Malocclusion of teeth is a misalignment of the biting surfaces of the upper and lower teeth. It’s a deviation from the normal occlusion of teeth where all the upper teeth fit over the lower teeth. People with normal occlusion have a perfect bite and the points of the molars of each set of teeth fit the grooves of the molars of the other set. Thus, the maxillary and mandibular teeth have contact, and this helps in the proper mastication of food. However, most people suffer from malocclusion of teeth that can vary from slight to severe.
Causes of Malocclusion
The reasons why malocclusion occurs may be attributed to a difference in the sizes of the upper and lower jaws or a difference in the size of the jaw and the teeth. These can cause crowding of the teeth and imperfect bites such as overbites, underbites or crossbites. Childhood defects, such as a cleft palate and lip, can also cause malocclusion of teeth as can the prolonged use of bottles in childhood or the sucking of a thumb or a pacifier. Some people have impacted teeth, others have more teeth or fewer teeth, and yet others have teeth that are not regular in shape. All these factors can cause malocclusion of teeth.
Classification of Malocclusion
Edward Angle first classified malocclusion on the relative position of the upper first molar. For a perfect occlusion, the cusp of the upper first molar should rest in the groove of the lower first molar. All the other teeth should also fall in the line of occlusion. Any variation was deemed by Angle as a malocclusion and he classified malocclusion into three classes.
Class 1 Malocclusion (Neutrocclusion)
This is the most common type of malocclusion in which the upper teeth overlap the lower teeth. The bite, however, is normal. The cusp of the upper first molar rests in the groove of the lower first molar. However, there might be spacing, overcrowding, under eruption or over eruption with respect to the other teeth.
Class 2 Malocclusion (Distocclusion)
This type of malocclusion is also known as retrognathism or overbite. The upper teeth and jaw overlap the lower jaw and teeth severely, and the upper molars are very much anterior to the lower molars. In this class of malocclusion, either the front teeth are protruded or the back teeth overlap the central teeth.
Class 3 Malocclusion (Mesiocclusion)
Also known as prognathism, this class of malocclusion occurs when the lower front teeth are more prominent than the upper front teeth and the patient has a large lower jaw or a short upper one. This causes the teeth to be misaligned and the lower incisors can touch the gingival tissue of the upper arch of the jaw.
Other Types of Malocclusions
Although the three classes mentioned above are the main types of malocclusion, there are other kinds of malocclusion that people suffer from. People with long faces or those with a tendency of thumb sucking or tongue thrusting tend to have an open bite, whereas people with short faces or those whose molars are underdeveloped tend to have a deep bite.
Orthodontic treatment can help rectify malocclusions and if you feel that your bite isn’t perfect and your teeth are crowded or protruding, advice and treatment from an orthodontist can improve the condition of your teeth.