Is Midline Misalignment a Problem?


The human body is miraculously symmetric. While most patients have good symmetry, no one is actually perfect. Perhaps there is one ear which is slightly higher than the other or one foot is a half-size larger than the other. It is relatively common to have features which are not perfectly symmetrical.


In some cases, patients may have a smile which appears to be slightly off-center. This may be caused by a condition called midline misalignment. Fortunately, there are treatment options to resolve this.


There is a dividing line located between the top and bottom teeth. This is called the midline. If imagining a line down the center of the face from forehead to chin, the line should pass the nose and go between the front teeth. When this does not occur, it means the teeth have shifted beyond the midpoint with a condition called midline misalignment.


Below are common causes for midline misalignment.


Early Loss of Baby Teeth

The baby teeth are critical in promoting healthy speech and eating habits, but have other important roles too. These teeth make space for the permanent teeth later in life. Primary teeth which fall out too early can allow for drifting of the permanent teeth into the empty space. This can result in the movement of the midline.



Many young children suck their thumb or a pacifier as a calming technique. As they age, their permanent teeth begin to erupt. When the child continues to suck their thumb or a pacifier, it can result in orthodontic issues such as a deviated midline. The teeth can slowly shift because of the constant sucking pressure.


Adult Teeth

Patients may lose a tooth due to trauma or decay. In other cases, the adult tooth may fail to develop or erupt. This can allow for the remaining teeth to shift into the open spot.


Spacing Problems

When the teeth are crowded, have significant gaps, are oversized, abnormally small or have any other type of issues, it can negatively impact the spacing and midline alignment.



A crossbite is a form of malocclusion or bite issue. Patients with a crossbite have teeth which do not properly fit together. This means the upper teeth fit inside lower teeth, instead of correctly aligning on the outside. When there is a deviated midline, it can suggest the presence of a posterior crossbite. This means the top back teeth slant inwards or fit inside the bottom teeth in the back of the mouth.


A minor midline shift may not be overly concerning or problematic, however, if the teeth are noticeably out of alignment, patients should follow up with their dentist to discuss treatment options. There are several things which can cause midline misalignment so the dentist will need to complete a thorough examination.


In cases of a minor shift, it can often be treated with traditional braces or invisalign. Crossbites may require braces or aligners combined with rubber bands in order to achieve proper alignment. Palatal expanders can aid in correcting a severe crossbite.


A deviated midline may simply seem like a cosmetic issue, however it can lead to big problems such as bad chewing habits, jaw pain, damaged teeth, headaches, and other challenges associated with a malocclusion.

It is not realistic for most patients to achieve absolutely perfect symmetry. Patients who desire a healthy and balanced smile should follow up with their dentist to discuss possible treatment options.

Is Misaligned Midline Normal