Traumatic Injuries

Concussion
An injury to the tooth-supporting structures without increased mobility or displacement of the tooth, but with pain to percussion.

Subluxation
An injury to the tooth supporting structures resulting in increased mobility, but without displacement of the tooth. Bleeding from the gingival sulcus confirms the diagnosis.

Extrusion
Partial displacement of the tooth out of its socket.
An injury to the tooth characterized by partial or total separation of the periodontal ligament resulting in loosening and displacement of the tooth. The alveolar socket bone is intact in an extrusion injury as opposed to a lateral luxation injury. In addition to axial displacement, the tooth will usually have an element of protrusion or retrusion. In severe extrusion injuries the retrusion/protrusion element can be very pronounced. In some cases it can be more pronounced than the extrusive element.

Lateral luxation
Displacement of the tooth other than axially. Displacement is accompanied by comminution or fracture of either the labial or the palatal/lingual alveolar bone.
Lateral luxation injuries, similar to extrusion injuries, are characterized by partial or total separation of the periodontal ligament. However, lateral luxations are complicated by fracture of either the labial or the palatal/lingual alveolar bone and a compression zone in the cervical and sometimes the apical area. If both sides of the alveolar socket have been fractured, the injury should be classified as an alveolar fracture (alveolar fractures rarely affect only a single tooth). In most cases of lateral luxation the apex of the tooth has been forced into the bone by the displacement, and the tooth is frequently non-mobile.

Intrusion - Intrusive luxation
Displacement of the tooth into the alveolar bone. This injury is accompanied by comminution or fracture of the alveolar socket.

Dislodged Teeth
Injuries to the mouth can cause teeth to be pushed back into their sockets. Your endodontist or general dentist may reposition and stabilize your tooth. Root canal treatment is usually started within a few weeks of the injury and a medication, such as calcium hydroxide, will be placed inside the tooth. Eventually, a permanent root canal filling will be implanted.
Sometimes a tooth may be pushed partially out of the socket. Again, your endodontist or general dentist may reposition and stabilize your tooth. If the pulp remains healthy, then no other treatment is necessary. Yet, if the pulp becomes damaged or infected, root canal treatment will be required.

Avulsed Teeth
Avulsion
The tooth is completely displaced out of its socket. Clinically the socket is found empty or filled with a coagulum.
If an injury causes a tooth to be completely knocked out of your mouth, it is important that you are treated immediately! If this happens to you, keep the tooth moist. If possible, put it back into the socket. A tooth can be saved if it remains moist. You can even put the tooth in milk or a glass of water (add a pinch of salt.) Your Endodontist may start root canal treatment based upon the stage of root development. The length of time the tooth was out of your mouth and the way the tooth was stored, may influence the type of treatment you receive.
Injuries in children
An injured immature tooth may need one of the following procedures to improve the chances of saving the tooth:

Apexogenesis
This procedure encourages the root to continue development as the pulp is healed. Soft tissue is covered with medication to encourage growth. The tip of the root (apex) will continue to close as the child gets older. In turn, the walls of the root canal will thicken. If the pulp heals, no additional treatment will be necessary. The more mature the root becomes, the better the chance to save the tooth.

Apexification
In this case, the unhealthy pulp is removed. The doctors place medication into the root to help a hard tissue form near the root tip. This hardened tissue provides a barrier for the root canal filling. At this point, the root canal walls will not continue to develop, making the tooth susceptible to fractures. So it is important to have the tooth properly restored by your dentist.