Phi is found in the dimensions of the teeth, mouth, lips and even your smile.
For several decades, Dr. Eddy Levin of the U.K. has used the concept of phi to design aesthetically pleasing cosmetic and orthodontic corrections in the field of dentistry. Dr. Levin’s principles are compulsory study in many American Dental Schools.
The images below show several how phi proportions appear in the mouth, lips and nose.
These proportions can be determined by using Dr. Levin’s steel Golden Mean gauges and plastic grids or, for digital photo applications, with Dr. Levin’s Phi Dental Grid software. Click on the links below for more information.
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| Golden Mean Gauge | Dental Grids |
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| Dr. Levin’s Phi Dental Grid Software | |
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| Midline:Arch Corner: Smile edge proportion | Chin:Tooth Edge: Nose proportion |
In a perfect smile, the front two incisor teeth form a golden rectangle, with a phi ratio in the height to the width. The ratio of the width of the first tooth to the second tooth from the center is also phi. The ratio of the width of the smile to the third tooth from the center is phi as well.
The grid above is for a central tooth with a width of 8.5mm.
Visit the site of Dr. Eddy Levin for more on the Golden Section and Dentistry.