title: Low Concentration H(2)O(2)/TiO_N in Office Bleaching: A Randomized Clinical Trial.
abstract: OBJECTIVE
  The purpose of this randomized double-blinded clinical trial was to test the efficacy and tooth sensitivity promoted by the use of an in-office 15% H(2)O(2) bleaching agent containing nanoparticles of TiO_N photocatalyzed with LED/laser light (HP15) and a control of 35% H2O2 (HP35).
  
  
  METHODS
  Forty healthy volunteers, both sexes, aged 18 to 25 yr, were randomly distributed in 2 groups: HP15 (n = 20) was treated in 3 sessions of 48 min each, and HP35 (n = 20) was treated in 3 sessions of 45 min each. The efficacy (E) was evaluated by ΔE values measured via reflectance spectroscopy. The tooth sensitivity (S) was analyzed by visual analog scale (low, average, high, very high). The absolute risk reduction and the number needed to treat index were calculated. The data were analyzed by mixed repeated measures analysis of variance with Bonferroni-correction t test (α = 0.05).
  
  
  RESULTS
  For the efficacy, significant differences were found for number of bleaching sessions (p = .0001; [Formula: see text] = 0.73 and π = 1.000) and for the interaction of number of sessions and bleaching protocols (p = .0001; [Formula: see text] = 0.319 and π = 1.000. The tooth sensitivity level showed significant differences only between the bleaching protocols. Absolute risk reduction calculated was 52% and number needed to treat, 1.92.
  
  
  CONCLUSIONS
  The bleaching agent with the lower concentration (HP15) promoted lower levels of tooth sensitivity and presented greater efficacy compared to the control (HP35) in patients between 18 and 25 yr old. The limitation of short-term evaluation did not provide information about the longevity of the tooth bleaching (Brazilian Clinical Trials Registry Re Bec no. U1111-1150-4466).
authors.affiliation: Department of Restorative Dentistry, Araraquara School of Dentistry, UNESP, Univ Estadual Paulista, Brazil janainabortolatto@hotmail.com.
authors.forename: J F
authors.initials: JF
authors.lastname: Bortolatto
authors.affiliation: NUPEN, Resea.
authors.forename: H
authors.initials: H
authors.lastname: Pretel
authors.affiliation: Trent Center for Biomaterials Research, Departments of Physics and Astronomy and Chemistry, Trent University, Canada.
authors.forename: M C
authors.initials: MC
authors.lastname: Floros
authors.affiliation: Department of Restorative Dentistry, Araraquara School of Dentistry, UNESP, Univ Estadual Paulista, Brazil.
authors.forename: A C C
authors.initials: AC
authors.lastname: Luizzi
authors.affiliation: Department of Restorative Dentistry, Araraquara School of Dentistry, UNESP, Univ Estadual Paulista, Brazil.
authors.forename: A A R
authors.initials: AA
authors.lastname: Dantas
authors.affiliation: School of Dentistry of Santiago, Universidad de Chile, Chile.
authors.forename: E
authors.initials: E
authors.lastname: Fernandez
authors.affiliation: School of Dentistry of Santiago, Universidad de Chile, Chile.
authors.forename: G
authors.initials: G
authors.lastname: Moncada
authors.affiliation: Department of Restorative Dentistry, Araraquara School of Dentistry, UNESP, Univ Estadual Paulista, Brazil.
authors.forename: O B
authors.initials: OB
authors.lastname: de Oliveira
mesh_terms: D000293:Adolescent; D000328:Adult; D003807:Dentin Sensitivity / Q000517:prevention & control; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006861:Hydrogen Peroxide / Q000008:administration & dosage*; D057194:Intention to Treat Analysis; D054023:Lasers, Semiconductor / Q000627:therapeutic use; D008297:Male; D053758:Nanoparticles / Q000737:chemistry; D009584:Nitrogen / Q000008:administration & dosage*; D010147:Pain Measurement / Q000379:methods; D017319:Photosensitizing Agents / Q000008:administration & dosage*; D013053:Spectrophotometry / Q000379:methods; D013997:Time Factors; D014025:Titanium / Q000008:administration & dosage*; D014073:Tooth Bleaching / Q000379:methods*; D058205:Tooth Bleaching Agents / Q000008:administration & dosage; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D017319:Photosensitizing Agents; D058205:Tooth Bleaching Agents; C009495:titanium dioxide; D006861:Hydrogen Peroxide; D014025:Titanium; D009584:Nitrogen
keywords: clinical protocols; dentin sensitivity; hydrogen peroxide; nanotechnology; titanium dioxide; tooth bleaching