Whether a few units can help depends entirely on why the gums show — and that is a question of muscle, lip or bone.
Can Botox fix a gummy smile? It can, when the cause is an overactive muscle that pulls the upper lip too high. A few units placed in the lip elevator muscles reduce that pull so the lip covers more of the gum. It does not help when the cause is a short upper lip, excess gum tissue or the position of the jaw bone.
What causes a gummy smile
The four main causes
A gummy smile is a symptom, not a diagnosis. It can come from an overactive upper lip elevator muscle, a naturally short upper lip, excess gum tissue covering the teeth, or the vertical position of the upper jaw.
Why the cause decides the treatment
Only the first of those is a muscle problem. Botulinum toxin softens muscle activity, so it addresses that cause and leaves the other three untouched.
How treatment works when muscle is the cause
Reducing the pull
Small amounts are placed in the muscles that lift the upper lip. With the pull reduced, the lip does not travel as far upward when you smile, so less gum is exposed. The Cleveland Clinic describes the underlying mechanism as a temporary block of the nerve signals that make a muscle contract.
Why the dose is tiny
These muscles are small and sit close to the muscles controlling the rest of your smile. A few units too many produces a flattened or asymmetric smile, so this is a precision treatment rather than a volume one.
Which causes respond
| Cause | Responds to Botox? | Usual approach |
|---|---|---|
| Overactive lip elevator muscle | Yes | Small dose in the lip elevators |
| Short upper lip | No | Surgical or filler opinion |
| Excess gum tissue | No | Dental — gum contouring |
| Short or worn teeth | No | Dental — restorative work |
| Vertical jaw position | No | Orthodontic or surgical opinion |
| Combination | Partly | Botox plus dental input |
Assessment, not assumption, decides which applies. Many gummy smiles have more than one cause.
What to expect from treatment
Realistic expectations:
- A reduction in gum show rather than complete elimination
- Onset from about day three, full effect at 10 to 14 days
- Duration of roughly three to four months
- A smile that still moves, if dosed conservatively
- Possible slight asymmetry at first, correctable at review
- A temporary odd feeling in the upper lip for a few days
Risks specific to this area
Smile asymmetry
The main area-specific risk. Because the muscles are small and paired, a slight difference in dose or placement between sides shows up immediately in the smile.
Lip function
Some people notice the upper lip feels different when speaking, whistling or drinking through a straw for a week or two. It settles as the effect balances out.
When to see a dentist instead
The honest referral
If your gum show comes from tooth length, gum tissue or jaw position, injecting the lip muscles will not help and a dental or orthodontic assessment is the right next step. A clinic that treats every gummy smile with toxin is not assessing properly.
Sometimes both
Where there is a genuine muscle component alongside a dental one, treating the muscle can still be worthwhile as part of a combined plan.
Step-by-step: getting a gummy smile assessed
How to approach it:
- Video yourself smiling and laughing naturally, not posing, in daylight.
- Note how much gum shows and whether it is even on both sides.
- Book a consultation and ask which of the causes your doctor identifies.
- Ask directly whether a dental opinion would help before treatment.
- If muscle is the cause, agree a conservative starting dose.
- Avoid alcohol and blood-thinning supplements for 24–48 hours beforehand, where appropriate.
- Review at about two weeks to check smile symmetry before any top-up.
Gummy smile assessment at LIV Clinic
Cause before treatment
At LIV Clinic on Koh Samui and Koh Phangan, Dr. Narathai assesses which of the causes is driving your gum show and will refer for a dental opinion rather than treat a problem that injectables cannot solve.
Read next
See our Botox and wrinkle programme, compare with a lip flip versus lip filler, or book a consultation.
Frequently asked questions
Can Botox fix a gummy smile?
It can when the cause is an overactive muscle pulling the upper lip too high. It does not help when the cause is a short upper lip, excess gum tissue, short teeth or jaw position.
How many units are used for a gummy smile?
Very few. The lip elevator muscles are small and sit near the muscles controlling the rest of your smile, so this is a precision treatment where a few units too many causes problems.
How long does it last?
Usually about three to four months, in line with other treatment areas. The effect builds over 10 to 14 days and longevity varies between individuals.
Will my smile look strange?
Not if dosed conservatively. The main risk is slight asymmetry between the two sides, which is usually correctable at a two-week review.
How do I know whether my gummy smile is muscle-related?
An in-person assessment is the only reliable way. Filming yourself smiling naturally helps, but distinguishing muscle pull from lip length or gum tissue needs an examination.
Should I see a dentist first?
If your gum show relates to tooth length, gum tissue or jaw position, yes. A clinic that proposes injectables for every gummy smile without assessing the cause is not assessing properly.
Safety and consultation
Gummy smile Botox is a prescription medical treatment and, like any injectable, carries some risk — common temporary effects can include redness, swelling, bruising, mild headache or a short-lived heaviness, and less common reactions such as temporary eyelid or brow droop are possible. Results vary from person to person, and no specific outcome can be promised. This article is general information, not medical advice.
At LIV Clinic, every treatment begins with an in-person assessment by Dr. Narathai Vichienkalayarut, M.D., who reviews your skin, medical history and goals before recommending a personalized plan. Book a consultation to find out whether this treatment suits you.
LIV Clinic — “Live Your Life Young”
Doctor-led aesthetic and wellness clinic on Koh Samui and Koh Phangan, serving both international visitors and local residents.
Koh Samui (Bophut): 1/63 Thaweeratpakdee Rd, Bo Put, Koh Samui, Surat Thani 84320 · Tel 065-996-4242
Koh Phangan: 116/16 Moo 1, Koh Phangan, Surat Thani 84280 · Tel 093-254-5259
LINE: @Livclinic · Book a consultation
Explore our Botox and wrinkle and dermal filler services.
ฆสพ.สฎ. 78/2567