Edge design: the line your lower lip should follow
The biting edges of the upper teeth should form a gentle curve that follows the lower lip, and a perfectly flat, straight edge line is a classic giveaway.
When you smile, the line made by the tips of your upper front teeth is one of the first things people see. In a youthful, natural smile, that line curves gently upward at the sides, following the lower lip. Flatten it into a ruler-straight edge and the smile can look older, artificial or both.
What edge design includes
Dentists call the curve of the upper edges the smile arc. Smile-design literature describes the ideal as consonant, meaning the curve of the upper incisal edges runs roughly parallel to the inner curve of the lower lip in a posed smile. A flat smile arc is one where the edges run straighter than the lip. The arc also tends to flatten naturally with age and wear.
Edge design is also about the small details. The two central incisors are usually slightly longer than the laterals. The small V-shaped gaps between tooth tips, called incisal embrasures, are typically narrow at the center and open a little more toward the sides. Edges that are too long or poorly planned can also be more likely to chip if they clash with the bite.
Excellent work vs. the giveaway
- Excellent: the edge line curves gently with the lower lip.
- Excellent: centrals sit a touch longer than laterals, with small, natural embrasures between tips.
- Giveaway: a perfectly straight line across all the upper teeth, like a cut hedge.
- Giveaway: no embrasures at all, so the teeth look fused into one block.
- Giveaway: edges that tilt, with one side visibly longer than the other.
How to check it yourself
- Take a straight-on photo of a full, natural smile with the camera level with your mouth. Trace the tips of the upper teeth with your eye and compare with the lower lip.
- Look at the tips of the front teeth. Can you see small notches between them, or one continuous edge?
- Check symmetry. Draw an imaginary line across the edges. Does it slope to one side?
- Say a few words in the mirror. Edges that are too long may touch the lower lip or affect certain sounds.
Edge position affects looks, speech and bite at the same time, so it is planned in the mouth, not only on a screen. At a consultation, ask whether you can try the planned edge position in a temporary mock-up, and how the dentist will check it against your bite. Your own lip line and bite decide what is right for you.
Sources
Educational content, not individual medical advice. Every mouth is different, so talk to a licensed dentist about your own teeth. The Real Miami Dentists is powered by 5 Star Smiles.
