What Causes a Gummy Smile? Muscle Anatomy and How Botox Can Help

A gummy smile shows more of the upper gums than you would like when you fully smile. It is common, it is not a health problem, and in most cases it traces back to how one small muscle behaves, not to your teeth or your gums themselves. Understanding the cause is what makes the treatment options make sense.

This guide walks through what actually causes a gummy smile, the anatomy behind it, and how a few units of Botox can soften the look when an overactive muscle is the reason. Outcomes differ from person to person, so treatment is always planned during a consultation rather than promised in advance.

In a short video on the anatomy of a gummy smile, Lily Zelaya, RN, an aesthetic nurse injector at Express Med Spa, explains the exact muscle responsible and how a small, targeted dose of Botox may relax it. This article expands on that explanation and covers the other possible causes, treatment options, and what to expect.

What Causes a Gummy Smile?

The most common cause of a gummy smile is an overactive muscle that lifts the upper lip too high when you smile, exposing more of the gum line above your teeth. When this lip-elevator muscle is especially strong or hyperactive, the upper lip rises further than average and reveals more gum tissue. Less often, a gummy smile is driven by the amount or shape of the gum tissue, the length of the upper lip, the size and position of the teeth, or the underlying jaw and bone structure. Many people have a combination of these factors, which is why an in-person assessment matters.

Because the muscle-driven type is the most frequent, it is also the type most often improved with a few units of Botox. When gum tissue, tooth position, or bone structure is the main driver, other approaches may fit better, and your provider can help you understand which pattern you have.

Is a Gummy Smile Something You Need to Fix?

A gummy smile is a cosmetic characteristic, not a medical problem, and plenty of people never think twice about it. There is nothing you have to change. For those who feel self-conscious about how much gum shows when they smile or laugh, though, softening it is a personal choice, and it is worth knowing that a subtle, muscle-based option exists.

The goal of treatment is balance, not a dramatic change. When Botox is used for a muscle-driven gummy smile, the aim is to reduce how high the lip lifts just enough that the smile looks more even, while still moving and looking natural. What counts as the right amount of gum is subjective, so the plan is built around what you want to see.

The Muscle Behind a Gummy Smile

The muscle most responsible for a gummy smile is the levator labii superioris alaeque nasi — often noted as the longest muscle name in the human body. It runs alongside the nose, originating at the maxilla near the inner corner of the eye and traveling down to attach into the upper lip.

Its job is to lift the upper lip when you smile and to help flare the nostrils. When this muscle is especially strong or overactive, it pulls the upper lip higher than desired, which exposes more of the upper gums. That single mechanism explains why relaxing the muscle, rather than changing the teeth or gums, is often enough to soften the look.

Other Causes of a Gummy Smile

Muscle activity is the most common driver, but it is not the only one. A full smile is the product of muscle, lip, gum, tooth, and bone all working together, so a gummy smile can come from any of the following, sometimes in combination.

A Short or Hyperactive Upper Lip

A naturally short upper lip, or one that moves a long distance when you smile, can reveal more gum even with normal muscle strength. In these cases the lip simply does not cover as much of the gum line at rest or in motion.

Excess or Uneven Gum Tissue

Sometimes the gums themselves cover more of the tooth than average, or sit unevenly, so more gum shows when you smile. This is a tissue pattern rather than a muscle pattern, and it is assessed differently.

Tooth Size and Position

If the upper teeth are shorter, worn, or positioned in a way that leaves more gum exposed above them, the smile can read as gummy even when the lip and muscle are behaving normally.

Jaw and Bone Structure

The way the upper jaw is shaped and positioned influences how much gum is visible. Skeletal factors are less common as a sole cause, but they can contribute to the overall look and usually require a different specialty to address.

How Botox Softens a Gummy Smile

When an overactive lip-elevator muscle is the cause, a few units of Botox injections placed near the lateral sides of the nostrils can gently relax that muscle. With the muscle calmed, the upper lip does not lift quite as high when you smile, so less gum shows and the smile typically looks softer and more balanced while still moving naturally.

