Gummy Smile: Causes, Treatments, and Celebrity Transformations

What a Gummy Smile Is and How It Is Measured

A gummy smile is a smile that shows an unusually wide band of gum above the upper front teeth. Clinicians call it excessive gingival display, and the common working threshold is more than 3 to 4 millimetres of visible gum during a full, natural smile. Below that range, gum exposure is usually read as part of normal variation. The finding is aesthetic. A gummy smile does not damage the teeth or the gums by itself, and many people live comfortably with it for their whole lives.

The measurement matters because it turns a vague impression into a number that can be followed over time. The distance from the lower edge of the upper lip to the gum margin of the central incisors is recorded at rest and at full smile, often with photographs and short video. In the botulinum toxin studies pooled in one meta-analysis, patients qualified with more than 2 mm of gum exposure, and their mean display before treatment ranged from 3.5 to 7.2 mm (PubMed 36835971). A review of diagnosis and surgical care notes that many observers consider more than 4 mm of visible gingiva unattractive (PubMed 32111273).

People who ask about a gummy smile usually notice a few shared features, such as upper teeth that look short or square, a lip line that rises high when they laugh, and sometimes a gum line that is uneven from one side to the other. Some cases are symmetrical, others show more gum on one side. These features point toward different causes, and the cause decides the treatment. Two people with the same 5 mm of display can need entirely different care, which is why the first visit is spent on diagnosis before any option is discussed.

The Causes Behind Excess Gum Display

A gummy smile is rarely the result of one single factor. A review of its diagnosis lists altered passive eruption, lip length, lip hypermobility, incisal wear and crown length, vertical maxillary excess and gingival hyperplasia as contributing factors (PubMed 32111273). Each of these sits in a different layer of the face, so each is examined separately.

The first group is muscular. The levator muscles of the upper lip can lift the lip higher than average during a smile, exposing gum that stays hidden at rest. A second soft tissue group involves the gum itself. In altered passive eruption the gum and sometimes the bone fail to settle back to their usual position after the teeth erupt, so the teeth look short because part of the crown is still covered. A recent narrative review describes altered passive eruption and a hypermobile upper lip as the two major soft tissue causes of excessive gingival display (PubMed 37730094). Gum overgrowth, known as gingival hyperplasia, can add to this picture.

The third group is dental. Worn edges on the upper front teeth, or teeth that erupted less than usual, reduce the visible crown and make the gum band look wider. The fourth group is skeletal. In vertical maxillary excess the upper jaw has grown further downward than average and carries the gum line with it. Family resemblance is common, because lip length, tooth size and jaw growth are all partly inherited.

In growing children and teenagers, an orthodontic assessment can show early whether jaw growth, a deep bite or habits such as mouth breathing are contributing. Early findings help plan later care, though they do not always prevent a gummy smile from developing.

Botulinum Toxin and Lip Fillers

Botulinum toxin A is the most widely used non-surgical option when an overactive upper lip is the driver. The protein reduces the force of muscle contraction, so the lip rises less when the person smiles. The meta-analysis on this treatment reported the levator labii superioris, levator labii superioris alaeque nasi and zygomaticus minor as the muscles most often injected, with 1.25 to 7.5 units per side (PubMed 36835971).

The measured effect is modest but consistent. Across the pooled studies, gum display fell by a mean 2.51 mm at two weeks and 2.24 mm at three months (PubMed 36835971). The same review found that results gradually decrease over time, but they had not returned to their starting values after 12 weeks (PubMed 36835971). This means the injections are repeated if the patient wants to keep the effect. The review also notes that when the cause is vertical excess of the upper jaw, orthognathic surgery remains the structural solution, and that botulinum toxin suits borderline cases and cases driven by the lip muscles (PubMed 36835971).

Lip fillers raise a separate question. A filler placed in a way that lifts or shortens the upper lip can make a gummy smile more obvious. In selected cases, added volume can drape over the gum margin and reduce visible exposure. Because the effect depends on lip anatomy and on how strongly the muscles pull, filler is considered only after the cause of the gum display is clear, and it is planned together with any muscle treatment. A person who already has fillers should mention them at the first visit, since they change how the lip moves during the smile analysis.

Surgical and Gum Procedures

When the gum or the bone around the teeth is the cause, the treatment works on those tissues. Aesthetic crown lengthening removes excess gum and, where needed, reshapes the underlying bone so that the natural length of the tooth is exposed. A review of contemporary techniques describes aesthetic crown lengthening as the established surgical treatment for altered passive eruption, and lip repositioning surgery as the established treatment for a hypermobile upper lip (PubMed 37730094). Gum contouring with a scalpel or laser is a smaller version of this idea, used when only soft tissue needs trimming and the bone level is already correct.

Lip repositioning surgery changes where the inner lining of the upper lip attaches, which limits how far the lip can rise. Pooled data from eight studies showed a reduction of 2.87 mm at three months, 2.71 mm at six months and 2.10 mm at twelve months (PubMed 33325589). The authors describe an approximately 25% relapse after 12 months, and they found greater reduction at 6 months when a myotomy, a partial release of the lip muscle, was added to the procedure (PubMed 33325589). They recommend combining the surgery with periodontal, restorative or botulinum toxin approaches for more stable outcomes (PubMed 33325589).

Orthognathic surgery is the route for vertical maxillary excess. The upper jaw is repositioned under general anaesthesia after a phase of orthodontic preparation, and recovery takes longer than any of the procedures above. It changes facial proportions as well as the smile, so it is reserved for cases where the skeleton itself is the cause.

Orthodontics and Combined Smile Design

Orthodontic treatment helps when the bite or the vertical position of the front teeth contributes to the gum display. Braces or clear aligners can move teeth into a better position, and small temporary anchorage screws placed in the bone allow the orthodontist to move over-erupted upper front teeth upward. As the teeth move, the gum margin follows them. This approach is used in teenagers and in adults, and it is often combined with other steps. A published case report described incisor intrusion with miniscrews followed by periodontal surgery to lengthen the crowns, with a stable result at the 24 month follow-up (PubMed 32620481).

Many gummy smiles have more than one cause, so a plan often joins two or three treatments. Gum contouring can be paired with orthodontics when both the gum level and the tooth position need change. Lip repositioning can be followed by crowns or veneers when the teeth are also short or worn, so that the ratio of tooth to gum improves from both directions. Botulinum toxin is sometimes used before a permanent procedure to show the patient how a lower lip line will look.

This planning falls under aesthetic dentistry, where the smile is designed as a whole, including tooth length, gum line, lip movement and facial proportions. The order of steps matters. Gum and bone changes are usually completed before final restorations, because the restorations are shaped to the new gum margin. Photographs and a trial smile help the patient see the planned change before any irreversible step is taken.

Personal Choice and Public Visibility

Treating a gummy smile is a choice. Several well known public figures have smiles that show more gum than average; some have kept that smile as part of their appearance, while others have chosen treatment. Their examples show that a visible gum line can sit comfortably within an attractive smile, and that the decision rests with the person who wears it. Some patients who come for a consultation decide, after seeing the numbers and the options, that they prefer to leave their smile as it is.

For others the gum band is a real source of discomfort. People describe avoiding photographs, covering their mouth when they laugh or feeling self-conscious when speaking in public. These feelings deserve attention even though the condition is harmless for oral health, and they are a legitimate reason to seek treatment. Teenagers can be particularly sensitive to how their smile looks in photographs, which is one more reason to include them in the conversation about timing.

Some people come to the clinic with a more extensive change in mind, such as a full Hollywood Smile with veneers or crowns on the front teeth. In a gummy smile case, veneers alone do not reduce gum display, because they change the teeth and leave the lip and the gum level where they were. When a gummy smile and a wider cosmetic plan meet, the gum line is usually corrected first so that the new teeth are sized to their final frame. The expected result should be discussed in millimetres and in photographs, so that the patient knows in advance how much change each step can realistically bring.

Examination Findings That Guide the Choice

The choice of treatment depends on what the examination finds. The first question is which layer is responsible. If the teeth look short and the gum sits low over the crown, the dentist checks where the bone crest lies, usually with a periodontal probe and a radiograph, because this separates a gum only problem from one that also needs bone reshaping. If the teeth have normal length and the lip rises unusually high, the muscles are the likely driver. If the whole lower third of the face looks long and the gum display is large even at rest, the jaw is assessed for vertical excess.

The second question is how long the result should last. Botulinum toxin gives a measurable reduction that fades over months and needs repeat sessions (PubMed 36835971). Lip repositioning gives a longer effect with some relapse in the first year (PubMed 33325589). Crown lengthening and gum contouring change the tissues permanently once healing is complete, and orthognathic surgery changes the jaw itself.

The third question is recovery. Injections involve no downtime, gum procedures need a short healing period, and jaw surgery requires hospital care and weeks of recovery. At the consultation the smile is measured at rest and in full smile, photographs are taken, and the teeth, gums and lip movement are examined together. With those findings in hand, the options that fit the cause can be compared by their expected effect, their stability and the recovery they need, and the patient decides which one suits them.