Dental malocclusion

Definition

We talk about dental malocclusion when the teeth of the upper arch are not perfectly aligned with those of the lower arch. In other words, dental malocclusion is an abnormal relationship between the teeth of the jaw and those of the jaw.

In physiological conditions, the dental arches relate through harmonic and balanced relationships in order to adequately perform the masticatory and phonetic functions. Dental malocclusion occurs precisely when this balance is denied. In such circumstances, the imperfect occlusion of the dental arches can cause functional or morphological (structural) disharmony, such as to have negative repercussions also on other anatomical sites. Just think, for example, that a dental malocclusion - in addition to chewing disorders - can also cause neck pain (cervical pain), back pain, headache and tinnitus (ringing in the ears). Clearly, the symptoms depend on the severity of the disease: while dental malocclusions dependent on inadequate behavioral habits can be treated with mobile or fixed orthodontic appliances, the most severe forms (subject to genetic abnormalities) require corrective orthodontics.

Causes

The cause of dental malocclusion is often hereditary, which means that the structural anomaly is passed down genetically.

However, in some patients, dental malocclusion does not depend on genetic malformations, but rather on incorrect behavioral attitudes or other diseases, such as:

• Infantile habit to suck the thumb, push the tongue against the teeth, use the pacifier after the third year of life, prolonged use of the bottle
• Bruxism (tendency to clench teeth, also and especially during the night)
• Malformed or not perfectly successful dental operations, such as dental fillings, tooth encapsulation and dental implant
• Loss of one or more permanent teeth
• Teeth severely chipped and not rebuilt
• Tumors of the mouth and jaw
• Mandibular fracture in childhood
• Rheumatoid arthritis (rare)

Classification

Classification of dental malocclusions (outline)
1st grade dental malocclusion	The bite is normal, but the teeth of the upper arch slightly dominate those of the jaw
2nd degree dental malocclusion (retrognathism and dental crowding)	The upper arch overhangs the teeth of the lower arch considerably and clearly. The chin is elusive and, generally, the interdental space of the upper incisor teeth, as well as that of the lower incisors, is very pronounced
3rd degree dental malocclusion (progeny or reverse bite)	The teeth of the jaw are evidently more advanced than those of the jaw

Signs and symptoms

Please note

Remember that only a very small percentage of people have perfect dental alignment. However, it often happens that dental malocclusion is so minimal that it goes completely unnoticed. In such circumstances, the patient does not accuse any appreciable symptoms.

COMMON SIGNS

Dental malocclusion does not always manifest with the same signs. The most common types of dental occlusion are listed below:

• dimensional difference between upper and lower arch
• jaw size too high or too narrow for the shape of the teeth
• overcrowding of the teeth
• inverse bite (the lower arch goes further forward than the upper arch)

SYMPTOMS

Dental malocclusion can cause mandibular and extra-mandibular symptoms, even involving the spine.

The diversity of symptoms (as well as their severity) depends on the extent of dental malocclusion:

• Masticatory difficulties
• Poor face alignment
• Increased risk of caries, periodontopathies (eg gingivitis, pyorrhea, gingival bleeding) and temporomandibular changes
• Tendency to breathing with an open mouth
• Tinnitus or ringing in the ears, dizziness and otalgia (symptoms often associated with cranio-mandibular disorders)
• Breathing difficulties: chronic cough, rhinosinusitis, asthma and chronic bronchitis
• Repercussions on the vertebral column: back pain
• Gastro-esophageal reflux disease (less frequent)
• Language difficulties (rare)

Diagnosis

We have seen that there are different types of dental malocclusion: while some forms are particularly evident, others can be discovered by chance during a normal routine dental examination.

The doctor proceeds with a mandibular check: slightly pulls the jaw outward, asks the patient to bite and tighten his teeth to check bite and dental occlusion mode. The specialist will also investigate and analyze any symptoms accused by the patient.

Among the diagnostic tests, radiographs of the dental arch, head / skull, and face are often required to verify the severity of a dental malocclusion. In most cases, it is necessary to cast the patient's teeth to reproduce a plaster model of the dental arches.

The dentist may possibly rely on another health figure specialized in kinesiology or orthodontics.

Care

As mentioned, dental malocclusions do not always require intervention, since some variants do not give any symptoms worthy of pathological significance.

A moderate or severe malocclusion requires a specific intervention instead:

1. Moderate or medium-sized dental malocclusions can be corrected according to several approaches:
   • Orthodontic interventions: application of fixed or mobile orthodontic appliances to remedy crowding of the teeth
   • Extraction of teeth: when the crowding of the teeth is due to the presence of one or more molars or wisdom teeth that push the others, it is necessary to proceed with the extraction
   • Correction of incongruous behavioral habits:
     • application of bite to correct bruxism (possible cause of dental malocclusion)
     • use of special passive devices able to guide and facilitate masticatory forces
     • avoid sucking the thumb and drinking from the bottle (for small children affected or predisposed to dental malocclusions)
2. Congenital dental malocclusions often require invasive surgical treatments, since the altered bite is particularly obvious and unaesthetic, and causes serious health problems for the subject. Mandibular lengthening / shortening surgical remodeling must be considered to correct a severe dental malocclusion.