Upper front teeth typically come in one to two months after the lower front teeth. Most babies get their bottom central incisors between 5 and 8 months of age, followed by the upper central incisors between 6 and 10 months. The gap varies from baby to baby, and some children see both sets appear almost simultaneously.
The Typical Eruption Timeline
The lower central incisors are almost always the first teeth to break through, usually arriving between 5 and 8 months. The upper central incisors follow at 6 to 10 months. For an average baby, that means the top front teeth show up roughly one to two months after the bottom ones, though the overlap in those age ranges tells you just how much variation exists.
After those first four teeth, the pattern continues to alternate between upper and lower jaw. The upper lateral incisors (the teeth flanking the front two) tend to come in next at 8 to 12 months, followed by the lower lateral incisors at 7 to 10 months. By roughly 12 months, many babies have four to eight teeth total. The full set of 20 primary teeth is usually complete by age 2.5 to 3.
Full Eruption Sequence
A large study of primary tooth eruption confirmed this order from first to last:
- Lower central incisors (bottom front two)
- Upper central incisors (top front two)
- Upper lateral incisors (top sides)
- Lower lateral incisors (bottom sides)
- First molars (upper and lower)
- Canines (upper, then lower)
- Second molars (lower, then upper)
The lower jaw consistently leads the upper jaw for the central incisors and second molars, with statistically significant timing differences between the two jaws for those specific teeth. For the rest, the gap between upper and lower is less predictable.
Why the Bottom Teeth Come First
Lower front teeth tend to erupt earlier because the mandible (lower jaw) develops slightly ahead of the upper jaw during infancy. This is a consistent pattern across populations and studies. It doesn’t reflect anything about your baby’s health or nutrition. It’s simply how jaw development is sequenced.
Left and Right Teeth Don’t Always Match
Parents often notice that one bottom tooth appears days or even weeks before its partner on the other side. This is normal. Research on primary tooth emergence found that about 50% of matching tooth pairs erupt within 14 days of each other. In some cases, the gap between left and right was more than 50 days. There’s no strong genetic pattern to which side comes first, and a lopsided grin for a few weeks is nothing to worry about.
When Teeth Are Considered Delayed
The range of normal is wide. Some babies cut their first tooth at 4 months, others not until after their first birthday. Health professionals generally recommend an evaluation if your child has no teeth at all by 9 months. At that point, a provider will examine the gums and ask about family history, since late teething often runs in families. Dental X-rays are rarely needed, and in most cases, the teeth are simply on a slower schedule.
If your baby’s bottom teeth arrived on time but the top teeth seem slow to follow, give it at least two to three months before being concerned. The age ranges for upper and lower incisors overlap significantly, and a longer gap between the two is well within normal limits.
Caring for the First Teeth
As soon as that first bottom tooth breaks through, you should start brushing with fluoride toothpaste. Use a smear the size of a grain of rice on a soft infant toothbrush, twice a day, ideally after breakfast and before bed. This applies to every tooth as it appears, whether it’s on the top or bottom. At age 3, increase to a pea-sized amount of toothpaste.
Early teeth are vulnerable to decay from milk or formula pooling against them, especially overnight. Wiping the gums with a damp cloth before any teeth erupt helps establish the routine and keeps bacteria levels low so new teeth emerge into a cleaner environment.