Duff helped the nonprofit fete the milestone by lending her endearing grin and spreading the message about the importance of oral health for kids.
Smiles Across America launched the initiative in 2004 to provide oral disease prevention services for children who are uninsured and underserved due to issues of poverty, such as lack of resources, transportation barriers, low literacy and language diversity.
"They've raised over $2 million with this initiative and they help over 400,000 kids a year. I think spreading awareness — getting kids educated and getting them the care that they need — is really important," she said.
She was, likewise, impressed by how easy Trident made it for the public to get involved.
"If you buy a pack of Trident gum this week, 5 cents gets donated to Smiles Across America. They're going to raise $200,000 in a week, so those are big numbers and really exciting. A lot of good can be done with that."
Joining the cause was a bit of a no-brainer for Duff, who admits she's "a big gum chewer," specifically of Trident products. And, admittedly, she has a little extra motivation in the incredibly cute form of 2-and-a-half year-old son, Luca.
"Now that I have a 2-year-old, I just got inspired and wanted to get involved," she said.
Fortunately for Duff, Luca seems to be taking her early oral health care message to heart. "I have to be totally honest with you, and I'm going to sound like the annoying parent who thinks their kid's perfect," she said. "He's 2-and-a-half and I swear we've never had trouble with him brushing his teeth."
Still, he is a toddler and a toddler boy at that, so Duff admits Luca requires a little extra incentive from time to time.
"When we have trouble with him, we always like to give him a challenge. Like, 'Oh, I bet you can't brush your teeth standing on one foot!' So, he's like, 'I can, I can, I can!'"
Duff also relies on fun methods, like using a toothbrush timer, singing Raffi songs and letting Luca pick his own toothpaste and favorite toothbrush (Lightning McQueen).
Most importantly, though, she says, she leads by example. "If you're just sitting there telling them to do it, but you're not doing it when them, then they're like, 'Well, you're not doing it, so why would I?'"
Duff knows all too well the havoc poor health care can have on a child's self-esteem.
"I work with so many other children's organizations and charities and I can't tell you the amount of times a kid won't smile at me because of their teeth, and that should never be the case," she said.
Duff has long been vocal about her passion for child-centric volunteer work, having contributed to causes including Blessings in a Backpack, the Think Before You Speak campaign and being a youth ambassador to the children of Bogota.
And, well, the soon-to-be 27-year-old — who's currently filming a new TV series and working on an album — hopes to lead by example in that respect, as well.
"[My mom] was always very philanthropic, always trying to do her part, and I think she really instilled that in my sister and I at a young age," Duff said.
"And, you know, for Luca to see me doing that... I think every mother out there raising a child wants them to grow up understanding what compassion is. We're all here, living together, and we have to lend each other a hand when we can and when the other needs it."
And you'll see personalized content just for you whenever you click the My Feed .
SheKnows is making some changes!