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