Think twice before handing that sippy cup to your 2-year-old. According to the American Academy of Pediatrics (AAP), he should have moved on to a regular cup around his first birthday. (Same thing goes for giving up his bottle.)

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Lots of parents aren't aware of this advice. If you're one of them, here's why you should help your toddler ditch the sippy cup asap.

1. If he falls with it in his mouth, he could get hurt. In the United States, a tot winds up in the emergency room every four hours for injuries related to sippy cups, bottles and binkies (pacifiers). This usually happens when the child falls and cuts his mouth or chips a tooth. A 2012 study in the journal Pediatrics found that over a period of 19 years, 45,398 kids under age 3 were treated in emergency rooms for such injuries. That’s nearly 2,300 children a year.

2. Sippy cup-related falls can damage teeth. For this reason, dentists also discourage the use of sippy cups and bottles beyond age 1, says Aaron Stump, DDS, with Charlottesville Pediatric Dentistry in Virginia.

3. Keeping a sippy cup in his mouth all the time can harm a toddler's health. Over time, sucking on the rigid plastic of a sippy cup can alter the natural shape of a child's mouth, which can affect his speech, quality of sleep and breathing, according to Stump.

4. Sucking on a sippy cup for long periods can ruin a child's pearly whites. If your little one is sipping juice from a cup throughout the day, the constant flood of sugary liquid over his teeth can lead to decay and cavities. Even cavities in baby teeth can set the stage for a lifetime of dental problems, warn dentists.

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Safe sipping

If your child is still using a sippy cup (because he's not a year old or because you haven't yet weaned him from it), keep these tips in mind until he's made the switch to a regular cup.

Keep an eye on him. “Don’t let your toddler drink from a sippy cup without supervision,” Stump says. Insist he stay seated until it's empty. After all, if he's not running around with the cup in his mouth, he can't fall down with the cup in his mouth.

Fill sippy cups with water between meals . Stump advises limiting juice to mealtimes, especially if you allow your child to have a sippy cup throughout the day. In that case, it should be filled with water, says Stump. Don't let him take a sippy cup or bottle to bed, he adds.

Make a dental appointment for your child after his first birthday . This way, the dentist can check to make sure his teeth are developing properly.

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Steve Evans, MA, is an award-winning journalist with more than 20 years experience in daily news, investigative, health and business journalism. Among other jobs, he has served as managing editor of the Central Virginia Newspaper Group, as a senior writer for SNL Financial and as a staff writer for The Progress Index and the Richmond Times-Dispatch.