An oral melanotic macule is a small, flat, brown to black spot in the mouth caused by a harmless build-up of pigment, and it is the most common pigmented spot of its kind. It behaves like a freckle inside the mouth. It is benign, it does not cause symptoms, and it most often appears on the lower lip or gum. As with any pigmented mark, the reason a dentist looks carefully is to make sure it is a simple macule and not something that needs further attention.
Key takeaways
- A melanotic macule is a flat, well defined brown or black spot caused by increased melanin pigment in the surface tissue.
- It is completely benign and is the most common pigmented lesion of melanocytic origin in the mouth.
- The lower lip and the gums are the usual locations, and it is more common in women.
- Unlike a skin freckle, sun exposure is not the cause, and trauma may play a role in some cases.
- A single pigmented spot that is new, growing, or changing should be biopsied to confirm it is harmless.
What it looks like
A melanotic macule is typically flat, meaning it is level with the surrounding tissue rather than raised. It is usually well defined with even borders, uniform in colour, and small, commonly under one centimetre across. Colours range from light brown to almost black. It does not hurt, does not change texture, and tends to stay the same over long periods. The lower lip is a classic site, along with the gums, inner cheek, and palate.
What causes mouth pigmentation
Pigment in the mouth comes from melanin, the same substance that colours skin. A melanotic macule is simply a localised patch where pigment producing cells have deposited a little extra melanin. The exact trigger is often unclear. Trauma has been suggested as a factor in some cases, while sun exposure, unlike on the lips outside the mouth, is not relevant to spots on the inner tissues. Some people also have naturally more pigmented gums as a normal racial variation, which is a diffuse, even colouring rather than a single spot. Certain medicines, smoking, and some medical conditions can also increase mouth pigmentation more broadly.
The one rule that guides assessment
Most pigmented spots in the mouth are harmless, and the melanotic macule is the most common. The important principle is that oral melanoma, though very rare, has no reliable features that separate it from a benign spot on sight alone. For that reason, the guiding rule is that any solitary pigmented spot that is persistent and of uncertain diagnosis should be biopsied. A stable, long standing, evenly coloured spot may reasonably be monitored, but anything new or changing is confirmed with a sample.
| Feature | Typical melanotic macule | Reason to biopsy |
|---|---|---|
| Shape | Flat, even, well defined | Raised or irregular border |
| Colour | Uniform brown to black | Mixed or uneven colour |
| Change | Stable over time | New, growing, or darkening |
| Number | Usually single | Multiple spots with other symptoms |
How it is diagnosed and managed
Your dentist takes a history, looks at the spot, and considers your medicines and habits. If the appearance and story clearly fit a melanotic macule and it has been stable, monitoring at routine visits may be all that is needed. When there is any uncertainty, or if the spot is new or changing, a small biopsy provides a definitive answer. This is a minor procedure under local anaesthetic. Once confirmed as benign, a melanotic macule needs no further treatment, though it can be removed for cosmetic reasons if it is in a visible spot.
General cost guide
The figures below are general market ranges across Australian clinics, not a Lumi quote.
| Item | General cost guide (AUD) |
|---|---|
| Examination and diagnosis | $60 to $250 |
| Soft tissue biopsy (if needed) | $200 to $500 |
You can see current offers on our current deals page, and we will always provide a written estimate first.
When to have a spot checked
See a dentist if a pigmented spot is new, is enlarging, has an uneven colour or border, becomes raised, or bleeds. These features usually turn out to be harmless, but they are exactly when confirming the diagnosis matters. For related reading, see our guides to an amalgam tattoo, which is another common cause of a dark mark, white patches in the mouth, and how an oral cancer screening is carried out.
Frequently asked questions
Is an oral melanotic macule dangerous?
No. It is a benign patch of extra pigment, similar to a freckle. The attention it receives is only to confirm it is not a rarer pigmented condition that happens to look alike.
What is the difference between a melanotic macule and an amalgam tattoo?
A melanotic macule is made of natural melanin pigment, while an amalgam tattoo is caused by tiny metal particles from a silver filling. They can look similar, and a dentist distinguishes them by history, position, and sometimes a biopsy.
Do I need it removed?
Not for health reasons once it is confirmed benign. It can be removed cosmetically if it is in a noticeable place, but this is optional.
Why did it appear on my lip?
The lower lip is a common site for these spots. The exact cause is often unclear, and unlike freckles on the skin, sun exposure is not the driver for spots inside the mouth.
Should I worry if I have several dark spots?
Multiple pigmented spots, especially with other symptoms, are worth mentioning to your dentist or doctor, as they occasionally point to a broader condition that is worth reviewing.
If you have noticed a brown or dark spot in your mouth, the team at Lumi Dental in Melrose Park can assess it and reassure you or investigate further. Learn more about our general dental care or view our current deals.
This article is general information only and is not a substitute for personalised advice from a dental or medical professional. If you notice a spot that is new, changing, or growing, please arrange an assessment.
