Brushing and flossing for kids by age

Reviewed by Dr. Samar Fadavi, DDS

Short answer: Start cleaning your baby's gums before the first tooth, brush twice a day as soon as teeth appear, and begin flossing when two teeth touch. Use a rice-grain smear of fluoride toothpaste under age 3 and a pea-sized amount from age 3. Parents should brush or check their child's teeth until about age 8, when most children can do a thorough job alone.

Why this guide

Parents in Scarborough and along the Danforth ask us the same questions again and again. When should we start brushing? How much toothpaste is safe? When do kids need floss? When can they brush on their own? The answers change as children grow, which is why we wrote this age-by-age guide.

Cavities are one of the most common health problems in childhood, and most of them can be prevented with steady habits at home and regular dental visits. This guide is general information for families. Your child's dentist can give advice for their own teeth and risk. To learn how we care for young patients, see our children's dentistry page.

Before the first tooth: birth to about 6 months

Good habits start even before teeth appear. Once a day, wipe your baby's gums with a clean, damp cloth or gauze wrapped around your finger, especially after the last feed of the day. This removes milk residue and gets your baby used to having the mouth cleaned.

• Do not put your baby to bed with a bottle of milk, formula or juice. Liquid pools around the teeth overnight and can cause early cavities once teeth arrive.
• Do not dip soothers in honey or anything sweet.
• Clean soothers with water, not by putting them in your own mouth, which can pass cavity-causing germs to your baby.

First teeth: about 6 months to 3 years

Most babies get their first tooth between 6 and 12 months, though some come earlier or later. As soon as a tooth appears, it needs brushing.

How to brush

1. Use a small, soft toothbrush made for babies.
2. Brush twice a day, morning and before bed.
3. Use a smear of fluoride toothpaste about the size of a grain of rice. Your dentist may adjust this based on your child's cavity risk.
4. Sit your child on your lap facing away from you, or lay them on a bed with their head in your lap, so you can see into the mouth.
5. Lift the lip to brush along the gum line, where cavities often start in young children.
6. Brush gently in small circles on every surface.

First dental visit

Dentists in Canada suggest a first visit within six months of the first tooth or by the first birthday. This early visit is short and gentle. It lets the dentist check the teeth, look for early signs of decay, and give you tips for your child's age. Our guide on your child's first dental visit explains what to expect and how to prepare.

Bottles, cups and snacks

• Begin moving from a bottle to an open cup around the first birthday.
• Give water between meals. Save milk for meals and keep juice small and occasional.
• Avoid sipping on milk or juice all day from a bottle or sippy cup.

Preschool years: 3 to 5

By age 3, most children have all 20 baby teeth. They want to do things themselves, which is a great time to build good habits, but they still need an adult to do the actual brushing.

Brushing

1. Move up to a pea-sized amount of fluoride toothpaste.
2. Let your child brush first, then take a turn yourself to finish the job.
3. Brush for two minutes. A song, a timer or a brushing app helps.
4. Teach your child to spit out the toothpaste, but they do not need to rinse with water afterward. Leaving a little fluoride on the teeth helps protect them.
5. Supervise so they do not swallow toothpaste or eat it from the tube.

Flossing starts here

Once two teeth touch each other, food can get trapped between them where a toothbrush cannot reach. For many children this happens between the back baby molars around age 2 to 3. Start flossing these spots once a day.

• Child-sized floss picks with a handle are easiest for parents.
• Slide the floss gently between the teeth, curve it against each tooth, and move it up and down.
• Bedtime is a good time, after brushing and before stories.

Our guide on fluoride in toothpaste explains why fluoride matters and how to use it safely.

Early school years: 6 to 8

This is the age of wiggly teeth and gaps. The first permanent molars, often called the six-year molars, come in behind the baby teeth without any baby tooth falling out first. Many parents do not notice them, yet they are among the most cavity-prone teeth in the mouth because of their deep grooves.

Brushing

• Children can take on more of the brushing, but most still need help or a check until about age 8.
• A good rule of thumb: if your child can tie their own shoelaces or write neatly, they may have the hand control to brush well on their own.
• Pay extra attention to the back molars. Have your child open wide so you can reach the very back teeth.
• Use a pea-sized amount of fluoride toothpaste.

Flossing

• Continue daily flossing, with your child doing more of it themselves using floss picks.
• Check that they reach the back teeth, not just the front.

Sealants

Ask your dentist about sealants on the new permanent molars. A sealant is a thin coating painted into the grooves of the chewing surfaces, which helps keep food and germs out.

Older children: 9 to 12

By now most children can brush and floss on their own. They still benefit from reminders and an occasional check, especially as baby teeth fall out and more permanent teeth come in.

• Brush twice a day for two minutes with fluoride toothpaste.
• Floss once a day. Regular string floss may now be easier than picks for some children.
• Look for plaque left behind at the gum line. Plaque-disclosing tablets from the pharmacy colour plaque so children can see what they missed.
• If your child plays hockey, basketball, soccer or martial arts, ask about a mouthguard.
• If braces or other appliances are part of the plan, cleaning becomes even more important.

