If you have ever felt that your smile shows "too much gum," you are not alone, and you are not imagining things. A gummy smile is a recognized clinical concern with its own research literature. The useful news is that there are several ways to treat it. The important news is that the right one depends entirely on why it happens.
A lot of online content treats "gum contouring" as the universal fix. Sometimes it is exactly right. Sometimes it addresses only part of the problem, or the wrong part. This guide explains the main causes, the treatments matched to each, and the questions that help you get an accurate diagnosis before anyone picks up an instrument.
What counts as a gummy smile?
Dentists often call it excessive gingival display. A 2024 review in the journal Cureus describes gum display of 1 to 3 mm as typical when smiling and says display above about 3 mm is generally considered less attractive. The same review puts prevalence at around 7% of adults, noting it is more common in women (Abu Alfaraj et al., Cureus, 2024).
Those numbers are a clinical reference point, not a beauty standard you have to meet. Plenty of people with more gum display love their smiles. This article is for those who don't and want to understand their options.
The causes: why gums show
The Cureus review emphasizes that gummy smiles are usually multifactorial: more than one cause is often involved, and treatment should follow the cause (Abu Alfaraj et al., 2024). Here are the main ones, in plain English.
Gums that never fully moved up (altered passive eruption)
As adult teeth come in, the gum line normally settles higher up on the tooth. In some people it stays lower, covering more of the tooth's surface. Teeth can look short and square, and more gum shows when smiling. This is a gum-and-tooth issue.
An upper lip that lifts a lot (hypermobile upper lip)
Some upper lips simply rise higher than average when you smile. The review describes this as lip movement of more than about 8 mm from rest to full smile, and reports that it was present in a large majority of adults with gummy smiles in the studies it cites (Abu Alfaraj et al., 2024). Here the teeth and gums may be perfectly proportioned; it is the lip's movement creating the display.
Upper jaw growth (vertical maxillary excess)
When the upper jaw has grown longer vertically, more gum shows even at rest. This is a skeletal cause, and it is the one most likely to need more extensive treatment.
A short upper lip
A shorter-than-average upper lip can expose more gum. The review notes this is a less common cause, reported in under 10% of cases (Abu Alfaraj et al., 2024).
Teeth and gums that have drifted down, or overgrown gum tissue
Front teeth that have over-erupted can bring the gum line down with them. Some medications can also cause gum tissue to overgrow. Both are listed among dental causes in the review.
Matching the treatment to the cause
These pairings follow the treatment logic described in the 2024 review (Abu Alfaraj et al., 2024). Many real cases combine two or more approaches.
Gum contouring and crown lengthening
When the problem is gum tissue covering too much of the tooth, reshaping the gum line can reveal more of the natural tooth and make teeth look longer and better proportioned. In simpler cases, only gum tissue is reshaped. When the bone sits too close to the gum line, a periodontist or dentist may also need to reshape bone, which is usually called crown lengthening.
This is the area where cosmetic dentistry and periodontics overlap most. It is also where gum contouring is often paired with veneers or bonding: once the gum line is corrected, front teeth can be lengthened or reshaped to fit the new proportions. If veneers are part of the plan, ask whether gum work should come first and how long healing will take before final shade and shape decisions.
"Will the gums grow back?"
Ask your dentist how they assess where the bone sits relative to the gum line before contouring. That assessment helps determine whether gum-only reshaping is likely to hold or whether a more involved procedure is needed. A careful clinician will explain this to you before treatment.
Botulinum toxin for an active upper lip
For gummy smiles driven mainly by lip movement, small injections of botulinum toxin can reduce how high the lip lifts. The 2024 review describes peak effect at around 48 hours and effects lasting roughly three to six months (Abu Alfaraj et al., 2024). That makes it a reversible, temporary option, and some people use it as a way to "preview" how a lower lip line would look.
The trade-off is upkeep: results fade, so repeat treatments are needed to maintain them. Injections should only be given by an appropriately trained and licensed professional.
