Tooth Eruption In Louisville, CO

Most babies get their first tooth between 5 and 10 months, and the 2 national charts that define normal do not agree with each other. That is usually the answer to why your child looks months behind the baby at daycare.

Below: both charts, the 4 signs that actually mean call a dentist, what teething does and does not cause, and what changes when the permanent molars arrive at 6.

The 2 National Charts Disagree, and That Is Why Your Child Is Probably Fine

The American Dental Association and the American Academy of Pediatric Dentistry both publish primary eruption charts. They give different ranges for the same tooth. Neither is wrong. The AAPD's numbers, from its Dental Growth and Development reference, run 2 to 3 months earlier than the ADA's across the whole set.

Three examples, and the first is the starkest:

For the lower lateral incisor the ADA says 10 to 16 months and the AAPD says 7 to 10. Those 2 ranges share exactly one month and no other. A 9-month-old with a lower lateral incisor is early by one chart and normal by the other.
For the upper second molar it is 25 to 33 months against 20 to 30. Put them together and the last baby teeth carry a 13-month window.
Even the first tooth most parents watch for splits the 2 charts. Lower central incisors are 6 to 10 months on one and 5 to 8 on the other.

Primary teeth begin calcifying in the 4th fetal month. The teeth were forming before your baby was born, which is part of why the timing scatters so much. Eruption was never a due date.

The arrival order, using both charts

Below is the sequence a Louisville toddler actually follows, with the widest published window for each tooth. Each range spans both the ADA and the AAPD figures, so if your child falls anywhere inside it, at least one national chart calls that normal.

Lower central incisors, 5 to 10 months
Upper central incisors, 6 to 12 months
Lower lateral incisors, 7 to 16 months
Upper lateral incisors, 8 to 13 months
Lower first molars, 11 to 18 months
Upper first molars, 11 to 19 months
Upper canines, 16 to 22 months
Lower canines, 16 to 23 months
Lower second molars, 20 to 31 months
Upper second molars, 20 to 33 months

Notice where the lower lateral incisors sit. On the ADA chart they arrive after the upper laterals; on the AAPD chart they arrive before. The order itself is not fixed, which is the second reason a chart cannot tell you your child is behind.

When Baby Teeth Fall Out, and Why the Dates Matter

Every one of the 20 primary teeth has a departure date as well as an arrival window. Most charts online print the arrivals and stop. Several skip the canines entirely, which is the exact stretch where a toddler is most miserable.

Here is when each set leaves, in the order it happens, per the American Dental Association:

Central incisors, upper and lower, 6 to 7 years
Lateral incisors, upper and lower, 7 to 8 years
First molars, upper and lower, 9 to 11 years
Lower canines, 9 to 12 years
Upper canines, 10 to 12 years
Second molars, upper and lower, 10 to 12 years

Those dates are a diagnostic tool, not trivia. A 6-year-old losing a bottom front tooth is on schedule. A 4-year-old losing one is not, and that is a same-week call, because a baby tooth lost that early usually means trauma or decay rather than development.

The gap between arrival and departure is the whole reason baby teeth get looked after. A lower central incisor is in the mouth for about 6 years and a second molar for close to a decade, which is long enough for a cavity to cost your child a tooth they still need.

Newly erupted enamel is still mineralizing, which is why the first years are when fluoride exposure matters most. Louisville city water already sits at the federal target, so for most households here the answer is toothpaste and in-office varnish rather than drops. Wells, reverse osmosis and bottled water change that. The full version is on our page about fluoride and your tap water.

When Late Is Actually Late

Almost every worried parent who calls us is describing normal scatter. These 4 are the ones that change the answer.

No teeth at all by 12 months

Raise it at the age-1 visit. Plenty of healthy children are still empty at a year and need nothing but a follow-up date. This is a mention, not an appointment on its own.

One side more than 6 months behind the other

Asymmetry is a better reason to book than lateness. A whole mouth running late is usually timing. One side running late points at something local, and something local has a cause worth finding.

No teeth at all by 18 months

Book an evaluation. An x-ray is not automatic and depends on what the exam and the family history show. What we confirm is that the teeth are present and on their way.

