Effect of ultrasonic vibration and various sealer and cement combinations on titanium post removal

The purpose of this study was to determine the effect of ultrasonic vibrati on on the force required to remove prefabricated posts. Ninety-six extracte d human canines were divided into eight groups, which were prepared and obt urated with gutta-percha and either a eugenol-containing (Roth's 801 Elite) or eugenol-free (AH26) sealer. Titanium #6 Parapost XH posts were cemented with either zinc phosphate or Panavia 21 resin cement. One half of the sam ple was subjected to ultrasonic vibration for 16 min at the post-dentin int erface, whereas the other half received no vibration (controls). Each combi nation of sealer, cement, and vibration status was subjected to tensile loa d to failure using an Instron testing machine. Posts cemented in teeth obtu rated with gutta-percha and AH26 sealer demonstrated significantly greater resistance to dislodgement, compared with teeth obturated with gutta-percha and Both's 801 Elite sealer. There was no statistical difference in retent ion of posts cemented with either zinc phosphate or Panavia 21, regardless of the sealer used. Additionally ultrasonic vibration increased post retent ion for both cements.