title: Does a chitosan-containing dentifrice prevent demineralization around orthodontic brackets?
abstract: OBJECTIVE
  To test the null hypothesis that there is no significant difference between the chitosan-containing and conventional nonfluoridated dentifrices in inhibition of enamel demineralization around orthodontic brackets.
  
  
  METHODS
  Sixteen orthodontic patients who were scheduled to have extraction of four first premolars for orthodontic reasons were divided into two groups after the power of the study was estimated. Patients in the experimental group were instructed to use chitosan-containing dentifrice (AloeDent), and patients in the control group were instructed to use nonfluoridated dentifrice (Sensodyne Mint). After 60 days, the teeth were extracted and longitudinally sectioned. The demineralization was assessed by cross-sectional microhardness. The determinations were made at the bracket edge cementing limits and at occlusal and cervical points, 100 µm and 200 µm away from the edge. In all these positions, indentations were made at depths of 10, 20, 30, 50, 70, and 90 µm from the enamel surface. Analysis of variance (ANOVA) and Tukey test were used for statistical evaluation at P < .05 level.
  
  
  RESULTS
  ANOVA showed statistically significant differences for the factors of dentifrice type, position, and depth (P  =  .000). Statistically significant differences for microhardness values between two tested dentifrices were observed up to 20 µm of depth from the enamel surface (P < .05). Lower microhardness values were found for nonfluoridated dentifrice. Significant microhardness differences were also determined between materials at occlusal and cervical 0 µm positions (P < .05). At these positions, chitosan-containing dentifrice showed lower demineralization than the control.
  
  
  CONCLUSIONS
  Chitosan-containing dentifrice may reduce the enamel decalcification found in patients with poor oral hygiene. The null hypothesis is rejected.
authors.affiliation: Erciyes University, Department of Orthodontics, Kayseri, Turkey. tancanuysal@yahoo.com
authors.forename: Tancan
authors.initials: T
authors.lastname: Uysal
authors.forename: Meltem Derya
authors.initials: MD
authors.lastname: Akkurt
authors.forename: Mihri
authors.initials: M
authors.lastname: Amasyali
authors.forename: Suat
authors.initials: S
authors.lastname: Ozcan
authors.forename: Ahmet
authors.initials: A
authors.lastname: Yagci
authors.forename: Feridun
authors.initials: F
authors.lastname: Basak
authors.forename: Deniz
authors.initials: D
authors.lastname: Sagdic
mesh_terms: D000704:Analysis of Variance; D048271:Chitosan / Q000627:therapeutic use*; D003802:Dentifrices / Q000737:chemistry / Q000627:therapeutic use*; D006244:Hardness; D006801:Humans; D015588:Observer Variation; D016910:Orthodontic Brackets / Q000009:adverse effects*; D018709:Statistics, Nonparametric; D017001:Tooth Demineralization / Q000209:etiology / Q000517:prevention & control*
chemical_list: D003802:Dentifrices; D048271:Chitosan