title: Comparison of Conventional Syringe, CanalBrush, EndoActivator, Photon-Induced Photoacoustic Streaming, and Manual Instrumentation in Removing Orange-Brown Precipitate: An In Vitro Study.
abstract: OBJECTIVE
  The aim of this in vitro study was to compare the various techniques for removing precipitate formed after irrigation with sodium hypochlorite (NaOCl) and chlorhexidine (CHX).
  
  
  BACKGROUND
  It is still unclear whether different irrigant activation systems can effectively remove precipitate that is firmly attached to the root canal walls.
  
  
  METHODS
  Eighty-two extracted single-rooted human teeth were instrumented by using the ProTaper rotary system. The roots were irrigated with 5% NaOCl and then 2% CHX to form orange-brown precipitate on the root canal walls. The teeth were sectioned longitudinally, and the amount of precipitate on the canal walls was measured under a stereomicroscope at 15 × magnification before the root halves were reassembled. Then, conventional syringe irrigation (CSI), CanalBrush (CB), EndoActivator (EA) system, photon-induced photoacoustic streaming (PIPS), and manual instrumentation (MI) techniques were used to remove the precipitate, during which 5 mL of distilled water was used for 1 min. The amount of precipitate remaining on the canal walls was measured, and the percentage of precipitate removed was calculated. Data were analyzed by using the Kruskal-Wallis and Mann-Whitney U tests (p = 0.05).
  
  
  RESULTS
  All experimental groups contained residual precipitate. The precipitate was more effectively removed in the MI group than in the other groups (p < 0.05). The CB and EA groups showed better removal than the CSI and PIPS groups (p < 0.05), and there were no significant differences in removal between these latter two groups (p > 0.05).
  
  
  CONCLUSIONS
  None of the techniques used was able to completely remove the orange-brown precipitate from the root canal surfaces.
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Bezmialem Vakif University , Istanbul, Turkey .
authors.forename: Mehmet Burak
authors.initials: MB
authors.lastname: Guneser
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Bezmialem Vakif University , Istanbul, Turkey .
authors.forename: Asiye Nur
authors.initials: AN
authors.lastname: Dincer
authors.affiliation: Department of Endodontics, Faculty of Dentistry, Bezmialem Vakif University , Istanbul, Turkey .
authors.forename: Dilara
authors.initials: D
authors.lastname: Arslan
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D002710:Chlorhexidine / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D008855:Microscopy, Electron, Scanning / Q000379:methods; D012388:Root Canal Irrigants / Q000737:chemistry*; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods; D012680:Sensitivity and Specificity; D012973:Sodium Hypochlorite / Q000494:pharmacology; D018709:Statistics, Nonparametric; D013499:Surface Properties / Q000187:drug effects; D013594:Syringes; D014075:Tooth Discoloration / Q000188:drug therapy*
chemical_list: D000900:Anti-Bacterial Agents; D012388:Root Canal Irrigants; D012973:Sodium Hypochlorite; D002710:Chlorhexidine
keywords: CanalBrush; EndoActivator; orange-brown precipitate; photon-initiated photoacoustic streaming; sodium hypochlorite; syringe irrigation