Any single tooth more than 2 years past its window

At that point obstruction and the rarer eruption failures enter the conversation, and both are easier to manage before the neighbouring teeth close the space.

Your pediatrician saying "it will come" and a pediatric dentist saying "let us look" answer 2 different questions. The first is about your child's growth and it is usually right. The second is about whether the tooth exists, where it is sitting, and whether anything is in its path. Only one of those is answerable from a chart.

What Teething Does, and What It Does Not

The symptoms that hold up

A meta-analysis of 16 studies in Pediatrics found symptoms in about 70% of children during eruption. Gum irritation 86.8%, irritability 68.2%, drooling 55.7%. Add biting and gum swelling and that is the list. Symptoms cluster in roughly an 8-day window around each tooth, then stop.

Fever, and why the number is 100.4

The American Academy of Pediatrics defines a fever as a rectal temperature of 100.4°F (38°C) or higher. Teething can nudge a baby's temperature slightly, inside the normal range. It does not cross 100.4.

If your baby is 3 months or younger and has a rectal temperature of 100.4°F or higher, call your pediatrician immediately. Not in the morning, and not after seeing whether a tooth appears.

At any age, 100.4 or above, diarrhea, vomiting or a rash means something other than teething. Plenty of dental websites still print 101°F. The number is 100.4.

Night waking, and the 2025 study that changed the answer

Night waking is on every teething list you have read. In 2025 it came off ours.

Researchers followed 849 infants aged 3 to 18 months across the US and Canada, scoring sleep from video baby monitors against the date each tooth broke through. On teething nights, total sleep time, night wakings and parent visits to the crib all held steady. In the same study, 55.3% of parents reported less sleep and 87.4% reported more wakings. Kahn M, et al. Journal of Pediatrics, 2025.

The gap between those 2 results is the finding, and the authors published it to prevent overuse of pain medicine and numbing gels. So when the nights fall apart for a fortnight, check illness, a schedule change or a sleep habit before reaching for anything.

What Helps, and What to Throw Out

What works

A clean, chilled teether. Firm rubber, not liquid filled, cold from the refrigerator. Not from the freezer. The FDA's instruction: "Make sure the teething ring is not frozen. If the object is too hard, it can hurt the child's gums."

Counter-pressure. A clean finger or damp gauze, rubbed firmly along the gum. At 2 in the morning it is the most useful thing available to you, and it costs nothing.

A cold, damp washcloth. Most babies chew one longer than they will hold a teether.

Acetaminophen or ibuprofen at the dose your pediatrician gives you, for a night nobody is getting through. Age limits apply to ibuprofen. Ask first.

Wipe the gums after feedings even before any teeth appear, and start brushing the day the first tooth arrives. Rice-grain smear of fluoride toothpaste until 3, pea-sized after. Floss once any 2 teeth touch.

What the FDA warns against

Benzocaine gels, meaning Baby Orajel, Anbesol, Cepacol and similar. The FDA states these "should not be used for teething pain in children because they can be dangerous," and that using them "can lead to a serious, and sometimes fatal, condition called methemoglobinemia, in which the oxygen-carrying capacity of red blood cells is greatly reduced." In 2018 the agency moved to take them off the market for teething.

Viscous lidocaine. The FDA says the prescription oral solution "also should not be used to treat teething pain in infants and young children," and that it "can cause grave harm, such as heart problems, severe brain injury and even death."

Teething jewelry, including amber necklaces. The FDA reports "death and serious injuries to infants and children, including strangulation and choking, caused by teething jewelry." The AAP does not recommend that infants wear any jewelry.

Homeopathic teething tablets. The FDA names these among teething products that can be dangerous to children.

Source: FDA, Safely Soothing Teething Pain in Infants and Children. If any of these are in the house, throw them out.

Facial swelling, a fever that will not come down, or a child who will not drink is an emergency, not teething.

At 6, the Job Changes

The first permanent molars arrive around age 6. They do not replace a baby tooth. They erupt behind the last one, in a spot most parents never look at, and they are the teeth most likely to be carrying decay by third grade.

