Most 15-month-olds have between four and eight teeth, though anywhere from zero to twelve can be perfectly normal. Baby teeth follow a general timeline, but the actual number varies widely from child to child. Some babies cut their first tooth at four months, others not until after their first birthday, and both scenarios fall within the expected range.
The Typical Timeline for Baby Teeth
The two lower front teeth usually appear first, typically between six and ten months. The four upper front teeth follow, generally arriving between eight and twelve months. By 15 months, most toddlers have at least their front teeth in place, giving them that classic gappy grin with four to eight visible teeth.
Around this age, the first molars are also starting to push through. Upper first molars tend to emerge between 13 and 19 months, while lower first molars show up between 14 and 18 months. So your 15-month-old may be right in the middle of cutting molars, or those teeth may still be a few months away. Children eventually get 20 baby teeth total, but the full set doesn’t typically arrive until around age two and a half to three.
Why Some 15-Month-Olds Have Fewer Teeth
Genetics play the biggest role in when teeth appear. If you or your partner were late teethers, your child likely will be too. Premature birth can also shift the timeline, since tooth development follows biological age more closely than calendar age. Nutritional factors and certain medical conditions can contribute as well, but these are far less common causes.
If your child has no teeth at all by 15 months, that’s still not necessarily a red flag. The threshold that pediatric dentists use is 18 months. If your baby shows no signs of teething by that point, a dentist may recommend evaluation to rule out underlying issues. Before then, a tooth-free smile is usually just a matter of individual timing.
Signs Your Toddler Is Cutting Molars
Molar eruption tends to be more uncomfortable than front teeth because molars are larger and have a broad, flat surface that has to break through the gums. Common signs include increased drooling, red or swollen gums toward the back of the mouth, fussiness, irritability, difficulty sleeping, loss of appetite, and a strong urge to bite or chew on hard objects.
A slight rise in temperature can happen during teething, but a true fever above 100.4°F is not caused by teething. If your toddler develops a high fever, that points to something else, like an infection, rather than new teeth coming in.
Caring for Those First Teeth
Even a single tooth needs brushing. Use a child-sized toothbrush with a smear of fluoride toothpaste, roughly the size of a grain of rice. That tiny amount is the recommendation for all children under age three. You don’t need to increase to a pea-sized amount until your child is between three and six years old, and you’ll want to supervise brushing until they’re reliably spitting out the toothpaste rather than swallowing it, which for most kids is around age six or seven.
Before teeth appear, wiping your baby’s gums with a clean, damp washcloth after feedings helps keep bacteria in check. Once teeth are in, the biggest cavity risk for toddlers is prolonged exposure to sugary liquids. Bottles should contain only formula, breast milk, or milk, never juice or sugar water. Letting a toddler fall asleep with a bottle is one of the most common causes of early tooth decay, because the liquid pools around the teeth for hours. Transitioning to a cup around the first birthday helps reduce this risk.
Cavity-causing bacteria can also be passed from caregiver to child through shared saliva. Tasting food from the same spoon or cleaning a pacifier in your mouth can introduce bacteria into your toddler’s mouth before their natural defenses are ready for it.
When to Schedule a First Dental Visit
The American Academy of Pediatrics recommends seeing a dentist by your child’s first birthday or within six months of the first tooth appearing, whichever comes first. If your 15-month-old hasn’t been to a dentist yet, now is a good time to schedule that visit. The dentist can check that teeth are developing normally and may apply fluoride varnish, which is typically done two to four times per year depending on your child’s cavity risk.
These early visits are brief and low-key. They’re less about treatment and more about establishing a baseline, catching any issues early, and getting your child comfortable with the routine before they’re old enough to be anxious about it.