title: Comparison of hand stainless steel and nickel titanium rotary instrumentation: a clinical study.
abstract: The aim of this study was to compare the effect of hand instruments and rotary nickel titanium Flex-Master files used by eight experienced dentists in private practice on the extent of straightening of curved root canals. In patients, 110 canals were prepared by FlexMaster instruments, and 84 canals were enlarged using hand instruments. After instrumentation, all canals were obturated. Preoperative and postoperative radiographs were taken of each tooth using customized bite blocks. Straightening of the canal curvatures was determined with a computer image analysis program. Preparation time and size of the master apical file were also recorded. The use of FlexMaster instruments resulted in significantly less straightening and a shorter preparation time (p < 0.0001) compared with hand instrumentation. Master apical file sizes were significantly greater for FlexMaster than for hand instruments (p < 0.01). This clinical study indicates that FlexMaster instruments prepared curved canals rapidly and with only minimal straightening.
authors.affiliation: Poliklinik für Zahnerhaltung, University School of Dentistry, Waldeyerstrasse 30, D-48149 Münster, Germany. eschaef@uni-muenster.de
authors.forename: Edgar
authors.initials: E
authors.lastname: Schäfer
authors.forename: Udo
authors.initials: U
authors.lastname: Schulz-Bongert
authors.forename: Gabriel
authors.initials: G
authors.lastname: Tulus
mesh_terms: D016009:Chi-Square Distribution; D003722:Dental Alloys / Q000737:chemistry*; D003786:Dental Pulp Cavity / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D004867:Equipment Design; D006801:Humans; D007091:Image Processing, Computer-Assisted; D009532:Nickel / Q000737:chemistry*; D011859:Radiography; D015203:Reproducibility of Results; D012387:Root Canal Filling Materials / Q000627:therapeutic use; D012388:Root Canal Irrigants / Q000627:therapeutic use; D012389:Root Canal Obturation; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D012399:Rotation; D013193:Stainless Steel / Q000737:chemistry*; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*
chemical_list: D003722:Dental Alloys; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium