title: The effects of opaque and clear pit and fissure sealants on infrared laser fluorescence measurements.
abstract: BACKGROUND
  The purpose of placing sealants is to inhibit caries by physical closure of the pits and fissures of teeth. A device named DIAGNOdent is useful in detecting occlusal caries by employing laser fluorescence (LF). However, there are contradictory results in the influence of sealants on LF measurements.
  
  
  OBJECTIVE
  The aim of this study is to investigate the effects of two different types of fissure sealants on LF measurements.
  
  
  METHODS
  In this in vitro study, 86 extracted permanent third molars were divided randomly into two groups and clear or opaque sealant was applied on the occlusal surfaces. Two examiners performed pre- and post-seal fluorescence measurements twice with one week interval by employing DIAGNOdent device. Finally, measured values were evaluated through the statistical paired t-test by means of SPSS 17 software.
  
  
  RESULTS
  The mean value of LF measurements increased significantly due to the application of clear sealant (p= 0.001) while the statistical changes in this measurement was negligible after applying opaque sealant (p= 0.311).
  
  
  CONCLUSIONS
  Clear sealants increase the LF measured values but opaque sealants cause almost no changes. Therefore, DIAGNOdent device is not reliable for detecting caries beneath the clear sealant.
authors.affiliation: Dept. of Pediatric Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Z
authors.initials: Z
authors.lastname: Bahrololoomi
authors.affiliation: Dentist.
authors.forename: M
authors.initials: M
authors.lastname: Khodabakhsh
authors.affiliation: Post Graduate Student in Pediatric Dentistry, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
authors.forename: Y
authors.initials: Y
authors.lastname: Khaksar
keywords: Caries; Laser Fluorescence; Pit and Fissure Sealants