Teenagers: 13 and up

Teens have busy schedules, irregular sleep and more snacks and drinks away from home. Brushing can slip. Energy drinks, sports drinks and pop are common sources of sugar and acid.

• Keep the routine: twice a day brushing and daily flossing.
• Encourage water over sweet or acidic drinks.
• Talk about the effects of vaping and smoking on gums and teeth.
• Keep up regular check-ups, even when they feel too busy.

Choosing a toothbrush and toothpaste

• Brush size: the head should be small enough to reach the back teeth comfortably.
• Bristles: always soft.
• Manual or electric: both work well when used properly. An electric brush can help children who rush or find brushing boring.
• Replace the brush every three to four months, or sooner if the bristles splay or after an illness.
• Toothpaste: choose a fluoride toothpaste. Flavour matters to children, so let them choose among fluoride options.

Making brushing fun

• Brush together as a family so children copy you.
• Use a two-minute song or timer.
• Let your child choose their own toothbrush colour or character.
• Use a sticker chart for younger children.
• Let them brush a stuffed animal's teeth first.
• Read picture books about visiting the dentist.
• Praise effort, not perfection.

Food, drinks and treats

How often children have sugar matters more than how much. Each sweet snack or drink starts an acid attack on the teeth that lasts for some time afterward.

• Offer sweet treats with meals instead of between meals.
• Make water the everyday drink.
• Choose tooth-friendly snacks such as cheese, vegetables, plain yogurt and fruit.
• Watch for sticky foods like gummies and dried fruit, which cling to teeth.
• After a treat, a drink of water helps rinse the mouth.

Holidays bring extra challenges. Our guide on Halloween candy and kids' teeth has practical ideas.

Steps for parents

1. Wipe your baby's gums daily before teeth appear.
2. Brush twice a day from the first tooth, with the right amount of fluoride toothpaste for age.
3. Start flossing when teeth touch.
4. Book the first dental visit by age one.
5. Help or check brushing until about age 8.
6. Keep sweet foods to mealtimes and water between meals.
7. Keep up regular dental check-ups.

What to avoid

• Bedtime bottles of milk, formula or juice.
• Too much toothpaste for young children.
• Letting young children brush alone without a check.
• Rinsing away all the fluoride with water after brushing.
• Sipping sweet drinks throughout the day.
• Waiting until there is pain before the first dental visit.

A brushing technique that works at any age

Whatever your child's age, the same simple method works well. Divide the mouth into four parts: top right, top left, bottom right and bottom left. Spend about 30 seconds on each part. Hold the brush at an angle toward the gum line and use small, gentle circles rather than hard scrubbing back and forth. Clean the outside of the teeth, then the inside, then the chewing surfaces. Finish by brushing the tongue lightly from back to front to freshen the breath.

Always follow the same order so nothing is missed. For young children, counting out loud or singing a short song for each part helps them stay still. Older children can use a two-minute timer with four short beeps, which many electric toothbrushes have built in. Pressing too hard is a common mistake. If the bristles splay out after a few weeks, your child is likely scrubbing too firmly.

Children with braces, appliances or extra needs

Children with braces, space maintainers or other appliances need extra time to clean around the wires and brackets. Small interdental brushes and floss threaders make this easier. A water flosser can help some children, though it does not fully replace floss.

Children with sensory sensitivities, autism, developmental differences or physical disabilities may find brushing very hard. Try a quiet room, the same routine every day, a soft or silicone brush, and a mild or unflavoured toothpaste. Visual schedules with pictures of each step help many children. Let the dental team know about your child's needs before the visit, so we can plan a calm appointment at a time of day that suits them.

When to see a dentist

Book a visit by your child's first birthday, and then as often as your dentist suggests. Call us sooner if you see white or brown spots on the teeth, bleeding gums, swelling, a chipped tooth, or if your child complains of tooth pain or avoids chewing on one side. Learn more on our children's dentistry page.

Frequently asked questions

Is fluoride toothpaste safe for babies?

Yes, in the right amount. A rice-grain smear is used under age 3 and a pea-sized amount from age 3. Supervise brushing so children do not swallow toothpaste.

My child hates brushing. What can I do?

Keep the routine calm and short, try different positions, brush together, and use songs or timers. Stay consistent; resistance usually fades.

When should children start flossing?

As soon as two teeth touch, often between the back baby molars around age 2 to 3.

Do baby teeth really matter if they fall out anyway?

Yes. Baby teeth help children chew, speak and hold space for adult teeth. Cavities in baby teeth can cause pain and infection.

Should my child use mouthwash?

Mouthwash is usually not needed for young children. Ask your dentist before using one, especially under age 6.

What are white spots on my child's teeth?

White chalky spots near the gum line can be an early sign of decay. Book a visit so the dentist can check them.

How do I brush a toddler who will not open their mouth?

Try the knee-to-knee position: sit facing another adult with your knees touching, lay your child back with their head in your lap, and brush quickly and gently. Calm and short works better than a struggle.

Is an electric toothbrush safe for young children?

Yes, from about age 3, with a child-sized head and an adult helping. Many children brush longer with one.