title: Percentage exposure of root dentin collagen after application of two irrigation protocols with manual or rotary instrumentation and two methacrylate resin-based sealers.
abstract: OBJECTIVE
  To compare the percentage of collagen exposed in dentin root thirds after two irrigation protocols with manual or rotary instrumentation using two methacrylate resin-based sealers.
  
  
  METHODS
  Forty-eight single-root human teeth were prepared with manual (n = 24) or nickeltitanium ProFile rotary (n = 24) instrumentation, using 5% NaOCl between instruments and 5 ml 17% EDTA as final irrigant or 20% citric acid + 2% chlorhexidine (CHX) between instruments and as the final irrigant. RealSeal or EndoREZ were used as filling materials. One 1-mm slice per third was abraded and stained with Masson's trichrome method. Mean exposed collagen values were obtained in four areas from each section (at 60X magnification) and a complete factorial ANOVA was used to analyze the influence of the study variables. Non-parametric Mann-Whitney's test was used to compare groups. Differences with p < 0.05 were considered significant.
  
  
  RESULTS
  A significantly higher percentage of collagen was exposed in all thirds with the use of the 20% citric acid + 2% CHX protocol with rotary vs manual instrumentation, but percent collagen exposed did not differ as a function of the filling material. After the 5% NaOCl + 17% EDTA protocol, the percentage of collagen exposed did not differ between rotary and manual instrumentation but was higher with the use of RealSeal.
  
  
  CONCLUSIONS
  The highest percentage exposure of collagen was with 20% citric acid + 2% CHX using rotary instrumentation, regardless of the filling material.
authors.forename: Santiago
authors.initials: S
authors.lastname: González-López
authors.forename: Ernesto
authors.initials: E
authors.lastname: Martín-Altuve
authors.forename: Victoria
authors.initials: V
authors.lastname: Bolaños-Carmona
authors.forename: Purificación
authors.initials: P
authors.lastname: Sánchez-Sánchez
authors.forename: Alejandro
authors.initials: A
authors.lastname: Rodríguez-Navarro
mesh_terms: D000134:Acid Etching, Dental; D001391:Azo Compounds; D002710:Chlorhexidine / Q000627:therapeutic use; D019343:Citric Acid / Q000627:therapeutic use; D003094:Collagen / Q000648:ultrastructure*; D004396:Coloring Agents; D003188:Composite Resins / Q000627:therapeutic use; D003722:Dental Alloys / Q000737:chemistry; D003786:Dental Pulp Cavity / Q000648:ultrastructure*; D003804:Dentin / Q000648:ultrastructure*; D004492:Edetic Acid / Q000627:therapeutic use; D004801:Eosine Yellowish-(YS); D006801:Humans; D055115:Light-Curing of Dental Adhesives; D008689:Methacrylates / Q000627:therapeutic use; D008739:Methyl Green; D009532:Nickel / Q000737:chemistry; D012387:Root Canal Filling Materials / Q000627:therapeutic use*; D012388:Root Canal Irrigants / Q000627:therapeutic use*; D018915:Root Canal Preparation / Q000295:instrumentation*; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D014025:Titanium / Q000737:chemistry; D019227:Tooth Apex / Q000648:ultrastructure
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D003188:Composite Resins; D003722:Dental Alloys; C481259:EndoRez; D008689:Methacrylates; C511498:Real Seal composite resin; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; C017768:trichrome stain; C040654:titanium nickelide; D019343:Citric Acid; D009532:Nickel; D008739:Methyl Green; D003094:Collagen; D004492:Edetic Acid; D014025:Titanium; D012973:Sodium Hypochlorite; D002710:Chlorhexidine; D004801:Eosine Yellowish-(YS)