Start cleaning your child’s mouth before they even have teeth. From birth, you can gently wipe your baby’s gums with a clean, damp washcloth or piece of gauze after each feeding. This removes bacteria and bits of food, and it gets your baby used to having their mouth cleaned. Once the first tooth appears (usually around six months), it’s time to switch to a toothbrush and begin brushing twice a day.
What to Use at Each Age
For babies and toddlers under three, use a child-sized toothbrush with soft bristles and a rice-grain-sized smear of fluoride toothpaste. Soft bristles are gentle on gums while still effective against plaque and food debris. Medium or hard bristles can hurt delicate gum tissue and make a child want to avoid brushing altogether.
At age three, increase the toothpaste to a pea-sized amount. The child’s toothbrush should fit comfortably in their hand and mouth. An adult toothbrush is too large for a small child to control or maneuver around their teeth. A non-slip grip helps if your child tends to drop things. Look for toothbrushes with the ADA Seal of Acceptance, which confirms they meet safety and effectiveness standards.
The Brushing Technique Step by Step
The method recommended by the Children’s Hospital of Philadelphia works for any age once teeth are present:
- Angle the brush at 45 degrees against the gumline where the tooth meets the gum.
- Use small circular motions on just a few teeth at a time, working your way around the entire mouth.
- Cover all three surfaces: the outside (cheek side), the inside (tongue side), and the flat chewing surfaces on top.
- Brush the tongue gently to clear bacteria and freshen breath.
For children three and older, aim for two full minutes per session. A timer, a two-minute song, or a brushing app can help kids stay on track. Children under three don’t need a strict two-minute rule, but you should still brush thoroughly enough to cover every tooth surface morning and night.
Why Bedtime Brushing Matters Most
Both brushing sessions are important, but the one before bed is critical. During sleep, saliva flow drops significantly. Saliva is your child’s natural defense system: it washes away food particles and helps repair early damage to tooth enamel caused by acid. With less saliva flowing overnight, any sugar or starch left on the teeth gives bacteria hours of uninterrupted time to produce acid and wear down enamel. Make sure your child doesn’t eat or drink anything with sugar after their bedtime brushing.
Spit, Don’t Rinse
After brushing, teach your child to spit out the excess toothpaste rather than rinsing with water. Rinsing washes away the fluoride that the toothpaste leaves behind on the teeth. That residual fluoride continues to strengthen enamel and fight cavities after brushing is done. Research on fluoride toothpaste effectiveness shows that not rinsing, or rinsing minimally, provides greater cavity protection than swishing with a full mouthful of water. Spitting is fine, but skipping the rinse makes a real difference.
When to Start Flossing
Begin cleaning between your child’s teeth as soon as two teeth touch each other. For many kids, this happens with the baby molars. A toothbrush can’t reach the tight spaces where teeth press together, and that’s exactly where cavities like to form. You can use traditional floss, child-sized floss picks, or interdental brushes, whichever is easiest for you and your child. Keep it up daily.
How Long You Should Do the Brushing
Most children don’t have the hand coordination to brush effectively on their own until around age six to eight. Until then, you should be the one holding the brush and doing the actual cleaning. A common approach is to let your child “practice” brushing first, then you follow up and do a thorough job. This gives them a sense of independence while making sure every surface actually gets cleaned.
Even after kids start brushing independently, supervise them. Watch for common shortcuts: skipping the tongue side of the teeth, avoiding the back molars, or brushing for only 20 seconds. Standing in the bathroom with them until they’ve built a reliable habit is one of the most effective things you can do for their long-term dental health.
Getting a Resistant Child to Brush
Toddlers and preschoolers who clamp their mouths shut or cry during brushing are incredibly common. Forcing the issue with a stern approach tends to backfire, creating a negative association that makes the next session even harder. Research on parenting strategies and oral health consistently finds that positive reinforcement, meaning encouragement and specific praise, leads to better brushing habits and fewer cavities over time.
A few strategies that work:
- Build a predictable routine. Brushing happens at the same time, in the same place, every day. When it’s simply what happens after bath time, there’s less room for negotiation.
- Give specific praise. Instead of a generic “good job,” try “You opened your mouth so wide, that really helped me get those back teeth.” This reinforces the exact behavior you want repeated.
- Offer limited choices. Let your child pick between two toothbrush colors or two toothpaste flavors. Having some control over the process reduces resistance.
- Make it social. Brush your own teeth at the same time. Kids imitate what they see, and brushing together normalizes the routine.
- Set clear, simple boundaries. “We brush our teeth every night before stories” is a ground rule, not a negotiation. Keep your tone warm but consistent.
If brushing has become a battle, start by noticing what is going well. Maybe your child lets you brush the front teeth but resists the back ones. Build from there. Focus on expanding what’s already working rather than highlighting what’s going wrong. Parents who approach the situation with empathy and patience see better results than those who rely on pressure or threats.
Quick Reference by Age
- Birth to first tooth: Wipe gums with a damp washcloth or gauze after feedings.
- First tooth to age 3: Brush twice daily with a soft-bristled child’s toothbrush and a rice-grain smear of fluoride toothpaste. Parent does the brushing.
- Ages 3 to 5: Brush twice daily for two minutes with a pea-sized amount of fluoride toothpaste. Parent still does the brushing or closely assists.
- Ages 6 to 8: Child can begin brushing independently with supervision. Parent checks for missed spots and follows up as needed.