Preliminary investigation of ultrasonic root end preparation.

Recently, an ultrasonic instrument intended for root end preparation during periapical surgery has become commercially available. This study evaluated root end preparations in 30 extracted human teeth, comparing those prepared with ultrasonic instrumentation to teeth prepared in a traditional manner with a microhandpiece and to teeth prepared using a combination of the microhandpiece and the ultrasonic instrument. Specimens were evaluated for size of preparation, preparation debridement, and time required for preparation. Preparations with the ultrasonic device were found to be significantly smaller than the other techniques evaluated. Traditional and combined techniques resulted in greater debridement under the conditions of the study, and only the combined technique demonstrated an increase in time required for preparation. Ultrasonic instrumentation may provide significant advantages in the treatment of deeply fluted roots when an isthmus is present by reducing the risk of root perforation.