A traumatic fibroma, also called an irritation fibroma, is a harmless firm lump inside the mouth that forms in response to repeated biting, rubbing, or injury. It is one of the most common soft tissue growths in the mouth. It is not cancer, it does not spread, and it happens because the tissue has thickened to protect itself from ongoing trauma. The catch is that it will not shrink away on its own while the source of irritation continues.
Key takeaways
- A traumatic fibroma is a benign overgrowth of fibrous tissue caused by chronic irritation, most often from biting the cheek or lip.
- It appears as a smooth, firm, dome shaped lump, usually the same colour as the surrounding lining or slightly paler.
- The inside of the cheek along the biting line is the most common site, followed by the lip, gum, and sides of the tongue.
- The reliable fix is to remove the lump and, just as importantly, stop the habit or fix the sharp edge that caused it.
- Any lump that is growing, ulcerated, or does not fit this simple picture should be assessed to confirm the diagnosis.
Why a fibroma forms
Soft tissue in the mouth is resilient, but it does not enjoy being bitten or rubbed day after day. When a spot is repeatedly traumatised, the body lays down extra collagen to reinforce it. Over weeks to months, that reinforced tissue builds into a small firm nodule. Common sources of the trauma include a cheek or lip biting habit, a sharp or chipped tooth, a rough edge on a filling or crown, and dentures that rub. Because the lump then sits right in the path of the teeth, it often gets bitten again, which is why it tends to persist.
What it looks and feels like
A traumatic fibroma is typically a smooth, round or oval bump that feels firm rather than soft or fluid filled. It is usually painless unless it is being actively bitten. The surface is often the same pink as the nearby lining, though constant biting can make the top look paler or slightly rough. Most are only a few millimetres across, although some grow larger over time. It does not bleed spontaneously and does not change colour dramatically.
The single rule that decides success
Removing a fibroma is straightforward, but the one thing that decides whether it comes back is dealing with the cause. If the lump is taken off but the sharp tooth, rough restoration, or biting habit remains, the tissue can simply build up again in the same place. That is why treatment always pairs removal with fixing the source of irritation. Recurrence is uncommon precisely when the trigger is addressed.
| Feature | Typical traumatic fibroma | Worth a closer look |
|---|---|---|
| Feel | Firm, smooth, dome shaped | Hard, fixed, or irregular |
| Colour | Same as lining, sometimes paler | Red, dark, or mixed colour |
| Surface | Intact and smooth | Ulcerated or bleeding |
| Growth | Slow or stable | Rapidly enlarging |
How it is treated
The definitive treatment is a small surgical excision, where the lump is removed under local anaesthetic. The tissue is usually sent to a laboratory to confirm the diagnosis, which is routine good practice for any lump that is removed. Healing is generally quick and uncomplicated. Alongside removal, your dentist will address whatever caused it, such as smoothing a sharp tooth, adjusting a rough filling or denture, or helping you become aware of a cheek biting habit. Without that second step, the fibroma has a higher chance of returning.
Can you prevent one?
Often, yes. Keeping up regular check-ups means sharp teeth and rough restorations get smoothed before they cause chronic trauma. If you know you bite your cheek or lip, mention it, as a nightguard or simple habit awareness can help, especially if the biting happens during sleep or concentration. Well fitting dentures that do not rub also reduce the risk. Our guide to harmless lumps and spots on the lips covers other benign findings people sometimes worry about.
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 |
| Minor surgical excision with biopsy | $250 to $600 |
| Adjusting a sharp tooth or filling | $50 to $200 |
You can view current new patient offers on our current deals page, and we will always provide a written estimate before any procedure.
When to get a lump checked
Have any mouth lump assessed if it is growing, if it becomes hard or fixed, if the surface breaks down or bleeds, or if it does not settle after the likely cause is removed. Most are harmless, but confirming that is worthwhile. For related reading, see our guides to mucous cysts on the lip, swellings under the tongue, and white patches in the mouth.
Frequently asked questions
Is a traumatic fibroma cancer?
No. It is a benign build-up of fibrous tissue and does not turn into cancer. Removed tissue is still checked in a laboratory as standard practice.
Will it go away if I stop biting the area?
Stopping the trauma prevents it getting worse, but an established fibroma usually stays until it is removed. The tissue has already thickened and does not simply melt away.
Does removing a fibroma hurt?
The area is numbed with local anaesthetic, so the procedure itself is comfortable. Any tenderness afterwards is usually mild and settles within days.
Why does my fibroma keep coming back?
Recurrence almost always means the original cause is still present, such as a sharp tooth or an ongoing biting habit. Fixing that source is the key to stopping the cycle.
Can children get a fibroma?
Yes, they can develop in anyone who repeatedly bites or irritates an area. The same approach applies, remove it if needed and address the cause.
If you have a firm lump inside your cheek or lip that will not settle, the team at Lumi Dental in Melrose Park can assess it and treat it if needed. Learn more about our general dental care or see our current offers.
This article is general information only and is not a substitute for personalised advice from a dental or medical professional. If you have a lump that is growing or changing, please arrange an assessment.
