title: Cutting efficiency of nickel-titanium rotary and reciprocating instruments after prolonged use.
abstract: The aim of the present study was to compare the cutting efficiency of Twisted File instruments used in continuous rotation or TF Adaptive motion and evaluate if prolonged use significantly affected their cutting ability. 20 new NiTi instruments were used in the present study (TF tip size 35, 0.06 taper; Sybron-Endo, Orange, CA, USA), divided into 2 subgroups of 10 instruments each, depending on which movement was selected on the endodontic motor. Group 1: TF instruments were activated using the program TF continuous rotation at 500 rpm and torque set at 2 N; Group 2: TF instruments were activated using the reciprocating TF Adaptive motion. Cutting efficiency was tested in a device developed to test the cutting ability of endodontic instruments. Each instrument cut 10 plastic blocks (10 uses) and the length of the surface cut in a plastic block after 1 min was measured in a computerized program with a precision of 0.1 mm. Maximum penetration depth was calculated after 1 use and after 10 uses, and mean and standard deviation (SD) of each group was calculated. Data were statistically analyzed with a one-way ANOVA test (P < 0.05). TF instruments used in continuous rotation (Group 1) cut a mean depth of 10.4 mm (SD = 0.6 mm) after the first use and 10.1 mm (SD 1.1 mm) after 10 uses, while TF instruments used with the Adaptive motion cut a mean depth of 9.9 mm (SD = 0.7 mm) after the first use and 9.6 mm (SD = 0.9 mm) after 10 uses. There was no statistically significant difference between the two groups investigated (P > 0.05) nor between instruments after 1 or 10 uses. In conclusion, the TFA motion showed a lateral cutting ability similar to continuous rotation and all tested instruments exhibited the same cutting ability after prolonged use.
authors.affiliation: Department of Endodontics, "Sapienza" University of Rome, Via Tommaso Salvini, 57 - 00197, Rome, Italy.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Gambarini
authors.affiliation: Department of Endodontics, "Sapienza" University of Rome, Via Tommaso Salvini, 57 - 00197, Rome, Italy.
authors.forename: Alessio
authors.initials: A
authors.lastname: Giansiracusa Rubini
authors.affiliation: University of Tor Vergata, Rome, Italy.
authors.forename: Giampaolo
authors.initials: G
authors.lastname: Sannino
authors.affiliation: Department of Endodontics, "Sapienza" University of Rome, Via Tommaso Salvini, 57 - 00197, Rome, Italy.
authors.forename: Gianni
authors.initials: G
authors.lastname: Di Giorgio
authors.affiliation: Department of Endodontics, "Sapienza" University of Rome, Via Tommaso Salvini, 57 - 00197, Rome, Italy.
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Di Giorgio
authors.affiliation: Universidade Paranaense UNIPAR, Cascavel, Brazil.
authors.forename: Lucila
authors.initials: L
authors.lastname: Piasecki
authors.affiliation: Department of Restorative Dental Science, College of Dentistry, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Dina
authors.initials: D
authors.lastname: Al-Sudani
authors.affiliation: Department of Endodontics, "Sapienza" University of Rome, Via Tommaso Salvini, 57 - 00197, Rome, Italy. endo@gianlucaplotino.com.
authors.forename: Gianluca
authors.initials: G
authors.lastname: Plotino
authors.affiliation: Department of Endodontics, "Sapienza" University of Rome, Via Tommaso Salvini, 57 - 00197, Rome, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Testarelli
mesh_terms: D003762:Dental Instruments; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008422:Materials Testing; D009532:Nickel / Q000737:chemistry*; D012399:Rotation; D013314:Stress, Mechanical; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*; D019415:Torque
chemical_list: C040654:titanium nickelide; D009532:Nickel; D014025:Titanium
keywords: Cutting efficiency; Cutting test; NiTi instruments; Reciprocation; Rotation