Babies start teething at about 6 months old. The first tooth usually appears between 4 and 7 months, and the timing varies from child to child.
Key facts:
- Teething start: about 6 months, according to the American Dental Association
- First tooth: usually between 4 and 7 months, according to the American Academy of Pediatrics
- Timing: differs by months between healthy babies
What Is Teething?
Teething is the process in which a baby’s first teeth push through the gums. The medical term is tooth eruption.
Babies usually have 20 baby teeth at birth, according to the American Dental Association. Teething is the stage when those teeth rise through the gums one at a time.
The gums around a new tooth swell and feel tender. Most parents notice drooling and chewing first, and signs of teething in babies include each sign in detail.
At What Age Do Babies Start Teething?
Four reference ages describe when teething starts:
- The American Dental Association states that baby teeth begin to come in at about 6 months of age.
- The American Academy of Pediatrics gives a typical range of 4 to 7 months for the first tooth.
- The ADA chart lists the lower central incisor, usually the first tooth, at 6 to 10 months.
- The American Academy of Pediatrics also states that most babies develop teeth between 6 and 12 months, and that some babies have no teeth by their first birthday.
The ages differ because they measure different things. The first two describe when teething begins in general. The third describes one specific tooth. The fourth covers the first teeth to appear across most babies. The wider ranges reflect how much timing differs between healthy babies.
A Japanese birth cohort study of 1,690 children, published in the journal Children in 2023, measured that spread for the lower central incisor. The median age was 7.1 months for boys and 7.6 months for girls, and 80 percent of babies fell between about 4 and 11 months. Parents recorded the tooth earlier than dental check-ups did, which is one reason published ages differ. The study covers children in Japan, so these are reference points, and timing can differ between countries.
The lower central incisors, the two bottom front teeth, usually come in first. The order for all 20 teeth is in the baby teeth eruption chart.
Why Do Some Babies Start Teething Earlier or Later?
Eruption timing varies between healthy babies, and 3 factors may influence it, heredity, premature birth, and sex:
- Heredity: The American Academy of Pediatrics states that teething timing may be influenced by heredity.
- Premature birth: studies differ. A 1988 study in Pediatric Dentistry, the journal of the American Academy of Pediatric Dentistry, found later tooth eruption in very low birth weight babies, those born under 1,500 grams (about 3.3 pounds). The 2023 Japanese cohort found no difference by calendar age between preterm and full-term babies, and earlier eruption when age was corrected for prematurity.
- Sex: in the same Japanese cohort, boys’ lower central incisors appeared about 2 weeks earlier than girls’.
Even healthy babies differ by months. The ADA chart gives the first tooth a 4-month window, 6 to 10 months.
The American Academy of Pediatrics states that a later first tooth does not mean anything is wrong, and notes that some babies have no teeth by their first birthday. A pediatric dentist can check a baby’s gums during routine check-ups and cleanings.
Is Teething a Reason to See a Pediatric Dentist?
No, teething timing alone is not a reason for concern, according to the American Academy of Pediatrics. The first dental visit follows the first tooth, and when a child should first see the dentist explains the timing.
Kids Choice Pediatric Dentistry is a board-certified pediatric dental practice in Las Vegas that welcomes babies from 6 months old.
FAQs About When Babies Start Teething
How early can a baby start teething?
Most babies start teething between 4 and 7 months, according to the American Academy of Pediatrics. In a Japanese cohort of 1,690 children, about 1 in 10 babies had the lower front tooth by 4.1 months. Teething age alone does not mean anything is wrong.
Does a late first tooth mean something is wrong?
A later first tooth does not mean anything is wrong, according to the American Academy of Pediatrics. Some babies have no teeth by their first birthday. In a Japanese cohort, 9 in 10 babies had the lower front tooth by about 11 months. A pediatric dentist can check the gums at any visit.
Do boys start teething earlier than girls?
Slightly. A Japanese birth cohort study of 1,690 children found the lower central incisor appeared at a median of 7.1 months in boys and 7.6 months in girls, a gap of about 2 weeks. The difference is small next to the months that healthy babies vary by.
Do premature babies start teething later?
Sometimes, and studies differ. A 1988 study in Pediatric Dentistry found later tooth eruption in very low birth weight babies, those born under 1,500 grams. A 2023 Japanese study found no difference by calendar age, and earlier eruption by corrected age. A pediatric dentist can review a premature baby’s timing.
Kids Choice Pediatric Dentistry welcomes babies from 6 months old. Book online at any time, with new patient appointments usually available within 1 week.