title: Microbiological assessment of root canals following use of rotary and manual instruments in primary molars.
abstract: OBJECTIVE
  To assess the microflora of root canals in primary molars following use of rotary NiTi files and conventional hand NiTi and stainless steel files.
  
  
  METHODS
  This randomized clinical trial consisted of a total of 60 first and second primary molars requiring root canal treatment, who were selected from children aged 5-9 years. Based on type of root canal instrumentation, the teeth were randomly assigned to three groups of twenty teeth each; Group A: Rotary NiTi files, Group B: Hand NiTi files and Group C: Hand stainless steel files. Following administration of local anesthesia, isolation with rubber dam was carried out. For the purpose of instrumentation and sampling, the palatal canal of maxillary molars and the distal canal of mandibular molars were selected. Prior to sampling, the orifices of other canals in these teeth were sealed, so as to prevent any contamination. Instrumentation was carried out in each group using respective instruments along with intermittent saline irrigation. Root canal samples were obtained both before and after instrumentation, using sterile absorbent paper points and transferred to a sterile vial with transport fluid. Serial dilutions were prepared and cultured on suitable agar media. Both aerobic and anaerobic microbial counts were made. Data obtained was subjected to statistical analysis using Wilcoxon signed rank test and one-way Analysis of variance.
  
  
  RESULTS
  In all three groups, there was a significant reduction in both aerobic and anaerobic mean microbial count following root canal instrumentation. (p < 0.001).
  
  
  CONCLUSIONS
  Rotary NiTi files were as efficient as conventional hand instruments in significantly reducing the root canal microflora.
authors.forename: Priya
authors.initials: P
authors.lastname: Subramaniam
authors.forename: T A
authors.initials: TA
authors.lastname: Tabrez
authors.forename: K L Girish
authors.initials: KL
authors.lastname: Babu
mesh_terms: D001420:Bacteria, Aerobic / Q000302:isolation & purification; D001421:Bacteria, Anaerobic / Q000302:isolation & purification; D058491:Bacterial Load; D001431:Bacteriological Techniques; D002648:Child; D002675:Child, Preschool; D003722:Dental Alloys / Q000737:chemistry; D003786:Dental Pulp Cavity / Q000382:microbiology*; D003789:Dental Pulp Exposure / Q000628:therapy; D004867:Equipment Design; D006801:Humans; D008963:Molar / Q000382:microbiology*; D009532:Nickel / Q000737:chemistry; D011671:Pulpitis / Q000628:therapy; D012388:Root Canal Irrigants / Q000627:therapeutic use; D018915:Root Canal Preparation / Q000295:instrumentation*; D012965:Sodium Chloride / Q000627:therapeutic use; D013048:Specimen Handling; D013193:Stainless Steel / Q000737:chemistry; D014025:Titanium / Q000737:chemistry; D014094:Tooth, Deciduous / Q000382:microbiology*; D016896:Treatment Outcome
chemical_list: D003722:Dental Alloys; D012388:Root Canal Irrigants; C040654:titanium nickelide; D013193:Stainless Steel; D012965:Sodium Chloride; D009532:Nickel; D014025:Titanium