Why do I have a gap between my back teeth that wasn't there before?

Back teeth don't usually move on their own

Front teeth get blamed for shifting because you can see them in the mirror every day. Back teeth shift too, you just notice it later, usually when food starts packing into the space or your tongue finds the gap while you're thinking about something else.

The most common reason is that a tooth nearby was removed at some point, maybe years ago, and nothing replaced it. Teeth lean into empty space slowly. A molar can tilt or drift a millimetre or two a year without you feeling anything until the gap next to it is obvious. If you've had an extraction on that side and never got an implant or bridge, this is the likely explanation.

The second common cause is decay on the side of a tooth, between the contact points. This kind of cavity doesn't always hurt and doesn't show up when you look in the mirror, because it's hidden between the teeth. As it grows, it can actually widen the space you see, or change the shape of the tooth enough that food starts catching there. A bite-wing X-ray picks this up easily, which is why routine checkups matter even when nothing seems wrong.

Gum and bone changes are the quieter cause

If you've noticed your gums receding, bleeding when you brush, or a bit of looseness in that area, the gap might be coming from bone loss around the roots rather than tooth decay or drift from a missing neighbour. Gum disease reduces the bone that holds teeth firmly upright and together. As support drops, teeth can fan out slightly, and back teeth often move sideways rather than forward, which opens a gap you didn't have before.

Grinding at night is worth mentioning too. Heavy, repetitive force on back teeth over years can wear down the contact points between them or gradually shift a tooth's position, especially if you already have some bone loss working against you. People with a grinding habit often don't know they have it until a dentist points out the wear patterns.

What to do about it now

None of these causes fix themselves, and none of them are urgent emergencies, but all of them tend to get more expensive to treat the longer they sit. A gap that's from drift after a missing tooth usually needs that missing tooth replaced, often with an implant, to stop the neighbours from continuing to move. A gap from decay needs the cavity treated, sometimes with a filling, sometimes a crown if enough tooth structure is compromised. A gap from bone loss needs a periodontal assessment and a cleaning plan, because closing the space cosmetically without treating the gum disease underneath it won't hold.

At The Dentist in Al Qusais, new patients get a free first checkup, which includes the X-rays needed to actually see what's happening below the gumline and between the teeth rather than guessing from the outside. Dr. Faris Alkhanafseh and Dr. Mohammad Nour will tell you plainly which of these three things is going on and what it takes to stop it moving further. If you've spotted a new gap, book a visit through WhatsApp or thedentist.ae/book before it turns into a food-trap you're dealing with at every meal.