title: Comparative evaluation among different materials to replace soft tissue in oral radiology studies.
abstract: OBJECTIVE
  The aim of this study was to establish which materials afford better simulation of soft tissues in Oral Radiology studies.
  
  
  METHODS
  The sample was composed of four materials in eleven different thicknesses to simulate the soft tissues of the face. The mean values of the relative amounts of radiographic contrast of the materials were determined and compared to a gold standard value, which was obtained from 20 patients who were referred to have periapical radiographs taken of the left mandibular molars. Data were subjected to statistical analysis with Dunnett's test (p<0.05).
  
  
  RESULTS
  The mean value of the relative amounts of contrast encountered in the patients was 0.47, with a range between 0.36 and 0.64 for all 44 material/thickness combinations. The majority of the tested materials showed values close to those of the patients' tissues, without statistically significant differences among them. The values of only three materials/thickness combinations differed statistically from those of the patients' tissues.
  
  
  CONCLUSIONS
  Based on the results of the present study, it may be concluded that except for utility wax (4 mm and 8 mm) and water (4 mm), all materials tested at different thickness could be used as soft tissue substitute materials in Oral Radiology studies.
authors.affiliation: Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas, Piracicaba, SP, Brazil. caldasmaria@hotmail.com
authors.forename: Maria de Paula
authors.initials: Mde P
authors.lastname: Caldas
authors.forename: Flávia Maria de Moraes
authors.initials: FM
authors.lastname: Ramos-Perez
authors.forename: Solange Maria
authors.initials: SM
authors.lastname: de Almeida
authors.forename: Francisco
authors.initials: F
authors.lastname: Haiter-Neto
mesh_terms: D015502:Absorptiometry, Photon; D000180:Acrylic Resins / Q000737:chemistry; D001672:Biocompatible Materials / Q000737:chemistry*; D004867:Equipment Design; D006801:Humans; D008334:Mandible / Q000000981:diagnostic imaging; D008963:Molar / Q000000981:diagnostic imaging; D009061:Mouth Mucosa / Q000000981:diagnostic imaging*; D019047:Phantoms, Imaging; D019904:Polymethyl Methacrylate / Q000737:chemistry; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement; D016300:Radiography, Bitewing; D013499:Surface Properties; D014867:Water / Q000737:chemistry; D014885:Waxes / Q000737:chemistry; D014934:Wood / Q000737:chemistry
chemical_list: D000180:Acrylic Resins; D001672:Biocompatible Materials; D014885:Waxes; D014867:Water; D019904:Polymethyl Methacrylate