title: Radiopacity of 28 Composite Resins for Teeth Restorations.
abstract: OBJECTIVE
  Radiopacity is a fundamental requisite to check marginal adaptation of restorations. Our objective was to assess the radiopacity of 28 brands of light-cured composite resins and compare their radiopacity with that of enamel, dentin, and aluminum of equivalent thickness.
  
  
  METHODS
  Composite resin disks (0.2, 0.5, and 1 mm) were radiographed by the digital method, together with an aluminum penetrometer and a human tooth equivalent tooth section. The degree of radiopacity of each image was quantified using digital image processing. Wilcoxon nonparametric test was used for comparison of the mean thickness of each material.
  
  
  RESULTS
  All of the materials tested had an equal or greater radiopacity than that of aluminum of equivalent thickness. Similar results for enamel were found with the exception of Durafill, which was less radiopaque than enamel (p < 0.05). All the specimens were more radiopaque than dentin, except for P90 (which was equally radiopaque) and Durafill (which was less radiopaque). The thickness of the specimens may influence the similarity to the enamel's radiopacity. All of the composite resins comply with specification #27 of the American Dental Association. The radiopacity of Amelogen Plus, Aph, Brilhiante, Charisma, Concept Advanced, Evolux X, Exthet X, Inten S, Llis, Master Fill, Natural Look, Opallis, P60, Tetric, Tph, Z100, and Z250 was significantly higher than that of enamel (p < 0.05).
  
  
  CONCLUSIONS
  With these composites, it is possible to observe the boundaries between restoration and tooth structure, thus allowing clinicians to establish the presence of microleakage or restoration gap.
  
  
  CONCLUSIONS
  Suitable radiopacity is an essential requisite for good-quality esthetic restorative materials. We demonstrate that only some composites have the sufficient radiopacity to observe the boundaries between restoration and tooth structure, which is the main cause of restoration failure.
authors.affiliation: Professor, Department of Oral Pathology, Oral Diagnosis and Oral Radiology, Sao Leopoldo Mandic Research Center, Sao Paulo, Brazil, Phone: +551136735270, e-mail: ricardoraitz@ig.com.br.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Raitz
authors.affiliation: Department of Radiology, School of Dentistry, Braz Cubas University, Mogi das Cruzes, Sao Paulo, Brazil.
authors.forename: Patrizia Dubinskas
authors.initials: PD
authors.lastname: Moruzzi
authors.affiliation: Department of Restorative Dentistry, School of Dentistry University of Sao Paulo (FOUSP), Sao Paulo, Brazil.
authors.forename: Glauco
authors.initials: G
authors.lastname: Vieira
authors.affiliation: Department of Stomatology, School of Dentistry, University of Sao Paulo (FOUSP), Sao Paulo, Brazil.
authors.forename: Marlene
authors.initials: M
authors.lastname: Fenyo-Pereira
mesh_terms: D003188:Composite Resins; D003764:Dental Materials; D019232:Dental Restoration Failure; D003793:Dental Restoration, Permanent; D004954:Esthetics; D006801:Humans; D008422:Materials Testing; D011859:Radiography
chemical_list: D003188:Composite Resins; D003764:Dental Materials
keywords: Composite resins; Digital radiography; Image processing.