A “gummy smile” is clinically referred to as excessive gingival display, describing a smile that shows a disproportionate amount of gum tissue above the upper teeth. Professionals generally consider the display excessive when three millimeters or more of gum tissue is visible between the top of the teeth and the lower edge of the upper lip during a full smile. This cosmetic presentation is a variation in facial anatomy, not a disease, but it can affect an individual’s self-perception and confidence. Addressing a gummy smile requires accurately diagnosing the underlying cause, as the most effective solution depends entirely on whether the issue relates to the skeletal structure, soft tissues, or the teeth and gums themselves.
Anatomical Factors Leading to Excessive Gum Display
Excessive gingival display is often multifactorial, resulting from a combination of issues related to bone, muscle, and soft tissue. Understanding the origin is the first step toward effective treatment, as causes are primarily grouped into three distinct categories.
One major contributor is Vertical Maxillary Excess (VME), a skeletal issue involving the overgrowth of the upper jawbone in the vertical direction. This excess bone length causes the upper teeth and surrounding gum tissue to sit lower than they should. This condition often makes the lower third of the face appear elongated and exposes a large amount of gum tissue.
Soft tissue factors frequently involve the upper lip, which can be anatomically short or hypermobile. An upper lip measuring less than 20 millimeters from the base of the nose to the lower edge is considered short, revealing more gum tissue by default. Hypermobility, or a hyperactive lip, is caused by overactive elevator muscles, such as the levator labii superioris, which pull the lip too high during a smile. This muscular overactivity creates a dynamic gummy smile that is only noticeable when fully expressing emotion.
The third category relates to dentoalveolar or gingival factors involving the teeth and surrounding gums. Altered Passive Eruption (APE) is a common cause where the gums fail to recede properly after the permanent teeth emerge. This leaves excess soft tissue covering the crown, making the teeth appear short, even though their true length is simply concealed. Excessive gum tissue growth, or gingival hyperplasia, sometimes caused by certain medications or inflammation, can also contribute to the display.
Minimally Invasive Correction Methods
When excessive gum display is caused by muscular hyperactivity or minor dental positioning issues, less invasive, often temporary, methods can be highly effective. These treatments focus on reducing the lip’s upward movement or subtly adjusting tooth position without major surgery.
Botulinum Toxin injections (Botox) are a popular non-surgical approach for treating gummy smiles caused by a hyperactive upper lip. The neurotoxin is precisely injected into the upper lip elevator muscles, such as the levator labii superioris, temporarily blocking nerve signals that cause excessive muscle contraction. This relaxation limits how high the lip can rise when smiling, effectively lowering the smile line. The procedure is quick, but the effect typically lasts only between four and six months, requiring repeat injections for maintenance.
Orthodontic treatment, using traditional braces or clear aligners, can address gummy smiles related to mild dentoalveolar extrusion or an over-erupted maxilla. In these cases, the teeth are positioned too far down, bringing the gum tissue with them. Modern orthodontics often utilizes Temporary Anchorage Devices (TADs), which are small skeletal implants. TADs provide a fixed anchor point for applying intrusive forces, allowing the orthodontist to push the entire upper arch of teeth and surrounding bone upward. This technique effectively reduces the gum show without resorting to jaw surgery.
Dermal fillers, typically hyaluronic acid, can also be strategically used to augment upper lip volume. The filler material is injected into the lip tissue to enhance its fullness, helping conceal a small amount of excessive gum tissue by creating a greater physical barrier. This method is generally reserved for minor cases where the lip is short or thin, providing a modest aesthetic improvement that lasts for several months.
Permanent Surgical Solutions
For cases rooted in skeletal malformation or significant soft tissue excess, permanent surgical procedures provide the most definitive and long-lasting correction. These interventions address the underlying structural issues rather than simply masking the effect.
For gummy smiles caused by Altered Passive Eruption, the solution is a procedure known as gingivectomy or aesthetic crown lengthening. A gingivectomy involves removing excess gum tissue to expose the full, natural length of the tooth’s crown. If the underlying alveolar bone contributes to the issue, the more comprehensive procedure, crown lengthening, is required. This involves reshaping both the gum tissue and the bone crest to establish the correct biological width around the tooth.
Lip repositioning surgery is a conservative procedure designed to permanently treat gummy smiles caused by hypermobile upper lips. The procedure involves removing a small strip of tissue from the inner surface of the upper lip and suturing the exposed area into a new, lower position. This modification creates a scar tissue barrier that physically restricts the upward pull of the lip elevator muscles, preventing the lip from rising too high during a smile.
The most extensive and permanent solution is orthognathic surgery, specifically a Le Fort I osteotomy with maxillary impaction, reserved for severe cases of Vertical Maxillary Excess (VME). This procedure involves surgically cutting and repositioning the entire upper jawbone (maxilla) upward to shorten the excessive vertical dimension. Moving the bone and teeth into a higher position drastically reduces the amount of gum visible and restores balance to the facial proportions.