Background
Trauma to the teeth may result in fractures, avulsions, or displacements. Injury to primary teeth more often results in displacement of teeth rather than fractures. Maxillary and mandibular incisors are the most commonly displaced primary teeth. [1]
Pathophysiology
A typical cause is a directed force sufficient to overcome the bond between the affected tooth and the periodontal ligament within the cradling alveolar socket. Displacement may be in the form of subluxation, intrusion into the alveolar socket, or extrusion from the socket with tearing of the apical neurovascular bundle. All these forces may lead to pulp necrosis and apical abscess formation. [2]
Etiology
Causes of tooth displacement include the following:
-
Unknown (17%)
-
Altercations (17%)
-
Contact sports (15.9%)
-
Motor vehicle collisions (10.8%)
-
Motorcycle accidents (10.4%)
-
Ice hockey (2.3%)
In children, the most common cause of displacement injuries to primary teeth (up to 44.8%) is a fall while walking or running. [3]
Epidemiology
United States data
Dental displacement is the most common injury to primary dentition. [4]
International data
A study conducted in Sweden showed that approximately 7% of all physical injuries involved the oral cavity. In patients aged 0-19 years, 9% of all injuries involved the oral cavity. More than 50% of physical trauma in child abuse cases occurs in the head and neck region. During the Korean War, 3000 maxillofacial injuries occurred. [5]
Sex- and age-related demographics
Male-to-female ratio is 2-3:1.
Average age of injury is variable. In youths, falls and sporting activities account for the majority of injuries. In the later teenaged years, motor vehicle collisions (MVCs) and assaults account for the majority of injuries.
Prognosis
Morbidity/mortality
Trauma to the teeth is not life threatening; however, associated maxillofacial injuries and fractures can compromise the airway. Morbidity to the teeth may be individualized to primary and permanent teeth.
Almost half of teeth with luxation injuries become necrotic after 3 years.
-
Primary teeth - Failure to continue eruption, color changes, infection, abscess, loss of space in the dental arch, ankylosis, injury to the permanent teeth, abnormal exfoliation
-
Permanent teeth - Color changes, infection, abscess, loss of space in the dental arch, ankylosis, resorption of root structure, abnormal root development [6]
Complications
Complications of tooth displacement include the following:
-
Tooth loss
-
Cosmetic deformity
-
Infection
Patient Education
For excellent patient education resources, visit eMedicineHealth's Oral Health Center. Also, see eMedicineHealth's patient education articles Broken or Knocked-out Teeth and Toothache.
