Unusual fracture of a maxillary second premolar.

Root fractures of posterior teeth are rare and occur as a result of severe trauma. This study describes a horizontal root fracture of a maxillary second premolar discovered during routine full-mouth radiographic examination. The tooth was asymptomatic and responded positively to electric pulp testing. The patient had no recollection of a causative event nor was there physical evidence of previous trauma. It is speculated that the fracture was caused when overzealous force was used in seating an overcontoured complete gold crown restoration of an adjacent tooth.