"It's just a baby tooth, it's going to fall out anyway" — that's usually the first thought a parent has when they notice a cavity in their child's tooth. It sounds reasonable: if it's not a permanent tooth, how much could the cavity really matter?
But that reasoning doesn't match what the research on this actually shows. In this article, I explain what untreated baby tooth decay can really lead to, based on the findings of a systematic review published in 2023.
Key Takeaways
- A 2023 systematic review published in Medicina found that untreated early childhood caries can lead to pain, multiple inflammations, and early loss of the baby tooth.
- The same review notes that this decay can damage the developing permanent tooth germ underneath, which can affect eruption timing and jaw development.
- Nutritional behavior, speech development, and chewing-swallowing function are also areas that can be affected by untreated decay.
- The "it'll fall out anyway" reasoning ignores both the current and future effects of the decay — a baby tooth cavity isn't an unimportant finding on its own.
- If you notice a cavity in a baby tooth, it's recommended to have it seen by a dentist even if the tooth isn't hurting yet.
The Myth: Where Does "It'll Fall Out Anyway" Come From?
This reasoning has a certain logic to it: baby teeth really do fall out at a certain age and get replaced by permanent teeth. The mistaken conclusion that follows is: "since it's going to fall out anyway, the cavity doesn't matter." This is one of the most common reasons parents delay or skip treatment for a baby tooth cavity altogether.
But as I explained in "When Should Your Child First Visit the Dentist?", baby teeth have active functions — supporting nutrition, speech, and guiding permanent teeth into place — so being "temporary" doesn't mean being "unimportant."
The Evidence: What Untreated Baby Tooth Decay Actually Leads To
A systematic review published in Medicina in 2023 examined treatment decisions for early childhood caries (the clinical term for baby tooth decay) and what happens when it goes untreated. According to the review, untreated decay can lead to pain, multiple inflammations, and early loss of the baby tooth — both an aesthetic and a functional problem (Wolf TG, Campus G. "Cost-Effectiveness of Treatment Decisions for Early Childhood Caries in Infants and Toddlers: A Systematic Review." Medicina (Kaunas), 2023;59(10):1865, retrieved 2026-08-31).
This is exactly what the "it'll fall out anyway" logic misses: in the time between now and when the tooth would naturally fall out, the decay can already be causing pain and infection. That's a real consequence the child experiences now — one that delaying treatment doesn't undo.
How Does It Affect Permanent Teeth?
The second key finding from the same review is that this decay can damage the permanent tooth germ developing underneath the baby tooth. That damage can disrupt the permanent tooth's eruption timing and affect jaw development (Wolf & Campus, ibid.).
This connects directly to the point I made in "When Should Your Child First Visit the Dentist?" about baby teeth guiding permanent teeth into position: if a baby tooth is lost early, or the germ beneath it is damaged by decay, that guiding function can be disrupted too.
Effects on Nutrition, Speech, and Overall Development
The review also shows that the impact of untreated decay isn't confined to the mouth: speech development disruptions, inadequate nutritional behavior, and chewing-swallowing dysfunction are among the other consequences linked to this decay (Wolf & Campus, ibid.).
The reasoning is straightforward: chewing becomes harder with a painful or damaged tooth, which can affect a child's eating habits; discomfort and structural changes in the mouth can also make it harder to form certain speech sounds correctly.
When Should You Take It Seriously?
The practical takeaway here is clear: if you notice decay, a brown spot, or chipping on a baby tooth, the tooth not hurting yet isn't a reason to wait. As I explained in "When Should Your Child First Visit the Dentist?", early childhood caries ("baby bottle tooth decay") can progress quickly — decay caught early is usually manageable with a simpler intervention.
That doesn't mean every cavity is an emergency — what intervention is needed, and when, becomes clear after an exam. But "let's wait, it'll fall out anyway" doesn't have scientific backing as an approach.
Bottom Line: Is It Really Unimportant?
No. Regardless of the tooth being temporary, baby tooth decay is a real clinical finding with the potential for pain, infection, damage to the developing permanent tooth germ, and effects on nutrition and speech development. "It's going to fall out anyway" doesn't erase any of these consequences. If you notice decay in your child's tooth, the safest step is to have it seen by a dentist.
Frequently Asked Questions
Is it worth filling a baby tooth that's going to fall out anyway?
Yes — a filling reduces the risk of pain and infection for however long the tooth remains, and it also helps protect the permanent tooth germ developing underneath it.
Can an infection in a baby tooth spread to the permanent tooth?
Untreated decay or infection can damage the permanent tooth germ developing underneath it, which can affect its eruption timing and structure.
I noticed a cavity but the tooth doesn't hurt — should I still go?
Yes — the absence of pain doesn't mean the decay isn't progressing; decay caught early is usually manageable with a simpler intervention.
How can I prevent baby tooth decay?
Regular cleaning starting from the first tooth, avoiding prolonged bottle contact with sugary liquids (especially overnight), and regular dental check-ups form the basis of prevention.