title: Comparative radiopacity of six current adhesive systems.
abstract: BACKGROUND
  The radiopacity of contemporary adhesive systems has been mentioned as the indication for replacement of restorations due to misinterpretation of radiographic images.
  
  
  OBJECTIVE
  This study aimed to evaluate the radiopacity of contemporary bonding agents and to compare their radiodensities with those of enamel and dentin.
  
  
  METHODS
  To measure the radiopacity, eight specimens were fabricated from Clearfil SE Bond (CF), Xeno V (XE), Adper SE Bond (ASE), Magic Bond (MB), Single Bond 2 (SB), Scotchbond Multipurpose (SM), and gutta-percha (positive control). The optical densities of enamel, dentin, the bonding agents, gutta-percha, and an aluminium (Al) step wedge were obtained from radiographic images using image analysis software.
  
  
  METHODS
  The radiographic density data were analyzed statistically by analysis of variance and Tukey's test (α =0.05).
  
  
  RESULTS
  Significant differences were found between ASE and all other groups tested and between XE and CF. No statistical difference was observed between the radiodensity of 1 mm of Al and 1 mm of dentin, between 2 mm of Al and enamel, and between 5 mm of Al and gutta-percha. Five of the six adhesive resins had radiopacity values that fell below the value for dentin, whereas the radiopacity of ASE adhesive was greater than that of dentin but below that of enamel.
  
  
  CONCLUSIONS
  This investigation demonstrates that only ASE presented a radiopacity within the values of dentin and enamel. CF, XE, MB, SB, and SM adhesives are all radiolucent and require alterations to their composition to facilitate their detection by means of radiographic images.
authors.affiliation: Department of Restorative Dentistry, Cesmac University Center, Maceió, Alagoas, Brazil.
authors.forename: Isabel Cristina Celerino
authors.initials: IC
authors.lastname: de Moraes Porto
authors.affiliation: Department of Restorative Dentistry, Cesmac University Center, Maceió, Alagoas, Brazil.
authors.forename: Naira Cândido
authors.initials: NC
authors.lastname: Honório
authors.affiliation: Department of Restorative Dentistry, Cesmac University Center, Maceió, Alagoas, Brazil.
authors.forename: Dayse Annie Nicácio
authors.initials: DA
authors.lastname: Amorim
authors.affiliation: Department of Oral Radiology, Cesmac University Center, Maceió, Alagoas, Brazil.
authors.forename: Aurea Valéria
authors.initials: AV
authors.lastname: de Melo Franco
authors.affiliation: Department of Restorative Dentistry, Cesmac University Center, Maceió, Alagoas, Brazil.
authors.forename: Luiz Alexandre Moura
authors.initials: LA
authors.lastname: Penteado
authors.affiliation: Faculty of Dentistry, School of Dentistry, International Medical University, Kuala Lumpur, Malaysia.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Parolia
keywords: Densitometry; dentin-bonding agents; radiography