Enamel Erosion and Acid Reflux: Why Teeth Wear Down Without a Single Cavity

Most tooth damage announces itself: a cavity aches, and a crack catches your tongue. Erosion does neither. It removes enamel evenly, a few micrometres at a time.

The first sign is usually not pain but a tooth that looks slightly shorter or slightly more yellow than it did a few years ago. By then a fair amount is already gone.

Erosion is a different problem from decay

A cavity is a hole made by bacteria. Bacteria in plaque feed on sugar, produce acid as waste, and that acid dissolves enamel in one concentrated spot. Fluoride helps, brushing helps, and a filling repairs the result.

Erosion has no bacteria in it. The acid arrives already made — from food, from drink, or from your own stomach — and it washes over whole surfaces rather than sitting in one place.

So it does not drill a hole. It thins everything it touches, uniformly, which is exactly why it goes unnoticed for years. There is nothing to catch a floss thread on, and nothing to see on an X-ray until the tooth has visibly changed shape.

The practical difference: a cavity is repaired. Erosion is stopped — and whatever enamel was lost before you stopped it does not grow back. Enamel has no living cells in it, so unlike bone or skin it cannot rebuild itself.

What the acid actually does

Enamel is mostly a mineral called hydroxyapatite, and it dissolves below a pH of about 5.5. Ordinary drinks sit well under that: most soft drinks are around pH 2.5, citrus juice around 3.5, wine around 3.4. Sparkling water is mildly acidic too, though nowhere near soda.

Saliva is the defence. It dilutes acid, washes it away, and carries the calcium and phosphate that let the enamel surface re-harden — a process called remineralisation. That takes time, which is where the real risk lies.

How often acid arrives matters more than how much. A glass of orange juice with breakfast is one acid event that saliva has all morning to recover from. The same glass sipped over two hours is a two-hour event with no recovery window in it.

This is why the habit that causes the most erosion is rarely the one people expect. It is not a treat. It is the water bottle with lemon in it kept on a desk, the sports drink taken slowly through a workout, the sparkling water sipped all afternoon.

The reflux version, and why it is worse

Stomach acid is about pH 1.5 to 2 — far stronger than anything you would drink. When it reaches the mouth, it erodes faster.

Two things make reflux the more damaging cause. First, it often happens at night, and salivary flow drops to almost nothing during sleep, so acid sits on the teeth for hours with no dilution.

Second, a large share of reflux is silent: no heartburn, no obvious symptom, sometimes nothing more than a sore throat or a hoarse voice in the morning. People with silent reflux have no reason to suspect their teeth are involved.

The wear pattern is a genuine diagnostic clue. Dietary acid tends to hit the outer surfaces of the front teeth, while reflux reaches the inner surfaces of the upper teeth and the biting surfaces of the back ones.

Those are places a toothbrush and a citrus habit do not reach the same way. When we see that pattern in someone with no dietary explanation, it is often the first time reflux has been raised with them at all.

Eating disorders involving vomiting produce the same inner-surface pattern, for the same reason. That conversation is handled privately and without judgement; the dental finding is simply a finding.

What it looks like before it looks like anything

Early erosion is subtle, and these are the things worth noticing:

• Yellower teeth that whitening does not change. Enamel is translucent; the dentine underneath is yellow. As enamel thins, more dentine shows through. The colour change is structural, so bleaching the enamel above it does very little.
• Edges that have gone see-through. Thinning enamel at the biting edge of the front teeth turns slightly transparent, often before any length is lost.
• Cupped dents in the back teeth. Small shallow craters on the chewing surfaces, sometimes with a rim of enamel standing proud around them.
• Sensitivity to cold that comes and goes, then stops coming and goes away — which usually means the tooth has laid down protective dentine, not that the problem resolved.
• Fillings that seem to stand slightly above the tooth. The filling has not risen. The enamel around it has worn down, and the restoration material has not.

What actually helps

Do not brush immediately after acid. Enamel is softened for a while afterwards, and brushing it in that state removes more than leaving it alone would. Rinse with water, or with water and a little baking soda, and wait about an hour.

Change the pattern rather than the item. Drinking something acidic with a meal and finishing it in a normal span does far less damage than sipping the same thing over an afternoon. Nobody needs to give up citrus.

Get reflux treated as reflux. If the wear pattern points at it, the dental side is downstream of the real problem. That is a conversation with a physician or a gastroenterologist, and it matters more than anything done to the teeth.

Fluoride, at higher strength than a supermarket tube. A prescription-strength fluoride toothpaste hardens the enamel surface and reduces sensitivity. It slows erosion; it does not reverse it.

A night guard when grinding is also in play. Worn enamel and night-time clenching frequently arrive together, and once enamel is soft from acid, grinding removes it much faster. Treating one and not the other leaves half the cause running.

When teeth have already got shorter

Enamel does not regenerate, so meaningful loss is rebuilt rather than repaired. What that takes depends on how much is gone — bonding to restore edges in mild cases, and crowns or veneers where the shape and height of the tooth need rebuilding.

There is a reason this is planned digitally rather than tooth by tooth. Widespread erosion changes how the teeth meet, so rebuilding a few in isolation puts the load somewhere new and often breaks something else.

Scans and photographs let the whole bite be worked out on screen first. A Smile Reveal visit is where that plan is put in front of you, including how much of the wear is worth restoring now and how much is better monitored.

The measurement is the useful part. Erosion is slow, and a single appointment cannot tell you whether it is still active. Scans taken a year apart can, because the same tooth can be compared to itself. If the wear has stopped, nothing needs doing. That is worth knowing before anyone picks up a drill.