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    This Dentist And Mom Went Viral For Sharing Why She Doesn't Kiss Her Child On The Lips, And Spoiler Alert: It Has To Do With Cavities

    Beware the kiss.

    Dr. Joyce Kahng, DDS, is a 35-year-old cosmetic and restorative dentist from Costa Mesa, California who owns Orange and Magnolia Dental Studio. She's also a mom, and she recently went viral on TikTok for her series explaining why she doesn't — under any circumstances — kiss her child on the lips:

    @joycethedentist

    #greenscreen it was in that moment I realized bacteria is key. Oral hygiene can only make up for so much. #momtok #dentist #stemtok #momsoftiktok

    ♬ She Share Story (for Vlog) - 山口夕依

    In her most viral video — which currently has over 2.4 million views — Dr. Kahng explains that when she was in dental school, they did an experiment where they swabbed their mouths and grew their saliva in a petri dish. She found that she carried a larger amount of cavity-causing bacteria than her peers, which she could then pass on to her baby and also give him a lifetime of cavities. Hence, she made the decision that there would be no lip-kissing.

    Dr. Joyce's petri dish, full of bacteria, side-by-side with a peer's petri dish with barely any bacteria
    @joycethedentist

    BuzzFeed reached out to Dr. Kahng for more details, and she confirmed that kissing on the lips — as well as other things, like sharing utensils — can indeed transfer cavity-causing bacteria, especially in young children.

    "Bacteria can transfer through salivary exchange and this is more common for children, less common for adults," Dr. Kahng explained. "Children are not actually born with the bacteria that causes cavities. These bacteria are transferred to them at an early age, usually from their caregiver through activities like kissing and sharing utensils. After the age of 4 years old, a child’s oral microbiome has matured and is unique to them, making them more resistant during times of salivary exchange."

    A child at the dentist
    Peter Cade / Getty Images

    The bacteria in question is called streptococcus mutans, which Dr. Kahng describes as the "main major cariogenic pathogen." She said, "This bacteria feeds off of sugars in our diet and produces acid as a byproduct. Acid produced by this bacteria will dissolve the enamel layer and form a cavity...the more of this bacteria we have, the harder it will be to prevent decay."

    Dr. Kahng also confirmed that no matter how much we brush and floss, we still might end up with more cavities than the person next to us. "Some people are more predisposed to cavities than others regardless of their level of oral hygiene, and that's because we're not all the same! There are a number of factors besides oral hygiene that make people susceptible to this disease, such as bacteria and genetics."

    Dr. Squatch

    She continued, "This is not a disease of neglect, but rather susceptibility. If you're a patient who's susceptible, it only takes a low level of biofilm to express the disease. For a patient like this, preventing disease is an uphill battle."

    Dr. Kahng told BuzzFeed that she decided to create her series in order to share information and also to share her "mom struggles" when it came to keeping her baby's mouth cavity-free: "Despite my best intentions, I found it was much more difficult than anticipated to keep kisses from my little one, and also be mindful about pre-tasting his food and using his utensils. Sometimes it’s not easy to apply the understanding of science to real life (whether you're a doctor or not). I then realized a lot of people don’t know this science at all — I myself only learned it in dental school."

    "As a dentist, one of my goals is to educate others, and I don’t think this type of information should be a privilege. I also didn't want to shame anyone or make any moms feel bad if they'd already been sharing food, so I kept the videos less about what you 'should' do and more about what I have personally chosen to do given my caries rate."

    As for how to further prevent this kind of cavity susceptibility in children — and later on, adults — Dr. Kahng said, "It all starts with the oral health of the parents. I recommend my patients try to take care of their own active oral disease prior to pregnancy. This sets up good habits and an awareness to pass forward to their children. When I find out one of my patients is having a baby, I try to have a discussion with them about when they can start bringing their child to the dentist and start introducing brushing. Being on the front end of things is the goal — education is power!"

    And lastly, Dr. Kahng added, "Oral hygiene instruction should be personalized for the person, because people are susceptible to different things. To say it’s all about brushing and flossing is an oversimplification. Brushing and flossing is certainly important, but I think it’s imperative that we as healthcare professionals take the time to tailor recommendations and really help a patient understand their level of susceptibility. Only then can patients take true accountability of their oral health."

    As someone with about a million fillings in her mouth who's been shamed by countless dentists, words can't describe how RELIEVED I am by this information. You can follow Dr. Kahng on TikTok and Instagram to view her entire series and learn even more about oral health.