Each teething episode typically lasts about 8 days: the 4 days before a tooth breaks through the gum, the day it emerges, and the 3 days after. That’s the window where your baby is most likely to be fussy, drooly, and uncomfortable. But because 20 baby teeth come in over roughly two years, teething can feel like a near-constant process even though each individual tooth causes only about a week of trouble.
The 8-Day Window
A prospective study tracking nearly 500 tooth eruptions found that teething symptoms were only significantly more frequent during an 8-day period centered around the day a tooth actually pokes through. Four days before eruption, symptoms ramp up. They peak on the day the tooth emerges, then taper off over the next three days. Outside that window, symptoms weren’t meaningfully different from a baby’s normal baseline.
This is useful to know because it sets realistic expectations. If your baby has been miserable for two or three weeks straight, something other than a single tooth is probably going on, whether that’s an illness, multiple teeth coming in back-to-back, or both at once.
Why It Hurts
A baby tooth doesn’t just slide up through the gum. It starts encased in jawbone. Specialized cells break down bone above the tooth to create a path, while new bone forms underneath to push the tooth upward. The only direction the tooth can go is out. Once it reaches the gum tissue, enzymes break down collagen fibers in the gum so the tooth can finally emerge. All of that remodeling creates pressure, swelling, and inflammation in the tissue, which is why your baby’s gums look puffy and feel tender before a tooth appears.
What Teething Actually Looks Like
The symptoms reliably linked to teething are all relatively mild and localized. Expect some combination of increased biting, drooling, gum rubbing, sucking, irritability, wakefulness, ear rubbing, facial rash (from all the drool), decreased appetite for solid foods, and a slight rise in temperature. No single symptom showed up in more than 35% of teething babies, so your child might get several of these or almost none.
Notably, true fever (100.4°F or higher), vomiting, diarrhea, cough, and body rashes were not significantly associated with tooth eruption. A teething baby’s temperature may tick up slightly, but it won’t hit the clinical threshold for fever. If your baby’s temperature reaches 100.4°F or above, that points to illness rather than teething. A temperature above 104°F warrants emergency care.
When Each Tooth Arrives
The first teeth to show up are usually the lower central incisors, the two bottom front teeth, between 6 and 10 months. From there, the schedule roughly follows this pattern:
- Upper central incisors: 8 to 12 months
- Upper lateral incisors: 9 to 13 months
- Lower lateral incisors: 10 to 16 months
- First molars: 13 to 19 months (upper), 14 to 18 months (lower)
- Canines: 16 to 23 months
- Second molars: 23 to 33 months
These ranges overlap considerably. That means your baby could have two or three teeth working their way through at the same time, which extends the period of fussiness and makes it feel like teething never ends. Molars tend to cause the most discomfort because of their larger surface area pushing through the gum.
Most children have all 20 primary teeth by around age 3. The entire process spans roughly two years, but the active symptomatic periods add up to a fraction of that time.
Easing the Discomfort
The American Academy of Pediatrics recommends keeping it simple. Gently rubbing or massaging your baby’s gums with a clean finger applies counter-pressure that can temporarily ease the aching. A firm rubber teething ring gives your baby something safe to chew on, which serves the same purpose.
A chilled (not frozen) teething ring adds mild cold to reduce gum swelling. Avoid freezing teethers, though. A rock-hard frozen ring can actually bruise tender gums and make things worse. Liquid-filled teethers are also worth skipping since they can break and leak.
The FDA has warned against topical numbing gels containing benzocaine for children under 2, and homeopathic teething tablets have also drawn safety concerns. For babies in significant discomfort, talk to your pediatrician about age-appropriate pain relief options rather than reaching for over-the-counter gels or tablets marketed for teething.
When Teeth Are Late
Some babies don’t get their first tooth until after their first birthday, and that’s usually fine. The eruption schedule varies widely from child to child. Genetics, birth weight, and whether a baby was born prematurely all influence timing. If your child still has no teeth by around 18 months, a pediatric dentist can evaluate whether there’s an underlying issue, but in most cases late teethers simply catch up on their own schedule.