title: Evaluation of success rate of endodontic treatment performed by students with stainless-steel K-files and nickel-titanium hand files.
abstract: A previous study by our group found nickel-titanium (NiTi) 0.02 hand files maintained the original canal shape better than similar stainless-steel K-files (SS-K). Inexperienced dental students used both file types on molar teeth. The purpose of this study was to compare the 1-yr success rate of endodontic treatment of the same teeth used in our previous study. Twelve-month follow-up radiographs were compared with the immediate follow-up radiographs. Both sets of radiographs were taken with the same customized stent. Quantification of osseous changes using digital imaging was used. Thus, a reliable numerical estimation (densitometric ratio) of disease and healing processes could be established. Sixty-seven percent of the patients returned for the 12-month radiographs (19 NiTi vs. 21 SS-K). Immediate postoperative periapical status was found to be similar (p > 0.05). Teeth instrumented with the NiTi files demonstrated a higher mean change in densitometric ratio, compared with SS-K files (p < 0.05). Further tests of success (values: > or =0) and failure (value: < or =0) with the Fisher exact test showed more success (decreasing radiographic density) with NiTi files and more failures (increasing radiographic density) with SS-K type files (p < or = 0.03). This study indicates that maintaining the original canal shape after instrumentation leads to a better prognosis of endodontic treatment.
authors.affiliation: Department of Endodontics, University of North Carolina Schol of Dentistry, Chapel Hill 27599-7450, USA.
authors.forename: M T
authors.initials: MT
authors.lastname: Pettiette
authors.forename: E O
authors.initials: EO
authors.lastname: Delano
authors.forename: M
authors.initials: M
authors.lastname: Trope
mesh_terms: D015502:Absorptiometry, Photon; D003722:Dental Alloys; D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging / Q000473:pathology; D004708:Endodontics / Q000193:education; D004867:Equipment Design; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008963:Molar; D009532:Nickel; D010486:Periapical Tissue / Q000000981:diagnostic imaging / Q000473:pathology; D011379:Prognosis; D011856:Radiographic Image Enhancement; D015203:Reproducibility of Results; D018915:Root Canal Preparation / Q000295:instrumentation*; D012390:Root Canal Therapy; D013193:Stainless Steel; D013223:Statistics as Topic; D013335:Students, Dental; D014025:Titanium; D017211:Treatment Failure; D016896:Treatment Outcome; D014945:Wound Healing
chemical_list: D003722:Dental Alloys; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium