title: Dentinal tubules sealing by means of diode lasers (810 and 980 nm): a preliminary in vitro study.
abstract: OBJECTIVE
  The aim of this study was to evaluate the effect on dentinal surfaces of diode lasers (810 and 980 nm) at different parameters.
  
  
  METHODS
  Twenty-four caries-free human impacted wisdom teeth were used. The crowns were sectioned transversely in order to expose the dentin. The smear layer was removed by a 1 min application of ethylenediaminetetraacetic acid (EDTA). Each surface was divided into four quadrants irradiated at a different output power setting for each kind of laser: 0.8, 1, 1.6, and 2 W (energy densities: 2547, 3184, 5092, and 6366 J/cm(2), irradiation speed 1 mm/sec; optical fiber diameter: 200 μm; continuous and noncontact mode). Half of the samples were stained with a graphite paste. All specimens were sent for scanning electron microscopic (SEM) analysis. Pulp temperature increases in additional 20 teeth were measured by a thermocouple.
  
  
  RESULTS
  Diode laser irradiations at 0.8 and 1 W led to occlusion or narrowing of dentin tubules without provoking fissures or cracks. The application of graphite paste increased the thermal effects in dentin. Measurements of pulp temperature showed that irradiations at 0.8 and 1 W for a period of 10 sec in continuous mode increased pulp temperature (T ≤2°C).
  
  
  CONCLUSIONS
  Diode lasers (810 and 980 nm) used at 0.8 and 1 W for 10 sec in continuous mode were able to seal the dentin tubules. These parameters can be considered harmless for pulp vitality, and may be effective in the treatment of dentinal hypersensitivity.
authors.affiliation: Department of Dental Sciences, Faculty of Medicine, University of Liège , Quai Godfroid Kurth, Liège, Belgium. m18m94@hotmail.com
authors.forename: Monica
authors.initials: M
authors.lastname: Umana
authors.forename: Daniel
authors.initials: D
authors.lastname: Heysselaer
authors.forename: Marc
authors.initials: M
authors.lastname: Tielemans
authors.forename: Philippe
authors.initials: P
authors.lastname: Compere
authors.forename: Toni
authors.initials: T
authors.lastname: Zeinoun
authors.forename: Samir
authors.initials: S
authors.lastname: Nammour
mesh_terms: D000293:Adolescent; D000328:Adult; D003804:Dentin / Q000528:radiation effects*; D003807:Dentin Sensitivity / Q000532:radiotherapy; D006801:Humans; D066298:In Vitro Techniques; D054023:Lasers, Semiconductor / Q000627:therapeutic use*