Lip repositioning surgery
Lip repositioning is a surgical procedure that limits how far the upper lip can rise. The review describes it as a main treatment for an overly mobile upper lip and for milder jaw-related cases, but not advised when vertical jaw excess is large (more than about 8 mm) or when the band of firm gum tissue is narrow (Abu Alfaraj et al., 2024).
What does the research say about results? Studies summarized in the review generally report reductions in gum display of roughly 2 to 3.5 mm, with some return of display over the following months. For example, one review cited there found average reductions of about 2.9 mm at three months falling to about 2.1 mm at a year (Abu Alfaraj et al., 2024).
That gradual return, called relapse, is the main limitation. The review describes techniques that aim to reduce it, such as adding muscle procedures or specialized suturing, and also notes that the evidence for some of these is not conclusive. Short-term numbness and other complications are possible. If you're considering this procedure, ask your clinician directly about relapse and how they manage it.
Jaw surgery
When a gummy smile is caused mainly by the upper jaw's vertical growth, orthognathic surgery addresses the skeletal cause directly. The review calls it the primary treatment for this cause, but also notes it is complex, invasive and comes with significant recovery, which is why many patients prefer to avoid it (Abu Alfaraj et al., 2024). This is a decision for a specialist team, usually including an orthodontist and an oral and maxillofacial surgeon.
Getting the diagnosis right
Because treatment follows cause, the most valuable part of your consultation is the assessment. A thorough evaluation often includes:
- Photos and video of your smile at rest, while talking, and in a full natural smile.
- Measurements of tooth length and width, and how much tooth is hidden under the gum.
- Measurement of how far your upper lip moves from rest to smile.
- X-rays to see where the bone sits.
- A look at your bite and jaw relationships.
- A review of your medications if gum overgrowth is suspected.
If a plan is proposed after only a quick glance, it is reasonable to ask how the cause was identified. And if one clinician suggests gum contouring while another suggests lip treatment or orthodontics, that may simply reflect a multifactorial case. A second opinion can help.
A note on expectations
Even well-chosen treatments have limits. Gum procedures change the gum line but not lip movement. Lip treatments change lip movement but not tooth proportions. Botulinum toxin wears off. Jaw surgery is a big undertaking. Many successful outcomes come from combining modest changes rather than chasing a dramatic single fix.
It's also worth remembering that a "gummy" smile is often a full, generous smile. The aim of treatment is not to make you smile less; it is to help you feel comfortable smiling freely.
Questions to ask
- What do you think is causing my gum display, and how did you determine that?
- Is more than one cause involved?
- Will I need gum-only reshaping, or crown lengthening with bone reshaping?
- If my lip is a factor, what are the pros and cons of injections versus surgery?
- What results and relapse should I realistically expect?
- Should gum work happen before veneers or bonding, and how long should I wait between them?
- Who will perform each part, and what is their training?
The bottom line
A gummy smile is a common and treatable concern, but it isn't one condition with one fix. Gum tissue, lip movement, tooth position and jaw growth can each play a part. Start with a thorough diagnosis, understand which causes apply to you, and choose treatments that address those causes, with honest expectations about what each can and can't change.
Curious about gum contouring or other options?
Compare practices that start with a proper diagnosis of why your gums show, and that explain every option before recommending one.
See how it worksRemoving excess gum tissue is generally a lasting change, but stability depends on where the underlying bone sits. That's why dentists assess bone level before contouring and sometimes recommend crown lengthening instead. Ask your clinician how they evaluate this for your teeth.
A 2024 review in Cureus describes effects lasting roughly three to six months, with peak effect around 48 hours after injection. Repeat treatments are needed to maintain results.
Studies summarized in a 2024 review report meaningful reductions in gum display, but also gradual relapse over months. Various techniques aim to reduce relapse, with mixed evidence. Discuss expected stability directly with your surgeon.
Veneers alone can't move the gum line or change lip movement. They're often combined with gum contouring when short-looking teeth are part of the problem, so teeth can be reshaped to match a corrected gum line.
It depends on the cause. Gum procedures are often done by periodontists or experienced cosmetic dentists; orthodontic causes involve an orthodontist; jaw surgery involves an oral and maxillofacial surgeon. Complex cases are often planned by a team.