeth.
  • The template uses The Golden ratio of 1.6 : 1: 0.6. 
  • This template can be used with reference to either the canines to determine the ideal width of the central and lateral incisors, or with reference to the central incisors to determine the ideal width of the lateral incisors and canines.
Mesiodistal Width Analysis

Current Tooth Proportion

  • The current tooth proportion is an analysis of the presenting length and width of the maxillary anterior teeth.
  • The metric is represented as a percentage of width divided by length. It can be used to determine tooth size discrepancy, crowding, or issues with rotation. 
  • Average (relative) maxillary anterior tooth proportions as viewed from the front range between: 

    – Central incisors: 75-85%
    – Lateral incisors: 50-60%
    – Canines: 45-55%
    – Premolars: 30-40%

NOTE: Values ± 5 – 10% can still be considered aesthetic. Relative proportion of the teeth to each other is more important than stand alone actual proportion.

Smile Line Analysis

Ideal Tooth Proportion

  • The ideal tooth proportion is a box of best fit, positioned with reference to the smile line, current incisal edge position, and current gingival position.
  • It serves as a raw indication of whether modifcation to tooth size is necessary for an ideal aesthetic outcome, and can be used to determine whether gingival or incisal length modi cation is required.
  • In most cosmetic cases, the width of the ideal tooth proportion is constrained by the available mesio-distal space.
  • Average (relative) maxillary anterior tooth proportions as viewed from the front range between:

    – Central incisors: 75-85%
    – Lateral incisors: 50-60%
    – Canines: 45-55%
    – Premolars: 30-40%

    NOTE: Values ± 5 – 10% can still be considered aesthetic . Relative proportion of the teeth to each other is more important than stand alone actual proportion.
Ideal Tooth Proportion

Maxillary Tooth Angulation

  • The maxillary tooth angulation is a line of best fit drawn through the long axis of the maxillary teeth.
  • Tooth angulation should be symmetrical across the midline, and will typically show a slight convergence towards the midline.
  • Asymmetry can indicate rotation, proclination, retroclination, or asymmetrical tooth wear.
  • Average maxillary tooth angulations are measured from a horizontal line perpendicular to the midline. Typically the teeth will show a 5 degree convergence towards the chin.
 
Smile Line Analysis

Composite Dental Analysis

  • The composite dental analysis combines the following:

    – Digital Facebow
    – Smile Line 
    – Mesiodistal Width Analysis – Maxillary Tooth Angulation 

  • It is used as a reference to position the ideal tooth outline. 
Composite Dental Analysis

Ideal Tooth Outline

  • The ideal tooth outline is an outline of the proposed ideal tooth position, displayed over the current tooth position.
  • It is used as a reference to identify changes required to gingival position, incisal edge position, and tooth shape.
  • This image is valuable in the creation of a physical waxup and can be used to explain any necessary fundamental tooth shape changes.
Ideal Tooth Outline

* Please note: We have a transparent fee policy. For further information about fees for our preventative care, see our fee schedule.

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