Extrusion - Diagnostic signs

Definition Partial displacement of the tooth out of its alveolar 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. Apart from axial displacement, the tooth will usually have an element of protusion 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.
Visual signs Appears elongated.
Percussion test
Mobility test Excessively mobile.
Sensibility test
Usually lack of response except for teeth with minor displacements. The test is important in assessing risk of healing complications. A positive result to the initial test indicates a reduced risk of later pulp necrosis.

In immature, not fully developed teeth, pulpal revascularization usually occurs. In mature teeth pulp revascularization sometimes occurs.
Radiographic findings Increased periapical ligament space.
Radiographs recommended As a routine: Occlusal, periapical exposure and view from the mesial or distal aspect of the tooth.

Mobility test

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Sensitivity test

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Dental Trauma Guide 2010 - produced in cooperation with the Resource Centre for Rare Oral Diseases and Department of Oral and Maxillo-Facial Surgery
at the University Hospital of Copenhagen - Last edited the 07-01-2014.