September 2026

How Long a Tooth Takes to Come In, Baby and Adult

By Your Health Magazine Health Information Team

Your baby has been drooling and chewing everything in sight, but days pass and no tooth appears. Or your child has lost a baby tooth, yet the adult tooth seems to be taking its time. So, how long does it take a tooth to come in? For a baby tooth, noticeable gum discomfort often lasts only a few days around the time the tooth breaks through. However, there is no reliable countdown from the first signs of teething to a visible tooth. Once any baby or permanent tooth appears, it may continue moving into its full position for weeks or months.

What Does It Mean for a Tooth to “Come In”?

Tooth eruption is a gradual process rather than a single event. A developing tooth moves through the jaw, approaches the gum and eventually becomes visible in the mouth. It then continues erupting until it reaches its functional position.

This distinction explains why the answer depends on what you are measuring. The tender period when a baby tooth breaks through the gum may be brief, but the complete eruption process takes considerably longer. Permanent teeth, especially molars, may continue moving toward their final biting position for many months after their first edges appear.

How Long Does It Take a Baby Tooth to Come In?

For one baby tooth, gum redness, tenderness or mild fussiness often occurs for a few days around the breakthrough. Some teeth emerge without causing any noticeable discomfort. Drooling and chewing are less useful as countdown signs because these behaviors may begin weeks or months before the first tooth appears.

Most babies develop their first tooth at approximately 6 months, although earlier or later eruption can be normal. The two lower front teeth usually come first. A typical schedule is:

Lower and upper front teeth: approximately 6 to 12 months
Lateral incisors beside the front teeth: approximately 9 to 16 months
First molars: approximately 13 to 19 months
Canines: approximately 16 to 23 months
Second molars: approximately 23 to 33 months

Most children have all 20 primary teeth by age 2 1/2 to 3. These ranges are guides, not deadlines. Genetics, growth and individual development can influence timing, and healthy siblings may follow noticeably different schedules.

Signs a Baby Tooth May Be Close

A tooth that is approaching the surface may create a firm bump or a pale area beneath the gum. Common teething-related changes include mild gum tenderness, increased chewing and drooling. A drool-related rash may also develop around the mouth.

Teething should not be assumed to cause a true fever, diarrhea, repeated vomiting or significant crying. These symptoms may point to an illness occurring at the same time. Learn more about the difference between normal teething changes and symptoms sometimes mistaken for teething fever.

How Long Does an Adult Tooth Take to Come In?

Permanent teeth begin appearing at about age 6. The first permanent molars often erupt behind the baby molars without replacing another tooth, while permanent front teeth push against the roots of primary teeth and help them loosen.

After a baby tooth falls out, the adult tooth may already be visible or may not appear for several weeks or months. The interval depends on the tooth’s position, available space and stage of development. A tooth that has just emerged will also need additional time to reach its full height and settle into the bite.

The usual permanent-tooth schedule includes:

First molars and lower central incisors: approximately ages 6 to 7
Upper central incisors and other lateral incisors: approximately ages 7 to 9
Canines and premolars: approximately ages 9 to 12
Second molars: approximately ages 11 to 13
Third molars, or wisdom teeth: commonly ages 17 to 21, when they develop and erupt

By the early teenage years, most children have 28 permanent teeth, excluding wisdom teeth. Wisdom teeth are highly variable: they may emerge later, remain trapped beneath the gum or never develop.

In everyday conversation, “adult tooth” can also mean a permanent tooth in a grown adult. If an adult permanent tooth is extracted or knocked out, another natural tooth will not grow in to replace it. Dental evaluation is important because replacement options and timing depend on the person’s oral health and the location of the missing tooth.

Why Might a Tooth Take Longer?

A slower tooth does not necessarily indicate a problem. Eruption commonly varies between children and even between the two sides of the same mouth. Possible reasons for a significant delay include:

A permanent tooth that is still developing or positioned farther from the gum
Insufficient space or crowding
A baby tooth that has not loosened normally
A tooth erupting in an unusual direction
An extra tooth blocking the expected path
A permanent tooth that never developed
Previous injury, infection or early loss of a baby tooth
Certain genetic, developmental or medical conditions

A dentist can examine the eruption pattern and determine whether dental X-rays are appropriate. X-rays may show whether the permanent tooth is present, how it is positioned and whether something is blocking it.

Helping During the Eruption Process

For a teething baby, gently massaging the gum with a clean finger or offering a chilled, firm rubber teether may provide comfort. Do not give a baby an object that is frozen solid, and avoid amber necklaces because they pose choking and strangulation risks. Numbing products containing benzocaine or lidocaine can be dangerous for young children. Ask a pediatrician or pediatric dentist before using pain medicine.

Begin brushing as soon as the first tooth appears. Use a soft, child-sized toothbrush and a smear of fluoride toothpaste about the size of a grain of rice for children younger than 3. Brush twice daily, including after the final food or drink at night. A child’s first dental visit should occur when the first tooth erupts or by the first birthday.

For additional general health education, readers can explore trusted health topics from MedlinePlus.

When to Seek Care

Mention the absence of teeth to a pediatrician or dentist if no baby tooth has appeared by approximately 9 to 12 months, especially when there are other growth or developmental concerns. Delayed eruption is often a normal variation, but an examination can provide reassurance and identify uncommon causes.

Schedule a dental evaluation if a permanent tooth shows no progress for several months after a baby tooth falls out, one side erupts much earlier than the matching side, a tooth appears trapped or out of position, or a retained baby tooth interferes with an emerging permanent tooth. A pediatric dentist or general dentist can assess the area and may recommend an orthodontist when crowding or alignment is involved.

Seek prompt care for severe or worsening pain, pus, facial swelling, uncontrolled bleeding or signs of dental infection. Trouble breathing or swallowing requires emergency attention. Babies with a true fever, persistent diarrhea, vomiting, unusual sleepiness or substantial feeding difficulty should be evaluated by a pediatrician rather than having those symptoms attributed to teething.