Tooth impaction

An impacted tooth is one that fails to erupt into the dental arch within the expected developmental window. Because impacted teeth do not erupt, they are retained throughout the individual's lifetime unless extracted or exposed surgically. Teeth may become impacted because of adjacent teeth, dense overlying bone, excessive soft tissue or a genetic abnormality. Most often, the cause of impaction is inadequate arch length and space in which to erupt. That is the total length of the alveolar arch is smaller than the tooth arch (the combined mesiodistal width of each tooth). The wisdom teeth (third molars) are frequently impacted because they are the last teeth to erupt in the oral cavity. Mandibular third molars are more commonly impacted than their maxillary counterparts. Some dentists believe that impacted teeth should be removed except, in certain cases, canine teeth: canines may just remain buried and give no further problems, thus not requiring surgical intervention. However, removal of asymptomatic, pathology-free, impacted teeth is not a medical consensus: watchful monitoring may be a more prudent and cost-effective strategy and make the future placement of a dental implant through such impacted tooth a feasible approach. Classifications enable the oral surgeon to determine the difficulty in removal of the impacted tooth. The primary factor determining the difficulty is accessibility, which is determined by adjacent teeth or other structures that impair access or delivery pathway. The majority of classification schemes are based on analysis on a radiograph. The most frequently considered factors are discussed below. Most commonly used classification system with respect to treatment planning. Depending on the angulation the tooth might be classified as: Mesioangular Horizontal Vertical Distoangular Palatal Buccal Lingual This type of classification is based on the amount of impacted tooth that is covered with the mandibular ramus. It is known as the Pell and Gregory classification, classes 1, 2, and 3.