title: Root surfaces after ultrasonic instrumentation with a polishing fluid.
abstract: OBJECTIVE
  The recently introduced Vector system is recommended to be used in conjunction with a polishing fluid containing hydroxylapatite granules (<10 Microm). The aim of the present study was to assess morphologic alterations of the root surface after ultrasonic treatment with the polishing fluid.
  
  
  METHODS
  Cementum of 30 freshly extracted human teeth was removed to a level of 4 mm below the cementoenamel junction. Surfaces were root-planed and conditioned with citric acid to remove the smear layer. Teeth were divided into 5 groups, with group 1 as the untreated control. Group 2 was solely treated with the ultrasonic system. In group 3, the ultrasonic system was used in conjunction with the polishing fluid. Group 4 was treated with a medium-hard toothbrush and the polishing fluid. Group 5 was treated only with the toothbrush. Specimens were evaluated by both light and scanning electron microscopy.
  
  
  RESULTS
  Dentinal tubules were not covered by a smear layer in the control group, whereas in group 2, a smear layer could be observed in some specimens. In group 3 dentinal tubules were always covered by a layer consisting of granules of about 2 Microm. In group 4 all samples showed a layer containing granules of about 5 Microm, and in group 5 a thin smear layer could be observed.
  
  
  CONCLUSIONS
  The use of a polishing fluid containing hydroxylapatite granules during treatment of the root surface results in a granular layer covering the dentinal tubules. This layer may reduce hypersensitivity after ultrasonic subgingival scaling.
authors.affiliation: Department of Periodontology, Operative and Preventive Dentistry, University Dental Clinic Bonn, Bonn, Germany. andreas.braun@uni-bonn.de
authors.forename: Andreas
authors.initials: A
authors.lastname: Braun
authors.forename: Anna
authors.initials: A
authors.lastname: Cichocka
authors.forename: Enas
authors.initials: E
authors.lastname: Semaan
authors.forename: Felix
authors.initials: F
authors.lastname: Krause
authors.forename: Søren
authors.initials: S
authors.lastname: Jepsen
authors.forename: Matthias
authors.initials: M
authors.lastname: Frentzen
mesh_terms: D001672:Biocompatible Materials / Q000627:therapeutic use; D003802:Dentifrices / Q000737:chemistry*; D003804:Dentin / Q000648:ultrastructure*; D003807:Dentin Sensitivity / Q000517:prevention & control; D017886:Durapatite / Q000627:therapeutic use; D006801:Humans; D016745:Root Planing / Q000009:adverse effects; D016369:Smear Layer; D018709:Statistics, Nonparametric; D013499:Surface Properties; D014092:Tooth Root / Q000648:ultrastructure*; D014464:Ultrasonic Therapy / Q000379:methods*