What Is a Class III Malocclusion?

Misalignment refers to the deviation of the normal contact relationship between the upper and lower teeth.

Wrong teeth

Right!

Misalignment refers to the deviation of the normal contact relationship between the upper and lower teeth.

When the patient bites, use the tongue depressor to open each side of the cheek. Check the relationship between the two sides of the mouth. Normally, the teeth in the dental arch on each side are arranged side by side to form a smooth curve, and the upper jaw The anterior teeth cover the upper 1/3 of the mandibular anterior teeth. The buccal tips (lateral) of the maxillary posterior teeth are outside the corresponding buccal tips of the mandibular posterior teeth. On each side of the oral cavity, the mesial cheeks of the first permanent molar of the maxilla The tip of the tooth bites in the buccal groove of the first permanent molar of the lower jaw. Since the outer part of all the upper teeth is normally outside the lower jaw, the lips and cheeks will not be between the upper and lower teeth, so they will not be bitten. The arc formed by the tongue surface (inner surface) is smaller than that formed by the maxillary teeth, so the tongue is confined within it, reducing the possibility of biting the tongue when the upper and lower teeth bite. All teeth are in contact with their corresponding teeth, so it is strong. The chewing force (which may be greater than 45 kg in the molar area) is widely distributed. If this force is only applied to a few teeth, it will cause loosening.

Mistakes are often divided into three main forms (Angle classification): Class I, the maxillary molars are normal, but the anterior teeth are crowded or misaligned. Class II: Mandibular and mandibular molars are moved backward, and the lateral view of the face is convex. Type III: The relationship between mandibular and mandibular molars and maxillary molars is anterior process. At the same time, the buccal tip of one or more mandibular teeth is located outside the corresponding maxillary tooth tip.

Mistakes often result from the disproportion of the size of the jaws to the size of the teeth-that is, the small jaws have large teeth, and the jaws cannot provide a suitable position for the arrangement of the teeth. There are many other reasons for mistakes (Table 106-1), such as missing Teeth. When permanent teeth are missing, the adjacent tooth is displaced and the corresponding tooth is extended, which leads to error. If you do not wear a fixed bridge or partial denture, you cannot prevent this movement. When the deciduous teeth at the end of the dental arch are prematurely detached The first permanent molar often moves forward without leaving enough space for the eruption of other permanent teeth. The interdental retainer can prevent this movement. The deciduous teeth of patients with clavicle and skull dysplasia can stay for a long period of time, resulting in many permanent teeth. No eruption. Mistakes after facial trauma? May indicate tooth displacement or jaw fracture.

Diagnosis and treatment

Children should have their first routine oral examination at the age of 2 years. If there is any doubt, they should consult a dentist as soon as possible because early orthodontic treatment can reduce expensive and difficult techniques in the later stages.

Miscorrection is mainly for aesthetic and psychological reasons. Mistreatment can enhance caries to special teeth, broken anterior incisors and resistance to periodontal disease, and can improve language, chewing and appearance. Teeth, selective tooth conditioning and restorations alleviate early contact, use artificial crowns or inlays to get bite contact with sub-flat teeth, and other methods to improve the relationship. With the help of orthotics, the teeth are gentle and continuous. Strength, gradually moving the teeth and reconstructing the alveolar bone. Some patients need to extract one or more permanent teeth to provide sufficient clearance for other teeth to get eruption and a stable arrangement. The patient wears plastic and archwire retainers at night. 2 to 3 years until the teeth are stable in the new position. When the orthodontic treatment alone cannot meet the requirements, surgical (orthognathic surgery) correction of errors caused by abnormalities of the jaw is suitable. When wearing full dentures If you are wrong, you should consider making a new pair of dentures.