Excessive gingival display, commonly known as a “gummy smile,” is a condition where a prominent amount of gum tissue is visible above the upper teeth when a person smiles. While 1 to 2 millimeters of gum showing is considered normal, the display is classified as excessive when it reaches 3 to 4 millimeters or more. This anatomical trait occurs in an estimated 10% of young adults and is primarily treated as an aesthetic concern. Most individuals seek consultation to achieve a more balanced appearance between the teeth, gums, and lips.
Does a Gummy Smile Impact Oral Health
A gummy smile is generally a nonpathological condition, meaning it does not pose a direct threat to overall oral health. The visibility of the gums itself is not detrimental to the teeth or jaw structure. However, the underlying cause of the excessive gum display can sometimes be linked to functional issues that compromise oral hygiene.
If the gum tissue is significantly overgrown, a condition known as gingival hyperplasia, it can create deep pockets around the teeth. These areas are difficult to clean effectively with routine brushing and flossing. This difficulty leads to a buildup of plaque and bacteria, increasing the risk of inflammation, gingivitis, and periodontal disease.
A gummy smile sometimes results from an underlying skeletal issue or a misaligned bite (malocclusion). When the teeth and jaws do not meet correctly, this imbalance can cause uneven wear on the teeth or muscle strain. In these instances, the condition is more than cosmetic and may require treatment to prevent long-term dental complications.
Anatomical Reasons for Excessive Gum Display
A gummy smile is a symptom with three distinct anatomical origins, which often occur in combination.
Soft Tissue Issues
The first origin relates to the soft tissue, specifically the upper lip’s movement and length. Some people have a hyperactive upper lip, where the elevator muscles, such as the levator labii superioris, pull the lip too high when smiling. This exposes an excessive amount of gum tissue.
Dental and Gingival Tissues
A second common cause involves the dental and gingival tissues themselves. This can manifest as altered passive eruption, a developmental issue where the gums fail to recede correctly after the adult teeth have emerged. This leaves the clinical crowns partially covered by gum tissue, making the teeth appear shorter. Gingival hyperplasia, an abnormal overgrowth of the gum tissue, can also be caused by certain medications, systemic conditions, or chronic inflammation.
Skeletal Issues
The third and most structurally complex origin is skeletal, known as Vertical Maxillary Excess (VME). In this condition, the upper jawbone (maxilla) has grown too long in the vertical dimension. This overgrowth causes the entire upper dental arch and surrounding gum tissue to sit lower than typical. This results in an elongated appearance to the midface and a pronounced display of gums upon smiling.
Options for Reducing Gum Visibility
The treatment path for reducing gum visibility depends entirely on correctly identifying the underlying cause, requiring a thorough examination by a dental specialist.
Treating Hyperactive Lip Muscles
For cases rooted in hyperactive lip muscles, the least invasive option is botulinum toxin (Botox) injections. The neurotoxin is injected into the hyperactive muscles to temporarily relax them, limiting the upward movement of the upper lip during a smile. This non-surgical solution is quick, but the effect is temporary, requiring repeat treatments every three to six months to maintain the result.
Treating Excess Gum Tissue
When the cause is an overgrowth of gum tissue, such as altered passive eruption or gingival hyperplasia, a dental procedure is the standard approach. A gingivectomy, or gum contouring, is a surgical procedure that uses a scalpel or laser to remove the excess soft tissue and sculpt a balanced gum line. If the issue involves the underlying bone, a crown lengthening procedure is performed. This involves removing a small amount of both gum tissue and bone to fully expose the anatomical tooth crown.
Treating Skeletal Issues
More significant anatomical issues, such as jaw misalignment or excessive tooth eruption, require complex interventions. Orthodontic treatment, using braces or clear aligners, can gently push the upper teeth and their supporting bone structure further into the jaw. For severe skeletal imbalances like Vertical Maxillary Excess, orthognathic surgery, specifically a Le Fort I osteotomy, may be necessary to surgically reposition the entire upper jaw upward. These surgical options offer a permanent solution to structural problems.