Understanding Malocclusion: Causes, Effects, and Treatment

Occlusion refers to the relationships established when the upper and lower dental arches (maxillary and mandibular) come into contact. A normal occlusion would be the reference pattern or optimal situation in the occlusal relationship of both arches. Thus, we speak of normocclusion as the most balanced way of contacting or occluding the arches to fulfill the masticatory function and preserve the integrity of the dentition throughout life, in harmony with the bone structural set.

The differential diagnosis between occlusion and malocclusion is established by analyzing the contact relationships between both arches when the mandible is in forced positions. In this way, not only the relationship between arches is studied, but also the temporomandibular joint, which causes multiple pathologies in the mouth.

Any anatomical or functional alteration in the disposition of the teeth results in a pathological or abnormal occlusion or malocclusion.

Malocclusion can be caused by a bad position of the teeth within the arch or by a bad position of the arches with each other or by both overlapping reasons (mixed malocclusion).

When the cause is purely bone (due to an anomaly in the size or position of the maxillary bones) we will speak of bone malocclusion and it can lead to an affectation of any plane of space. We will talk about the different types of bone malocclusion according to the plane of the affected space:

• Transverse malocclusion: takes the width of the arches as a reference. Under normal conditions, the upper arch is larger than the lower one, so that, when the mouth is closed, the lower teeth are partially covered by the teeth of the upper arch. Any alteration in this physiological shape will lead to a transverse malocclusion.

Some examples of this group would be the cross bite and the scissor bite.

• Anteroposterior malocclusion: in the anteroposterior plane (from front to back) it also happens that the upper arch is larger than the lower one, so when occluding the upper incisor area protrudes from the lower one, forming what we call physiological incisor protrusion or mordex normalis.

Any alteration of this normality will lead to an anteroposterior malocclusion.

Some examples of this group would be the class II bite or augmented projection, the class III or anterior cross bite and the biprotusion.

• Vertical malocclusion: in normal conditions the upper teeth include the upper teeth when they occlude, giving rise to the so-called physiological overbite or horizontal crossing. Its normal value is between 2 and 5 millimeters. When this value is altered, a vertical malocclusion appears.

An example of this group would be the increased overbite and the open bite or mordex apertus.

It is also worth highlighting the malocclusion of dental origin whose main cause is the malposition of the teeth in the arch.

As mentioned above, mixed malocclusion is one that has a bone and dental component at the same time.