What is assessed?
Teeth, gums and lips together, including movement.
← All explanationsSmile line
Why do people show different amounts of gum when smiling?
In dental aesthetic assessment, smile line often refers to the height of the upper lip during smiling, which helps determine how much of the upper teeth and gums is visible. It differs from the smile arc along the incisal edges. Both describe features of a smile and are not diseases in themselves.
For training & practice ↓
AI-generated
Choose a view
The lip forms the frame
Lip movement exposes different amounts of tooth crown and gum. A gentle smile and a broad laugh may look different.
Arc and height are different
The smile arc describes the curve of the upper incisal edges relative to the lower lip. Smile line here describes the visible height of teeth and gums.
Individual, not a template
Wishes, natural proportions, dental health and function belong together. A photograph or supposed ideal measurement does not establish a need for treatment.
At a glance
Is one measurement right for everyone?
No. An isolated norm cannot replace individual assessment.
When is a discussion useful?
When appearance is a concern or symptoms are also present.
Knowledge in motion
Explained in 36 seconds.
Three steps. No audio.
Each scene can also be selected manually.
Silent educational film with German on-screen text and simplified teaching images. Not a patient case or a promised treatment outcome. The full English explanation is available below.
Read the film text in English
The lip forms the frame
Lip movement exposes different amounts of tooth crown and gum. A gentle smile and a broad laugh may look different.
Arc and height are different
The smile arc describes the curve of the upper incisal edges relative to the lower lip. Smile line here describes the visible height of teeth and gums.
Individual, not a template
Wishes, natural proportions, dental health and function belong together. A photograph or supposed ideal measurement does not establish a need for treatment.
Often confused
Smile line or smile arc?
Smile line here describes lip height and gum display. The smile arc follows the upper incisal edges in relation to the lower lip.
Quick answers
Does showing gum mean disease?
Not on its own. Gum visibility during smiling is initially a feature. Inflammation, symptoms and personal preferences need separate assessment.
Why does my smile look different in photographs?
Lip position, timing and camera angle affect the appearance. Different views and movement may therefore matter when planning treatment.
Must a high smile line be changed?
No. Looking different from a reference picture does not automatically justify treatment. If it bothers someone, the cause, options and limits can be discussed.
At the practice
For a personal conversation
An editorially suggested question for a conversation with Dr. med. dent. Niusha Barahmand Pour:
What affects how much of my teeth and gums is visible?
A natural smile involves more than one measurement.
Discuss your smile and wishesAppointment selection at DoctolibLearning layer for training & practiceUnderstand terminology and deepen knowledge
- Gingival display
- The amount of gum visible during smiling.
- Lip dynamics
- Movement of the lips during speech and smiling.
- Incisal edge
- The cutting edge of an incisor.
Make the distinction
Smile line here describes lip height and gum display. The smile arc follows the upper incisal edges in relation to the lower lip.
Sources and context
Editorial research: . General information, not an individual diagnosis or treatment recommendation. Teaching illustrations are simplified and do not depict a patient case.