title: The effect of three different rotary instrumentation systems on substance P and calcitonin gene-related peptide expression in human periodontal ligament.
abstract: BACKGROUND
  The purpose of this study was to quantify the effect of three different rotary root canal preparation systems on substance P and calcitonin gene-related peptide expression in healthy human periodontal ligament.
  
  
  METHODS
  Fifty periodontal ligament samples were obtained from healthy premolars in which extraction was indicated for orthodontic reasons. Before extraction, 40 of these premolars were equally divided into four groups, and root canals were prepared using four different systems: the ProTaper Universal rotary system, the RaCe rotary system, the Mtwo rotary system, and the hand instrumentation technique. The remaining 10 healthy premolars that were extracted without treatment served as a negative control group. All periodontal ligament samples were processed, and SP and CGRP were measured by radioimmunoassay.
  
  
  RESULTS
  Greater SP and CGRP expression were found in the ProTaper Universal group followed by the hand instrumentation group, the RaCe, and the Mtwo groups. The lower SP and CGRP values were for the negative control group. The Kruskal-Wallis test showed statistically significant differences between groups (p < 0.0001). Post hoc Least Significant Difference (LSD) tests showed statistically significant differences in SP and CGRP expression between the negative control group and all the other groups except the Mtwo group. Hand instrumentation also showed statistically significant differences with all the other groups, except the ProTaper Universal group. Differences between the three rotary systems were also statistically significant.
  
  
  CONCLUSIONS
  SP and CGRP expression in periodontal ligament increases when teeth are prepared with ProTaper Universal and RaCe rotary instrumentation systems as well as with hand instrumentation. Mtwo maintains SP and CGRP levels.
authors.affiliation: Postgraduate Endodontics Department, School of Dentistry, Pontificia Universidad Javeriana, Bogotá, Colombia. javiercaviedes@gmail.com
authors.forename: Javier
authors.initials: J
authors.lastname: Caviedes-Bucheli
authors.forename: Maria Mercedes
authors.initials: MM
authors.lastname: Azuero-Holguin
authors.forename: Luisa
authors.initials: L
authors.lastname: Gutierrez-Sanchez
authors.forename: Ferelba
authors.initials: F
authors.lastname: Higuerey-Bermudez
authors.forename: Veronica
authors.initials: V
authors.lastname: Pereira-Nava
authors.forename: Nelson
authors.initials: N
authors.lastname: Lombana
authors.forename: Hugo Roberto
authors.initials: HR
authors.lastname: Munoz
mesh_terms: D000293:Adolescent; D000328:Adult; D001641:Bicuspid; D015740:Calcitonin Gene-Related Peptide / Q000096:biosynthesis*; D003762:Dental Instruments / Q000009:adverse effects; D023381:Endpoint Determination / Q000706:statistics & numerical data; D006801:Humans; D020078:Neurogenic Inflammation / Q000209:etiology*; D010485:Periapical Periodontitis / Q000209:etiology; D010513:Periodontal Ligament / Q000378:metabolism*; D018915:Root Canal Preparation / Q000009:adverse effects* / Q000295:instrumentation*; D018709:Statistics, Nonparametric; D013373:Substance P / Q000096:biosynthesis*; D014081:Tooth Extraction; D055815:Young Adult
chemical_list: D013373:Substance P; D015740:Calcitonin Gene-Related Peptide