Crossbite

What this means for your treatment decision

Many dental crossbites respond well to aligners, sometimes with added expansion; skeletal crossbites may need more than tooth movement.

Anterior versus posterior crossbite

A crossbite is described by where it occurs. An anterior crossbite involves one or more upper front teeth sitting behind the lower front teeth, which can resemble an underbite in a single tooth or a small group. A posterior crossbite involves the back teeth, where the upper arch is narrower than the lower arch at the sides, causing some upper back teeth to sit inside their lower counterparts. The two patterns are evaluated and treated somewhat differently, and a patient can have both at once.

Dental versus skeletal crossbite

A dental crossbite is caused by individual teeth being tipped or positioned incorrectly, while the jaw bones themselves are reasonably matched in width. This type generally responds to careful tooth movement and sometimes a degree of dental arch expansion. A skeletal crossbite reflects an actual narrowing or asymmetry of the jaw bones — most often the upper jaw — and tooth movement alone has limited ability to correct the underlying bone width, particularly once growth has finished.

Signs worth paying attention to

• The jaw visibly shifts to one side as the teeth come together
• Wear facets or flattened edges concentrated on specific teeth
• Gum recession isolated to a single tooth, often on the lower arch
• A noticeably asymmetric smile or facial appearance
• Clicking or discomfort in the jaw joint on one side

Why a crossbite needs a hands-on exam

A scan shows tooth position, but confirming whether a crossbite is dental or skeletal, whether the jaw shifts on closing, and whether the asymmetry involves bone or just teeth requires a clinical bite exam, often supplemented with photographs taken from the front and side. Age matters here too — younger patients with a narrow upper jaw have access to growth-friendly expansion approaches that aren't available the same way once the jaw has finished developing.

How aligners or braces correct a dental crossbite

• Tipping or torquing individual teeth back into normal alignment relative to their opposing tooth
• Using attachments to give aligners better control over the specific tooth movements involved
• Coordinating upper and lower arch movement together so the correction holds
• In some cases, limited aligner-based expansion of the dental arch to create room

When expansion or other appliances are needed

If a crossbite is skeletal rather than purely dental — typically a narrow upper jaw — aligners and braces have a limited ability to correct it on their own. In growing patients, this is often when a palatal expander or similar growth-guided appliance is discussed. In adults, options may be more limited since the growth plates involved have fused, and a more significant procedure may be the only way to achieve true skeletal correction if the narrowing is substantial — something discussed honestly rather than minimized.

What correcting a crossbite feels like

Expect noticeable bite changes during this type of correction, since the goal is literally changing how upper and lower teeth meet, not just straightening their appearance. Some patients feel pressure concentrated in the back teeth during posterior crossbite correction, or a temporary sense that their bite feels different or unfamiliar as teeth move into a new relationship. This settles as the correction completes and stabilizes.

Retention is especially important for crossbites

Crossbite corrections, especially posterior ones involving expansion, have a meaningful tendency to relapse if retention is inconsistent, because the surrounding muscles and tissues were working against the old, narrower relationship for years. A dedicated retention plan, sometimes including a specific retainer design for the correction you had, is part of making a crossbite fix durable rather than temporary.

Questions patients ask