Horizontal impaction of bilateral mandibular second premolars with distal inclination: A case report

In the Japanese population, the second premolars are the secondmost- frequently impacted teeth in the mandible, after the third molars. Although some papers have reported on the treatment of impacted mandibular second premolars caused by abnormal tilting of the tooth germ, there has been little information regarding bilateral horizontal impaction with distal inclination. The purpose of the present report is to describe the treatment course of a rare and severe case of an 11-year, 8-month-old girl without any obvious etiologies whose bilateral mandibular second premolars were inclined to the distal direction at approximately 90 degree angles, with the root formation developed to an approximately half length. After extraction of the retained primary molars, traction was performed in the treatment of the affected teeth. The affected premolars had fully erupted and achieved occlusion one year after the beginning of intervention. In conclusion, it was considered that the present case could obtain a successful outcome by limited traction since no clinical anomalies or discomfort was detectable during the one year of retention.