Common Orthodontic Problems
Class I occlusion is the ideal relationship with no crowding. What all orthodontists dream of (we just can't help it sometimes...)!
Meanwhile, a Class I Malocclusion occurs when the teeth relate well, but there is crowding and misalignment A malocclusion is when the relationship of your teeth when you bite together is off. This is usually assessed from a lateral or profile view.
Crowding is one of the most common orthodontic problems that we treat. Many speculate that it has evolved as a result of changes in diet. There simply is not enough space in each jaw to fit the number of teeth in the mouth. Crowding can lead to several issues besides general esthetic concerns. Dental crowding can cause dental impactions (i.e. adult teeth blocked out from erupting). Crowding is resolved by repositioning the teeth to have a broader archform or by extractions if severe.
Spacing is pretty self-explanatory, but can occur for several reasons. In these cases, the teeth may be too small relative to the jaws. Sometimes a muscle attachment (called a frenum) can be physically preventing the teeth to come together. Even thumb sucking and tongue habits can cause irregular spacing patterns.
A Class II Malocclusion occurs when the top teeth are forward relative to the lower teeth. These patients often exhibit a "Convex profile" or a small chin projection. Since the top teeth stick out, they are more at risk to trauma.
Less commonly we see a Class III Malocclusion. This is usually genetically driven, wherein the lower jaw (mandible) outgrows the upper jaw, which also tends to be undergrown. They exhibit a concave profile and very prominent chin. Sometimes a surgery is required to correct severe cases. In children, we see what we may call a Pseudo-Class III Malocclusion. This occurs when you habitually protrude the lower jaw forward often due to an interference that needs to be addressed.
A crossbite occurs when the upper teeth are narrower relative to the bottom teeth. In a Posterior Crossbite, since the lower jaw is wider, the top teeth sit on the inside and patients likely don't exhibit a broad smile. This is commonly the result of decreased upper jaw growth in terms of width in the transverse dimension. This relationship is often corrected orthopedically with a Rapid Palatal Expander.
An Anterior Crossbite occurs when the bottom teeth jut out forward relative to the top teeth. This commonly is associated with a Class III Malocclusion, since the lower jaw is overgrown. Here it is isolated to one tooth.
An Anterior Crossbite occurs when the bottom teeth jut out forward relative to the top teeth. This commonly is associated with a Class III Malocclusion, since the lower jaw is overgrown. Here it is present for all of the front teeth.
An open bite can occur with either the front or the back teeth. With an Anterior Open Bite, there is no overlap of the top teeth in the front of the mouth. This is often a result of habits such as thumb-sucking and/or a tongue thrust. Sometimes it is a result of genetics and excess growth in the vertical dimension. A Posterior Open Bite happens when teeth in the back don't meet, and can inhibit chewing or put stress on the front teeth. This is often genetic or due to a tongue habit.
As you may have guessed, this is pretty much the opposite of an open bite! A Deep Bite may accompany a Class II Malocclusion and is often the result of overeruption of the front teeth. This is treated by intruding the top front teeth, and sometimes the bottom front, as well.