Comparison of ultrasonic and high-speed bur root-end preparations using bilaterally matched teeth.

By Mehlhaff DS, Marshall JG, Baumgartner JC.

Date: 12/1997
Journal: JOE


•Purpose:   to compare ultrasonic and high- speed bur root-end preparations.

•N=   29 bilaterally matched pairs of teeth from three adult human cadavers – 76 root-end preparations –


1.all surgical procedures were performed with the teeth in the cadavers by one operator

2.Full-thickness flap was reflected

3.In group I ultrasonic preparations were made in 38 roots and filled with amalgam. In group 2 high- speed bur preparations were made in 38 roots and filled with amalgam.

4.Comparisons were made: the size of bony crypt, the minimum depth of root-end filling in a MD and BL direction, the length of the root-end filling along the resected root surface, and the root-end resection bevel angle. 5.Roots were examined visually and radiographically for perforations.

Most highlighted Results: 

  1.None of the root-end preparations resulted in root perforation. The incidence of ultrasonic deviating was 2.6% & All bur preparations were at an acute angle to the long-axis.

2.The amalgam length along the resected root surface was statistically greater for bur preparations.

3.The mean shallowest depth of preparation when measured from a MD view was significantly greater for ultrasonic compared to bur technique

. 4.Overall BL depth for ultrasonic was statistically greater than the bur preparations. mean difference was 0.5 mm.

5.The mean bevel angle overall for bur preparations (35°) was more than double that for the ultrasonic (16°). The difference was statistically significant.

6.The bony crypt size for bur preparations was significantly greater than that for ultrasonic preparations.

Clinical significance: 

  •  Ultrasonic root-end preparations are superior to high speed bur root-end preparations.