First Molars & Preventing Cavities in Children

Hi Dr. Ellie,
My 7 year old son does not have any molars yet. He sees his dentist every 6 months and has never had a cavity. He doesn’t need the ACT rinse yet, does he? From what I gather from your blog he won’t need the ACT until his molars come in? On the other hand his sister, who’s 8, had a cavity to my surprise this past year. I wish I had known that it was possible to heal a small cavity, but we had it filled because that was what the doctor suggested. This daughter sleeps with her mouth open and has bad breath. I’ve started her using the Listerine in conjuntion with the ACT and all children will be on xyltol when it arrives. Even though she’s 8 I thought with her history that the Listerine would help…is that correct?Thanks,


Hi S,

Thanks for your message. You are correct that the priority for a 7 year old without permanent molars yet is xylitol in adequate amounts. In Scandinavia they start xylitol in Preschool – ensuring the kids’ mouths are ready for the eruption of new molars. 7 is quite late for these molars that often erupt during Kindergarten ages.

The first bacteria to get into the biting surface grooves of molars – become the dominant bacteria of the mouth. Ensuring that the mouth bacteria are healthy BEFORE the eruption of molars is the best way to achieve this ( and it usually takes 6 months of 5-10 grams per day to make the oral bacteria truly healthy).

Fluoride comes into play when we need to stimulate the formation of the Pellicle layer over new molar teeth. It usually takes about a year for Pellicle to form, but in conjunction with ACT dilute fluoride, xylitol and good diet – you can often get this protective layer to form in less than half that time.

Remember that cheeses and organic dairy are perfect endings to meals and make great snacks for teeth.
Limit juices and anything acidic to during a meal – and end the meal with a tooth-protective food or xylitol.

When anyone mentions bad breath – I suggest looking for some kind of bacterial transfer – xylitol will be very helpful. Check toothbrushes are clean every day – that they dry completely between uses, and are stored at least 10 feet from any toilet area.

Hope this helps,


More information can be found on this topic and more at:

Categories: Children's Teeth, Q&A with Dr. Ellie


  • Lorena says:

    Hi Dr Ellie
    My 7 years old permanent lower front teeth are misaligned, for this reason food always get trapped between this two teeth, I always make sure she brushes her teeth twice a day sometimes even 3 times a day but despite this I noticed that between her teeth specially around the gum line they started to become yellow and looks a bit rough.
    Worrying that is the beginning of a cavity I started to use dental floss to see if this can help but is difficult to remove some bits at the bottom of the teeth around the gum line, it seems like she has tartar there. Also I started to use xilitol (Total sweet which is the only one I could find, I live in London) I take one teaspoon and dissolve in a bit of water and I make her use as a mouth wash after every main meal and I am also using the original crest tooth paste that you recomend, I am not using the Act because because I am not sure she is good at splitting well.
    I took her to the pediatric dentist 3 weeks ago and she said everything was fine no cavities.
    Please help me what else should I do to help her. do you think the way I am using xilitol is ok, will it help to get rid of the tartar will it have the same effect as when drinking it, should I use the ACT? can she get dental fluorosis if exposed to too much fluoride at her age? Should I continue with the dental floss sometimes I am worry I could hurt her gums . I will really appreciate any advice you could give me thanks in advance.

  • Loree says:

    Hi Dr. Ellie,

    I am a practicing dental hygienist and also practice as a orofacial myofunctional therapist (OMT). I recently had a client come in for OMT and the child had crowns on all her primary molars. The mother then explained she felt her daughter had more treatment provided then expected when they sedated her. She had become very alternative and wanted to heal her daughters teeth naturally.

    She then asked if I could provide her with any improvement to her oral hygiene. I did a quick assessment of her teeth and found a hole through the occlusal of her lower right first molar that went 3 mm beneath the enamel layer into the dentin. Note as a dental hygienist I cannot diagnose a cavity. The mother feels with all the information out there about healing teeth that she can reverse the tooth in this current state.

    No one gets into these details and many are not dentists who are claiming to reverse cavities. I would hate to see this 7 year old girl loose her tooth and would like to have someone with an alternative perspective provide a solid recommendation who comes more from your perspective that I can provide her.

    I have not read anywhere to confirm reversing a cavity that has gone through the enamel and progressed well into the dentin can be reversed. I would really appreciate your perspective on this so I can provide a dentist’s opinion who believes in cavity reversal is possible. The question is if a cavity has gone to deeply can it truly be reversed?

    Thank you in advance.

    • I agree this is a serious problem – and the whole family must understand cavities are a disease of bacteria compounded by fungal issues. Cleaning toothbrushes and using xylitol need to be uppermost in their minds! In addition, of course,

      1. Diet, nutrition, frequency of snacking must all be addressed.
      2. The entire family must be on a xylitol program – daily use, after every meal ( at least for the next 6 months).
      3. A seven-year old can use my system of care and I believe Closys is an important part of the routine for hidden or non-accessible cariogenic pathogens.
      4. The child will need supervision to ensure she gets this complete three-rinse system correct. This is serious work for a few months, but it need not be quite so serious once the cavity has remineralized.
      5. If there is any way for you to access the Canary System dental equipment – this would be an excellent tool for you to measure improvements. Let me know if you want to talk more about this case – we could discuss on the phone – leave me a message at our contact page. Here is a link to the Canary System – originally designed to measure remineralization – but when no one was interested, they now sell “to increase production by locating early cavities” LINK

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