Your child's dental health begins before their first tooth erupts. The decisions made in the first few years — when to start brushing, when to see a dentist, how to handle thumb sucking or pacifiers, what to do about cavities in baby teeth — have real consequences for their long-term oral health. This guide answers the most common questions parents have.
The most important thing to know: Baby teeth matter. Even though they fall out, cavities in primary teeth cause pain, can spread to developing permanent teeth, and affect a child's ability to eat, speak, and develop normally. Treating them is always worth it.
When do baby teeth come in?
Most children begin teething around 6 months of age, though anywhere from 4 to 12 months is within the normal range. By age 3, most children have all 20 primary (baby) teeth. Permanent teeth begin replacing primary teeth around age 6, and most children have their full set of permanent teeth (except wisdom teeth) by age 12 to 13.
6–12 months
Lower and upper central incisors (front teeth) typically erupt first.
1–2 years
Lateral incisors, first molars, and canines complete. Most of the 20 primary teeth are in.
2–3 years
Second primary molars erupt. Full set of 20 baby teeth complete by age 3.
When to schedule the first dental visit
The American Academy of Pediatric Dentistry recommends a child's first dental visit by age 1 — or within 6 months of the first tooth erupting. Many parents wait until age 3 or 4, which means cavities and early problems go undetected for years.
The first visit is low-key — the dentist checks tooth development, looks for early signs of decay, discusses diet and brushing, and gets the child comfortable in the dental environment. Starting early builds familiarity and reduces dental anxiety significantly.
When and how to brush
Before teeth erupt
Wipe the gums with a clean, damp cloth after feedings. This removes bacterial buildup and gets the child used to mouth cleaning before teeth arrive.
First tooth through age 3
Brush twice daily with a soft infant toothbrush and a smear of fluoride toothpaste — about the size of a grain of rice. Yes, fluoride toothpaste from the very first tooth. The amount is tiny and the benefit is significant.
Ages 3 to 6
Increase to a pea-sized amount of fluoride toothpaste. Supervise brushing closely — children under 6 don't have the dexterity to brush effectively on their own. You should be doing the brushing or finishing after they try.
Ages 6 and up
Children can begin brushing more independently but should still be supervised and their technique checked regularly until around age 8 to 10.
Cavities in baby teeth — do they need treatment?
Yes — always. This is one of the most common misconceptions in pediatric dentistry. Parents often ask why they should fill a cavity in a tooth that will fall out anyway. The reasons are clear:
- Untreated cavities cause pain that affects eating, sleeping, and concentration at school
- Infected baby teeth can spread bacteria to developing permanent teeth directly below them
- Baby teeth hold space in the jaw for permanent teeth — losing them early causes permanent teeth to drift and erupt in wrong positions
- Chronic dental pain affects speech development, nutrition, and overall quality of life
Thumb sucking, pacifiers, and bottle feeding
Pacifiers and thumb sucking
Both are normal comfort behaviors in infancy and early toddlerhood. The concern arises when they continue past age 3 to 4 — at this point, persistent sucking habits can affect the development of the bite and the shape of the roof of the mouth. Most children stop on their own before this becomes a problem. If the habit continues past age 4, discuss options with your dentist or pediatrician.
Bottle feeding and nursing
Putting a child to bed with a bottle of milk, formula, or juice exposes their teeth to sugar throughout the night — a pattern that causes "baby bottle tooth decay," which can devastate the front teeth. Always clean the teeth after the last feeding of the night. Transitioning off the bottle by age 12 to 18 months significantly reduces this risk.
Dental sealants — what they are and when they're recommended
Dental sealants are thin plastic coatings applied to the grooves of back molars — the areas most prone to cavities because toothbrush bristles can't reach the deep pits effectively. They are typically applied to permanent first molars when they erupt around age 6, and second molars around age 12. They're painless, quick, and reduce cavity risk in these teeth by up to 80%.
The bottom line
The habits established in childhood determine the foundation of lifelong oral health. Starting dental care early, brushing with fluoride toothpaste from the first tooth, and treating cavities in primary teeth — even baby teeth — are not optional. A child who grows up comfortable with the dentist, free of untreated cavities, and with good brushing habits is set up for a lifetime of better dental health.