title: In vitro wear of primary and permanent enamel. Simultaneous erosion and abrasion.
abstract: OBJECTIVE
  To evaluate the wear differences between primary and permanent enamel caused by the association of abrasion and erosion.
  
  
  METHODS
  Fragments of 40 human teeth (20 primary and 20 permanent) were cast in acrylic rings, polished to expose a flat enamel area, and evaluated with a 3D profiler. Antagonists were made from primary and permanent molars. The specimens were distributed into four groups (n = 10) according to type of substrate and slurry (neutral and acidic), and cycled 100,000 times in the OHSU oral wear simulator. Specimens were cleaned and re-profiled. Volume loss and maximum depth were determined on the polished specimens. Data were submitted to ANOVA and Tukey's test. The area of the wear facet on the antagonist was measured.
  
  
  RESULTS
  Primary enamel showed more wear than permanent enamel, regardless of the slurry type. The acidic environment increased the wear rate compared to the neutral slurry. The association of abrasion and erosion increased the wear rate for the primary teeth only. There was no significant difference among groups for cusp wear and no correlation between cusp wear and the enamel wear.
authors.affiliation: Department of Restorative Dentistry, Dental Material Area, Piracicaba Dental School, UNICAMP, Av. Limeira, 901, CEP 13414-018, Piracicaba, SP, Brazil. giselefop@yahoo.com
authors.forename: Gisele Maria
authors.initials: GM
authors.lastname: Correr
authors.forename: Roberta Caroline Bruschi
authors.initials: RC
authors.lastname: Alonso
authors.forename: Simonides
authors.initials: S
authors.lastname: Consani
authors.forename: Regina Maria
authors.initials: RM
authors.lastname: Puppin-Rontani
authors.forename: Jack L
authors.initials: JL
authors.lastname: Ferracane
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D019343:Citric Acid / Q000494:pharmacology; D003743:Dental Enamel / Q000473:pathology*; D004198:Disease Susceptibility; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D021621:Imaging, Three-Dimensional; D008297:Male; D008855:Microscopy, Electron, Scanning; D019904:Polymethyl Methacrylate / Q000737:chemistry; D014072:Tooth Abrasion / Q000209:etiology / Q000473:pathology*; D014077:Tooth Erosion / Q000209:etiology / Q000473:pathology*; D014094:Tooth, Deciduous / Q000473:pathology*; D014867:Water / Q000494:pharmacology
chemical_list: D014867:Water; D019343:Citric Acid; D019904:Polymethyl Methacrylate