Garrido Angela Delfina Bittencourt, Fonseca Tabajara Sabbag, Alfredo Edson, Silva-Sousa Yara Teresinha Corrêa, Sousa-Neto Manoel D
Faculty of Dentistry, University of Ribeirão Preto, SP, Brazil.
J Endod. 2004 Mar;30(3):173-6. doi: 10.1097/00004770-200403000-00011.
The efficacy of ultrasound, with and without water spray, was evaluated in vitro on the amount of force necessary to dislodge posts cemented with resin or zinc phosphate. Forty-two samples were divided into six groups: groups 1, 2, and 3, posts cemented with zinc phosphate; groups 4, 5, and 6, posts cemented with resin (Panavia F); groups 1 and 4 (controls), no ultrasound; groups 2 and 5, ultrasound without water spray; and groups 3 and 6, ultrasound with water spray. The Instron testing machine was used. Ultrasound without water spray significantly reduced (71%) the force necessary to displace posts cemented with Panavia F (p < 0.01); however, this value was similar to the efficacy of ultrasound with water spray for posts cemented with zinc phosphate (reduction of 75%). We conclude that cooling with ultrasound interferes with the force necessary for post removal, depending on the type of cement used.
