Intrusion is a type of orthodontic movement in which a tooth is moved in a superior direction in order to reduce its vertical dimension. It is commonly used to correct a deep bite or a protruding incisor. Intrusion is achieved by using an archwire to apply force directly to the tooth or by using a power arm or a band with a wire to transfer force from the archwire to the tooth. The force is usually applied on the labial or buccal side of the tooth.
Types of Intrusion
There are two main types of intrusion: direct and indirect.
Direct intrusion is done by placing the archwire directly on the tooth and applying a force to the tooth. This is the most commonly used method of intrusion.
Indirect intrusion is done by attaching a power arm, band, or wire to the archwire and then applying force to the tooth. This method is less commonly used because it often requires more time and effort to achieve the desired effect.
Benefits of Intrusion
Intrusion can be used to correct a deep bite or a protruding incisor. It can also be used to reduce the vertical dimension of the teeth, which can improve the aesthetic appearance of the smile. Intrusion can also help reduce the risk of periodontal disease, since it creates a more even bite.
Risks of Intrusion
The main risk associated with intrusion is that it can cause damage to the teeth and the surrounding gums. It can also cause the teeth to become more sensitive and can lead to root resorption. Additionally, it can cause the teeth to shift out of alignment and can interfere with the natural eruption of the teeth.