For beautiful smile, the center line of a nose and upper front teeth must be aligned. If their center lines are not aligned to each other, the condition of oral structure must be check out if there is any malocclusion as it or one sided biting habit can lead to facial asymmetry. Long term loss of a natural tooth also triggers deterioration of alveolar bone causing imbalance of facial structure, thus, it is critical to maintain healthy oral structure through appropriate treatment such as orthodontics or dental implants.
Golden-Ratio of a Smile Line
1. Center line alignment of a face and teeth
2. Visibility of upper anterior teeth (4 on each side, 8 in total) 
3. Lip ends should not be tilted up or down. 
4. Prominent canine teeth must be symmetrical. 
5. Upper lip should be between upper gums and teeth when smiling.
Most Natural Gum Line Design
The gum line exposed too much or too less between your lips often gives out unnatural impression. If your gum line is too low or too high, laser gingivoplasty can help you achieve beautiful smile without bleeding. For darker or dull gum color, gum peeling or bleaching procedures are used to restore the color of bright pinkish-red gums.