Accidents d'évolution des dents de sagesse

Accident occasionned by wisdom teeth are frequent in our practice, and mostly due to infection. Achievement of third molar growth needs several factors : a normal tooth bud which evolution will be tutored by the second molar in order to be situated on the right place in the posterior aspect of mandibular arch. Lack of growth of the mandible in an anteroposterior direction, lack of space in the arch, developmental abnormality in the positioning of the tooth germ or an aberrant path of eruption, cause an impaction or a partial eruption. The crown appears to be partially covered by a gum flap, which inflammation causes the most common complication : an acute péricoronaritis, which main symptoms are : pain, limitation of jaw movements, and fever. If it is mis-treated, an abcess can spread in the oropharyngeal area ant threatens the airways. Subacute complications are sinusitis, osteitis are caused by a long-term evolution and favorised by a treatment which neglected the cause of infection. Mecanical complications are also frequent : third molars may be responsible for the destruction of the crown of the second molar, to create an area of weackness in angular fractures. Multiplication of X rays permit to discover quiescent impacted teeth wich are surrounded by important dentigerous cysts, which histologic analysis is mandatory in order to eliminate an ameloblastoma. Treatment of these complications include the treatment of the acute pathology without forget the treatment of the responsible tooth.