Gaps and Crowding in Baby Teeth: What's Normal?

"There are big gaps between his front teeth. Is that a problem?" It's one of the questions parents ask me most often, usually with a worried look. Here is the reassuring part: in baby teeth, gaps are usually a good sign. Let's look at what spacing and crowding can tell us, and what to expect as the adult teeth arrive.

Why gaps in baby teeth are good news

Adult teeth are noticeably bigger than the baby teeth they replace, especially the front teeth. Spaces between baby teeth mean there is room waiting for those larger teeth. Many children's gaps also widen a little between ages 4 and 6 as the jaws grow in preparation.

So if your toddler or preschooler has a "gappy" smile, that is usually exactly what we like to see.

What does crowding in baby teeth mean?

When baby teeth are touching tightly, or slightly overlapping, with no spaces at all, there is less spare room for the adult teeth. This does not guarantee a problem, because jaws keep growing, but it often means the adult teeth may be crowded too.

Tight contacts between baby teeth also matter for everyday care:

• Food and plaque collect where teeth touch, and cavities can start between teeth where a toothbrush cannot reach.
• Flossing becomes important once teeth touch. Floss picks or children's flossers can make this easier for parents.
• Your dentist may suggest X-rays at check-ups to look for decay between back teeth.

The "ugly duckling" stage

Between about ages 7 and 10, many parents get a surprise. The new adult front teeth may come in:

• With a gap between the two top front teeth.
• Angled outwards in a fan shape.
• Looking large for your child's face, and sometimes a little yellower than the baby teeth next to them.

This phase is so common that dentists nickname it the "ugly duckling" stage. In many children it improves on its own as the side teeth and the upper canines (eye teeth) come through, usually around ages 11 to 13, and push the front teeth closer together. So a gap at age 8 is often not a cause for alarm. Your dentist will keep an eye on it.

Losing baby teeth too early

Baby teeth act as natural place-holders. If a back baby tooth is lost early through decay or injury, the neighbouring teeth can drift into the empty space and leave less room for the adult tooth. This is one of the reasons we work hard to keep baby teeth healthy until their natural time. Sometimes a dentist recommends a space maintainer to hold the gap open.

Habits that can affect spacing

Long-term thumb, finger or dummy sucking, and in some cases mouth breathing, can affect how the teeth and jaws line up. Gently helping your child stop sucking habits, usually by around age 3 to 4, can help.

When to see the dentist or an orthodontist

Regular check-ups, usually every six months, let your dentist follow how the teeth and jaws are developing. Book an earlier visit, or ask about an orthodontic assessment, if you notice:

• Adult teeth coming in behind the baby teeth (a "double row"), and the baby teeth are not getting loose within a few weeks.
• A baby tooth lost early, especially a back tooth.
• Severe crowding, with teeth very twisted or overlapping.
• A crossbite (upper teeth biting inside the lower teeth), or the jaw shifting to one side when your child closes.
• Front teeth that stick out a lot, or don't meet at all.
• A gap that stays very wide after the canines have come through.

Many orthodontic groups suggest a first orthodontic check around age 7. Most children will not need treatment then, but some problems are easier to guide while the jaws are still growing.