title: Effect of Diode Laser Irradiation Combined with Topical Fluoride on Enamel Microhardness of Primary Teeth.
abstract: OBJECTIVE
  Laser irradiation has been suggested as an adjunct to traditional caries prevention methods. But little is known about the cariostatic effect of diode laser and most studies available are on permanent teeth.The purpose of the present study was to investigate the effect of diode laser irradiation combined with topical fluoride on enamel surface microhardness.
  
  
  METHODS
  Forty-five primary teeth were used in this in vitro study. The teeth were sectioned to produce 90 slabs. The baseline Vickers microhardness number of each enamel surface was determined. The samples were randomly divided into 3 groups. Group 1: 5% NaF varnish, group 2: NaF varnish+ diode laser at 5 W power and group 3: NaF varnish+ diode laser at 7 W power. Then, the final microhardness number of each surface was again determined. The data were statistically analyzed by repeated measures ANOVA at 0.05 level of significance.
  
  
  RESULTS
  In all 3 groups, microhardness number increased significantly after surface treatment (P<0.05). However, Microhardness change after treatment was not significantly different among groups (P >0.05).
  
  
  CONCLUSIONS
  The combined application of diode laser and topical fluoride varnish on enamel surface did not show any significant additional effect on enamel resistance to caries.
authors.affiliation: Associate Professor, Department of pediatric Dentistry, Faculty of Dentistry, Member of Social Determinants of Oral Health Research Center, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Bahrololoomi
authors.affiliation: Department of Pediatric Dentistry, Faculty of Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Malihe
authors.initials: M
authors.lastname: Lotfian
keywords: Diode laser; Fluoride; Hardness; Primary teeth