Why do I keep getting a soft lump inside my cheek or lip?

Imagine this: There's a spot inside your cheek or lip that won't leave you alone. It flattens out for a few days, then, like clockwork, that bump is back. If that happens to you, it might be a mucocele, which forms when saliva collects under your mouth's lining, but repeated rubbing can cause something similar. Because different mouth growths can look alike, a returning lump should be checked by a dental provider. 

What you will learn in this article: 

• Mucoceles often form after biting or injuring a tiny salivary gland, especially in the lower lip. 

• Repeated rubbing from a tooth, filling or dental appliance can create a different type of lump. 

• Any lump that keeps returning, grows or lasts longer than two weeks needs a dental exam. 

• Treatment depends on the cause and may include removing the source of irritation or the lump itself.  

If you're unsure why a lump inside your cheek or lip keeps coming back, schedule an appointment with an Aspen Dental provider. Your care team can look at the area and explain what might be causing it. 

What causes a soft lump that keeps coming back? 

Several problems can cause a soft lump inside your cheek or lip. The American Academy of Pediatric Dentistry explains that saliva-related lumps can form when a small duct tears and leaks or when mucus collects behind a blocked duct.¹ 

Could it be a mucous cyst from biting your cheek? 

A mucocele can form when biting or another injury damages a tiny saliva duct. Saliva then collects beneath the lining of your mouth and creates a soft bump. Mucoceles often form on the lower lip, but they can also appear inside the cheek. The bump may look clear or blue. It may flatten after it opens and then fill again. If you keep biting the same spot, the area may continue to get irritated. 

Could a blocked salivary gland duct be the cause? 

Saliva travels through tiny tubes called ducts. If a duct becomes blocked, mucus can collect inside it and cause swelling. The lump may sometimes change in size around mealtime. A dental provider can examine the area and determine whether a saliva duct or gland may be involved. 

Could it be an irritation fibroma? 

An irritation fibroma is another possible cause. It is a soft-tissue growth rather than a saliva-filled mucocele. When a dental provider is confident that the growth is benign, the entire lesion may be removed so the tissue can be examined.² 

Is a recurring soft lump inside the cheek or lip serious? 

Mucoceles and irritation fibromas are benign types of mouth lesions. Still, a lump should be checked if it keeps returning, grows, feels hard, changes color, bleeds or does not heal. The American Association of Oral and Maxillofacial Surgeons notes that any suspicious mouth lesion still present after two weeks should be considered for a biopsy to rule out something more serious.² 

A soft lump is different from a hard lump on your gum, which can have its own causes and warning signs. If you notice blood blisters instead of a clear or flesh-colored bump, they may have a different cause. 

What can you expect if you see a dental provider about the lump? 

A dental provider will look closely at the lump. They'll ask how long it's been there and whether you've bitten that spot before. They may gently press the area to feel if it's soft, movable or fixed in place. This helps tell a mucocele or blocked duct apart from an irritation fibroma. If the lump comes with soreness, it also helps to mention why your cheek hurts in that area. 

How are these lumps treated? 

Treatment depends on what is causing the lump. Surgery is a common treatment for a confirmed mucocele, while freezing the tissue is another option.¹ The best choice may depend on the lump’s size, location and whether it keeps returning. 

An irritation fibroma may also be removed if needed. Your dental provider can check for a rough tooth, filling, denture or appliance that may be rubbing the area. A blocked saliva duct may need different care based on what is causing the blockage. 

Do not cut, squeeze or pop the lump yourself. This can injure the area and make it harder to heal. Your dental provider will explain which treatment is right for you. 

Can you prevent a lump from coming back? 

A few habits may lower your odds of a repeat lump: 

• Try not to chew or bite the same spot on purpose 

• Ask your dental provider to smooth a rough tooth or filling edge 

• Get a denture or retainer checked if it rubs your cheek or lip 

• Avoid picking at or popping a healing lump yourself 

Don't wait out a lump that keeps coming back in the same spot. Contact your local dental provider to have it checked, find out what's causing it and get a plan to help it stop returning. 

Why do I keep getting a soft lump inside my cheek or lip? FAQs 

Still have questions about a recurring soft lump inside your cheek or lip? These answers cover a few common concerns. 

Can a soft lump inside my cheek go away on its own? 

A mucocele may flatten after it breaks open, but the swelling can return. If the lump keeps coming back or remains for more than two weeks, ask a dental provider to examine it. 

When should I see a dental provider about a lump inside my cheek or lip? 

See a dental provider if the lump grows, feels hard, hurts, bleeds, changes color or lasts more than two weeks. You should also have it checked if the same spot keeps swelling. 

Can children get these lumps too? 

Yes. Mucoceles are often seen in kids, teens and younger adults. A dental provider can examine the spot and explain whether it needs treatment. 

Does a recurring lump mean I need surgery? 

Not always. Treatment depends on the cause of the lump. Surgery is commonly used for a confirmed mucocele, but other options may be available. 

Can teeth grinding or clenching cause a lump inside my cheek? 

Grinding or clenching may press your cheek against your teeth. This can lead to repeated biting or rubbing. If a lump keeps forming in the same place, a dental provider can check for irritation and other possible causes. 

Sources 

¹ American Academy of Pediatric Dentistry, Pediatric Dentistry: “Cryosurgery in the management of mucoceles in children.” https://www.aapd.org/globalassets/media/publications/archives/marcushamer2-19-04.pdf 

² American Association of Oral and Maxillofacial Surgeons: “Oral Lesion Evaluation, Biopsy Techniques and Referral Criteria for General Practitioners.” https://aaoms.org/wp-content/uploads/2024/03/oral_lesion_position_paper.pdf