It is a small, targeted treatment. Botox is a neurotoxin that temporarily reduces muscle activity in the exact area it is placed, which is why precise placement by a trained injector matters. Because the effect is on muscle movement rather than on gum tissue or teeth, it works best for the muscle-driven type of gummy smile. Results vary from person to person, and your provider will assess whether this approach fits your anatomy.

How Many Units of Botox for a Gummy Smile?

A gummy smile correction generally uses only a few units of Botox, placed on each side near the base of the nose. It is one of the smaller injectable treatments by volume. The exact number of units depends on your muscle strength, your anatomy, and how much gum shows when you smile, so it is reviewed and confirmed at your consultation rather than set as a fixed figure. Starting conservatively and adjusting at a follow-up is a common, cautious approach.

Is Gummy Smile Botox Permanent? How Long It Lasts

Botox is not permanent. Its effect on the lip-elevator muscle typically lasts a few months before the muscle gradually returns to its previous activity, at which point the gummy smile slowly comes back unless the treatment is repeated. Many clients schedule maintenance sessions to keep the result, and duration varies from person to person. The temporary nature is also an advantage: if you want to adjust the look, you are never locked in.

Botox vs. a Lip Flip and Other Options

Botox for a gummy smile relaxes the muscle that lifts the upper lip. A lip flip uses a small amount of Botox in the upper lip to gently roll a bit more lip outward, which is a different goal and a different placement, though both use the same neurotoxin. Some people are candidates for one, some for the other, and some for a combination, depending on what they want to change.

When the gummy smile is driven mainly by gum tissue, tooth size, or jaw structure rather than muscle, non-injectable approaches from a dental or surgical specialist may be more appropriate. The purpose of a consultation is to identify the real driver so the plan matches your anatomy instead of forcing one tool to fit every cause.

Who Is a Good Candidate for Gummy Smile Botox?

The best candidates are people whose gummy smile comes mainly from an overactive lip-elevator muscle, since that is exactly what Botox acts on. If your upper lip lifts high and reveals a band of gum when you smile fully, muscle activity is often the driver, and a small dose may help. People whose gum display is driven mostly by gum tissue, tooth size, or jaw structure are usually better served by other options.

A consultation is how candidacy is determined. Your provider watches how your lip moves when you smile, considers the other possible causes, and reviews your history before recommending anything. As with any neurotoxin treatment, it is not right for everyone, and suitability, dosing, and expected outcome are always individualized. Results vary.

What to Expect During and After Treatment

The treatment itself is quick. After confirming your plan, your provider places a few small injections near the base of the nose, and most appointments for this area are brief. There is generally no significant downtime, so many people return to their usual day, following whatever aftercare guidance their provider gives.

Botox does not work instantly. The muscle-relaxing effect usually develops over several days, so the softer smile appears gradually rather than the same day, and the full result settles in within a couple of weeks. Because the change is progressive and subtle, a follow-up is a good time to review the outcome and decide whether any small adjustment is worthwhile. Individual timing and results vary.

What Gummy Smile Botox Costs

Because a gummy smile correction is a Botox treatment, it is priced the same way as our other neurotoxin services. At Express Med Spa, Botox and Xeomin are from $10.95 per unit. Pricing varies based on the number of units needed and the treatment areas selected. Your total cost will be reviewed and confirmed at your complimentary consultation. Pricing is subject to change.

Since a gummy smile correction usually uses only a few units, it tends to sit at the lower end of injectable pricing, but the exact total always depends on your individual plan. Prices are subject to change.

Meet Your Provider: Lily Zelaya, RN

The gummy smile anatomy in the companion video is explained by Lily Zelaya, RN, an aesthetic nurse injector at Express Med Spa in La Grange, IL. As a registered nurse and aesthetic injector, she focuses on precise, natural-looking injectable treatments and on helping clients understand the anatomy behind their results before anything is planned.

Where to Get Gummy Smile Treatment Near You

Express Med Spa offers Botox and injectable consultations at four Chicagoland locations: Frankfort, La Grange, Shorewood, and Chicago (Mount Greenwood). Each location can assess whether your gummy smile is muscle-driven and whether a few units of Botox may help.

When you are ready, you can book a complimentary consultation online to review your smile, discuss the cause, and get a personalized plan. Results vary, and everything is confirmed with your provider before treatment.

Frequently Asked Questions