Smile Evaluation

Facial analysis for smile evaluation

  1. Facial midline and midline of centrals
  2. Inter-pupillary lines to incisal edge
  3. Full face analysis
facial analysis smile evaluation

Sagittal plane analysis

  1. Ricketts E-Plane (4mm from upper lip and 2mm from lower lip)
  2. Nasio-labial angle M=90-95 degree F=100-105 degree (can determine cervical thickness crowns or veneers if lip covers in smiling)


Smile evaluation and Dental analysis

Step #1 = Incisal edge and embrasures

  • Amount of tooth showing at rest (use M sound to determine)
  • Phonetically the F and V sound should but edge at wet/dry (vermillion) border of lower lip
  • Curvature follows lower lip
  • RULE of 42.2 4mm central show at rest and within 2mm lower lip  2mm most gingiva show at smile
  • Lips at rest canine is at “0” display
  • Fills 50-60% of distance from upper to lower lip @ rest

Incisal embrasures and height of contacts

Step #2 = Midline symmetry

  • Kokich shows up to 4mm and layperson does not notice

Step #3 = Gingival margin

Step #4 = Mirror the centrals and cousin the rest

Step #5 = Golden Proportion

golden proportion smile evaluation
  • Centrals = 50% Laterals = 30% and viewable portion from facial of Canines = 20%
  • Width is 78% length 75-80 range
  • 10.5mm is about average length central incisor and good starting point

Step #6 = Angles of teeth

  • All teeth incline towards belly button
  • Fill the buccal corridor
smile evaluation


Step #7 = Hue, Chroma, Value and incisal translucnecy of teeth

Step #8 = Shape and texture of teeth

Papilla height as compared to contact length. Ideally the papilla tip should take up 45-50% of the total length of the tooth from the gingiva to the end of the contact, with the contact using up the remaining 50-55% of this distance. Tapered incisors are preferred for men and women. Del Monte 2017 JPD

Step #9 = Protrusive or retrusive

  • Want a reflective surface
  • Deflective surface is common with post ortho upper bi-ext
  • Deflective teeth look smaller and DARKER
smile evaluation
Deflective on left and composite added to facial to make right side reflective


Line angles of anterior teeth

Central incisor line angles

The lateral has one distinction in it’s line angles.

Lateral incisor line angles

The reflective surface, also known as the facial plane, is the area within the line angles.


Iamge of reflective area central incisorLine angles of anterior teeth


How to fix the esthetics of an anterior tooth.