Perioperative Injury of Developing Permanent Tooth in Child with Mixed Dentition

Abstract

A perioperative dental injury is a common anesthesia-related complication. During the mixed dentition phase, primary teeth with resorbed roots as well as permanent teeth with immature roots are unstable, thus more susceptible to injury. In addition, midline diastema, normally observed during this period, may isolate the central incisors and increase their susceptibility to injury.

Herein, we report a 7-year-old girl with lateral luxation of the developing left upper central incisor due to displacement of a biting bite block during emergence from anesthesia. She was referred to our clinic because of impacted mesiodens with midline diastema between the developing upper permanent central incisors. Although the left upper primary lateral incisor was not yet exfoliated, it was unstable because of root resorption. The right upper primary lateral incisor was exfoliated and the upper primary canine was located in proximity to the right central permanent tooth. We extracted the impacted mesiodens under general anesthesia. In addition, the left upper primary lateral incisor was extracted to prevent avulsion during anesthesia, which resulted in left permanent incisor isolation along with midline diastema. Following surgery, the bite block was inserted between the left molar teeth and fixed by taping. However, during emergence from anesthesia, the bite block was accidentally displaced to the anterior position by tongue movement, and the isolated left upper central incisor was injured and displaced labially due to biting force. The patient was then immediately treated using manual repositioning and fixation for 4 months. At an examination conducted 1 year 4 months after injury, the post-operative course was shown to be uneventful.

To prevent perioperative tooth injury during the mixed dentition phase, preoperative assessment should include detection of tooth instability associated with short roots as well as tooth isolation due to a combination of midline diastema and loss of adjacent primary incisors.