Resumen:
INTRODUCTION:
The shaping ability of root canal instruments is determined by a complex interrelationship of parameters such as cross-sectional design and the ability to remove debris and the smear layer. The self-adjusting file (SAF) consists of a hollow, flexible instrument in the form of a compressible, thin-walled, pointed cylinder. The aim of this study was to compare the SAF with the ProTaper rotary file system, evaluating debris and smear layer removal and the presence of bacteria by using microbiological and scanning electron microscopy (SEM) evaluation.
METHODS:
Fifty maxillary premolars were inoculated with Enterococcus faecalis for 30 days and then randomly distributed into 2 groups. Group 1 was prepared with ProTaper rotary instruments and irrigated with 30-gauge side-vented needles. Group 2 was prepared by using the SAF system with continuous irrigation. Bacteriologic samples were taken before and after preparation. All samples were then longitudinally split and analyzed under scanning electron microscopy. The scoring was carried out by 3 blinded evaluators.
RESULTS:
In group 1, 40% of samples had negative cultures with postinstrumentation samples taken with paper points (S2a) an...