Colorado's third-grade numbers

The Colorado Basic Screening Survey for 2022-23 screened 2,773 children across 42 elementary schools. 60.6% of third-graders already had caries experience, up from 46.2% in kindergarten. A quarter had untreated decay at screening. Only 57.1% had sealants.

Sealants go on those molars in the year they arrive, not the year someone notices a problem. In a state where 3 in 5 third-graders already have a decay history, that year is a deadline, and it is what the cleanings and exams at 6 and 7 are for.

When a 6-year molar gets stuck

Sometimes the new molar erupts at an angle and wedges under the back baby tooth instead of coming up beside it. It is called ectopic eruption and it shows up in 0.75% to 6% of children.

Most of it fixes itself: about 66% self-correct before age 7 and closer to 71% by age 9, so the standard plan is to watch for 3 to 6 months. The calendar is what changes the plan. A molar still locked at 7 or 8 is much more likely to be permanently stuck.

If it does not free itself the sequence is predictable. The baby molar gets damaged and comes out early, the space behind it collapses, and the premolar underneath gets trapped. That is a crowding and spacing problem built out of one tooth nobody watched. It shows on an exam and an x-ray and is silent otherwise, which is the whole argument for a checkup that year.

About Dr. Alison Grover

Dr. Alison Grover is a Board-Certified Diplomate Pediatric Dentist and the owner of Mini Miners. She earned her DDS and a General Practice Residency certificate at the University of Colorado School of Dental Medicine, then completed a two-year pediatric residency and a Pediatric Dental Certificate at UCLA. As a Diplomate she has passed the written and oral examinations of the American Board of Pediatric Dentistry. She also holds a degree from Wellesley College, with a background in child psychology that shows in how a frightened 2-year-old gets handled.

She grew up in Boulder County and went to Fairview High School. In 2017 she and her husband designed and built Mini Miners from the ground up.

A board-certified pediatric specialist completes additional years of residency after dental school, specifically in infants, children, adolescents and patients with special health care needs. A general dentist who sees children has not. More about the practice on our pediatric dentist in Louisville page.

Book an Eruption Check

Two visits pay for themselves: the one after the first tooth, and the one in the year the permanent molars arrive. Both are quick, and both catch things that are invisible from the outside.

We work with all major private insurance carriers, and we offer a membership plan for families without dental coverage.

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Tooth Eruption FAQs

My baby has no teeth at 12 months. Should I worry?

Probably not, and it is worth raising at the age-1 visit. Eruption timing scatters widely and a late first tooth is usually nothing. The threshold that prompts an evaluation is 18 months with no teeth at all. An x-ray is not automatic and depends on the exam.

Can teething cause a fever?

No. The American Academy of Pediatrics defines a fever as a rectal temperature of 100.4°F (38°C) or higher and states that teething does not cause a true fever. Anything at or above 100.4 is something else. If your baby is 3 months or younger with a rectal temperature of 100.4 or higher, call your pediatrician immediately.

Does teething keep babies awake at night?

The measured answer is no. A 2025 study in the Journal of Pediatrics followed 849 infants aged 3 to 18 months with video-based sleep scoring and found no change in total sleep, night wakings or parent visits to the crib on teething nights, while 55.3% of parents reported less sleep and 87.4% reported more wakings. If nights have fallen apart for 2 weeks, illness, a schedule change or a sleep habit is more likely than a tooth.

Is Orajel safe for my teething baby?

No. The FDA states that benzocaine products including Orajel should not be used for teething pain in children because they can cause methemoglobinemia, a serious and sometimes fatal condition that reduces the blood's ability to carry oxygen. Prescription viscous lidocaine carries a separate FDA warning against use for infant teething. Use a chilled firm teether and gum pressure instead.

My child's permanent tooth is coming in behind the baby tooth. Is that normal?

Yes. It is common between 5 and 7 and it is often called shark teeth. Watch it for 2 months. In most cases the baby tooth loosens and comes out on its own as the permanent tooth moves forward. If the baby tooth is still solid after 2 months, or your child cannot chew on that side, call us. It is usually a one-visit extraction.