Tooth Eruption Cyst
Content reviewed against published AAPD, AAP, NIH guidelines
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If your baby has been diagnosed with or you suspect tooth eruption cyst, here is what the evidence says.
The short answer
An eruption cyst is a fluid-filled, dome-shaped swelling that appears on the gum over a tooth that is about to erupt. It looks like a bluish-purple or translucent bump. Eruption cysts are benign and almost always resolve on their own when the tooth breaks through the gum. They are relatively common and do not require treatment in most cases.
Key takeaways
- An eruption cyst is a fluid-filled, dome-shaped swelling that appears on the gum over a tooth that is about to erupt. It looks like a bluish-purple or translucent bump. Eruption cysts are benign and almost always resolve on their own when the tooth breaks through the gum. They are relatively common and do not require treatment in most cases.
- Usually normal when: A bluish, fluid-filled bump appears on the gum where you expect a tooth to come in
- Call your doctor if: The area around the cyst becomes very red, warm, swollen, or is draining pus, which could indicate an infection
- Varies by age — see the age-by-age breakdown below
“Fever itself is not an illness — rather, it is a sign or symptom that the body is fighting an infection. Fever stimulates certain defenses, such as the white blood cells, which attack and destroy invading bacteria.”
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By Age
What to expect by age
0-3 months
Eruption cysts are rare at this age since most teeth have not begun to erupt. Bluish bumps on a newborn's gums are more likely Bohn's nodules, Epstein pearls, or gingival cysts, all of which are harmless and resolve on their own.
3-6 months
As the first teeth begin moving toward the surface, an eruption cyst may develop. It appears as a rounded, bluish or clear swelling on the gum ridge directly over where the tooth is erupting. The cyst is filled with fluid (or blood, making it appear darker). It is painless in most cases and resolves once the tooth erupts through it.
6-12 months
This is the most common age for eruption cysts since multiple teeth are actively erupting. The cyst may appear suddenly and can look alarming, but it is harmless. The tooth typically erupts through the cyst within 1-2 weeks. Parents should avoid popping or lancing the cyst at home as this could introduce infection.
12 months+
Eruption cysts can occur with any erupting tooth, including molars and canines. Molar eruption cysts may appear larger due to the tooth's size. If a cyst persists for several weeks without the tooth erupting, or if it appears infected, a pediatric dentist can perform a simple incision to expose the tooth.
What Should You Do?
When to take action
- A bluish, fluid-filled bump appears on the gum where you expect a tooth to come in
- The cyst is painless and your baby does not seem bothered by it
- The bump resolves on its own within 1-2 weeks as the tooth erupts
- Your baby continues to eat and feed normally despite the visible cyst
- The cyst has been present for more than 2-3 weeks without a tooth erupting through it
- The cyst appears to be growing significantly larger
- Your baby seems to have pain or discomfort from the cyst area
- The area around the cyst becomes very red, warm, swollen, or is draining pus, which could indicate an infection
- Your baby develops a fever along with gum swelling, or the bump is accompanied by significant facial swelling
Doctor Visit Checklist
Bring this checklist to your next pediatrician visit to discuss Tooth Eruption Cyst.
Things to mention
- The cyst has been present for more than 2-3 weeks without a tooth erupting through it
- The cyst appears to be growing significantly larger
- Your baby seems to have pain or discomfort from the cyst area
Observations to share
- The cyst has been present for more than 2-3 weeks without a tooth erupting through it
- The cyst appears to be growing significantly larger
- Your baby seems to have pain or discomfort from the cyst area
Urgent signs to report immediately
- The area around the cyst becomes very red, warm, swollen, or is draining pus, which could indicate an infection
- Your baby develops a fever along with gum swelling, or the bump is accompanied by significant facial swelling
My notes
From ismybabyalright.com — free, evidence-based baby health guides
Related Resources
Frequently asked questions
Is tooth eruption cyst normal?
When should I call the doctor about tooth eruption cyst?
When is tooth eruption cyst normal?
What causes tooth eruption cyst?
What should I mention to my pediatrician about tooth eruption cyst?
Is tooth eruption cyst normal at 0-3 months?
Is tooth eruption cyst normal at 3-6 months?
Should I go to the ER for tooth eruption cyst?
Does tooth eruption cyst go away on its own?
References
- [1]American Academy of Pediatric Dentistry. Guideline on Management of the Developing Dentition and Occlusion in Pediatric Dentistry. AAPD
- [2]American Academy of Pediatrics. Baby's First Tooth: 7 Facts Parents Should Know. HealthyChildren.org. AAP
- [3]National Library of Medicine. Eruption cysts: A series of two cases. Journal of the Indian Society of Pedodontics and Preventive Dentistry. NIH
All content follows our editorial policy and is reviewed against published clinical guidelines.
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Bottom line
Most cases of tooth eruption cyst are normal. Talk to your pediatrician if the area around the cyst becomes very red, warm, swollen, or is draining pus, which could indicate an infection.
Trust your instincts. If something feels wrong, reach out to your pediatrician. Worrying about your baby means you care — that is a good thing.
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