From four fillings in six years to none: how one question about when I ate changed what I thought I knew about my teeth

Nothing I tried was working

I am not a dental person. I am a forty-four-year-old man who assumed that if you brush twice a day and floss most nights, the subject is closed. For most of my thirties it seemed to be.

Then, over about six years, I had four fillings. Not one dramatic disaster — four small, boring repairs, spaced far enough apart that each one felt like bad luck rather than a pattern.

What I could not get past was the conversation that came with every one of them. I would ask what I was doing wrong. And I would get some version of: nothing, really. You brush well. Your gums are healthy. Some people are just more prone to it.

That answer is kind. It is also useless, and I now think it is not quite true.

What I tried, in order

Because of course I did not leave it alone. In roughly this sequence:

1. Brushing harder. Which achieved a receding gum on the upper left and a cold-sensitive tooth I still have. That one is permanent.
2. A better electric brush. Genuinely good. Made no difference to the count.
3. Flossing every night instead of most. Better gums. Same fillings.
4. Whitening toothpaste, then whitening strips. Teeth looked brighter for a while. Two weeks of sensitivity. Nothing else changed.
5. A stronger mouthwash. This is the one I want to come back to, because it turned out to be the most counterproductive thing on the list.

Five things, all of them sensible, all of them recommended to me by somebody. Not one of them touched what was actually going on.

Four appointments, four different explanations

What I did not notice at the time, because they were spread over six years and I only ever thought about one of them at once, is that I was given a different reason every single visit. I only saw the pattern when I wrote them down.

The first one, at thirty-eight. Upper right, small. I was told it was probably genetics, that some people simply have softer enamel, and that there was not a great deal to be done about that. I remember being almost relieved, because genetics is not a thing you can be blamed for.

The second, fourteen months later. Lower left this time. Now the explanation was technique. I was shown the correct angle to hold the brush at, and I went home and practised it in the mirror like a teenager. I got better at brushing. I did not get fewer fillings.

The third, at forty-one. This one was blamed on sugar, in general terms, along with a suggestion to cut down on sweet things. The awkward part is that I do not really eat sweet things. I do not take sugar in coffee, I do not eat dessert, and I had already stopped buying biscuits. Nobody asked what I actually drank, or when, and I did not think to volunteer it, because it never occurred to me that coffee was relevant.

The fourth, at forty-three. By then the explanation was more or less that this happens to some people, said kindly, in the tone you use when there is nothing else to say. That is the appointment that made me start looking things up on my own, which is a bad habit in most contexts and turned out to be the right instinct in this one.

None of those four answers was wrong, exactly. Genetics is real, technique matters, sugar matters. But every one of them was about what — what your enamel is like, what you do with a brush, what you eat. Not one of them was about when, and when turned out to be the whole thing.

The hidden cause most people are never told

The explanation eventually came from an implantologist — a dentist who does not repair teeth for a living but replaces them, which I suspect is why he thinks about the start of the process rather than the middle.

He asked me one question that nobody had asked before: not how I was brushing, but when I was eating.

Then he explained the thing that, once I had heard it, I could not believe had never been said to me in twenty years of appointments.

Brushing is mechanical. The damage is chemical.

Bristles scrape plaque off a surface. That works. But the process that ends in a filling is not scraping — it is dissolving. Enamel is a mineral, and minerals dissolve in acid.

There is even a number. Below a pH of about 5.5, enamel starts giving up mineral. Above that, mineral moves back in. It is a two-way exchange that runs every day of your life, and the only thing that has ever mattered is which direction runs more often.

Then he asked me to count my day

Coffee at seven. Breakfast at half seven. Second coffee at ten. Something at eleven because I had skipped lunch the day before. Lunch at one. An afternoon coffee. Dinner at eight.

Seven occasions. He explained that each one opens roughly a forty-minute cycle: five minutes for the pH to fall, fifteen or so underneath the line, twenty for saliva to bring it back up.

And it does not have to be sweet. The coffee counts. The sparkling water I drank all afternoon at my desk counts. The glass of wine counts.

Then he pointed out the thing that made me feel slightly stupid. I brushed at seven in the morning and eleven at night — the two moments of the entire day furthest away from every single one of those windows.

I was not doing it wrong. I was doing it at a time when nothing was happening.

And the mouthwash was making it worse

This is the part I am still slightly annoyed about.

I had been using a strong rinse specifically because I thought I needed more protection. He asked me to read the ingredients. It was built on alcohol.

Alcohol dries the mouth. Saliva is both the buffer that brings the pH back up and the fluid that carries mineral back into the surface. So the product I had bought for protection was reducing the one thing that was actually protecting me.

It also explained something I had never connected: why my breath was fine for an hour after using it and then, by mid-morning, was not.

How to restart the exchange in the other direction

Enamel is not made of “calcium” in a general sense. It is made overwhelmingly of one specific mineral: hydroxyapatite. When acid takes mineral out of the surface, that is exactly the mineral it takes.

So the idea is not complicated: if that is what is leaving, offer the tooth the same thing back. Not a substitute, not a coating. The same material, in a particle small enough to settle into the surface.

The other half is the bacteria producing the acid, and there the useful ingredient is xylitol. It resembles sugar closely enough that they take it up, and then cannot metabolise it. They fill up on something that gives them nothing.

The 1993 decision nobody mentions

This is the part I found most annoying once I knew it, because it is not new.

The work started at NASA. In weightlessness astronauts lose bone and tooth mineral, and the agency went looking for a way to give the body back its own hard-tissue material. A Japanese company came across that work while trading patents and took it in a dental direction. Their first toothpaste launched in Japan in 1980.

For years it was sold as a cosmetic, because approval to make a medical claim takes a long time. That approval came in 1993, when Japan’s Ministry of Health and Welfare recognised the material as an anti-caries agent and listed three effects: removal of dental plaque, filling of microscopic defects on the tooth surface, and remineralisation below the surface.

Thirty-three years ago. I had four fillings in that time and nobody ever said the word to me.

What I actually changed

Almost nothing, which is why I was sceptical.

1. I kept brushing twice a day. He was firm about this. Bristles remove plaque and nothing else does.
2. I stopped nursing drinks. If I want the sparkling water, I drink it. I do not sip it for an hour.
3. I stopped brushing straight after coffee. Enamel that has just been in acid is temporarily softened, and scrubbing it then removes more than it cleans.
4. I stopped the alcohol rinse.
5. I added three seconds after eating. Two or three sprays, at the teeth and the tongue, held for five seconds. No water, no sink, no spitting.

That last one is the only thing I added, and the only reason I could actually keep doing it is that it needs no bathroom. It is in a jacket pocket. I have used it in a car park, at a desk, and once, honestly, in a lift.

From “nothing works” to not thinking about it

The numbers, since I am not evidence

I am one person and one person is a story, not a study. So here are the figures the company records — the first measured in a laboratory, the other three from users over four weeks.

The whitening one is the one I would explain carefully, because it is not what people assume. Nothing is being bleached. A surface with fewer microscopic pits holds less pigment and reflects more light. That is why it comes with less staining rather than with the two weeks of sensitivity I got from the strips.

Less than the price of a coffee a week

On the three-bottle delivery it works out at €18.13 a bottle, and a bottle lasts about a month. I am on the delivery option for an unromantic reason: the entire idea depends on it being there after meals, and it is not there if the bottle ran out on Tuesday.

60-day guarantee

Every order carries a 60-day money-back guarantee, counted from the day it arrives. Keep the bottle — sealed, opened or empty, there is nothing to send back.

Questions I had