In vitro wear of primary and permanent enamel. Simultaneous erosion and abrasion.
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.
Correr
Gisele Maria
GM
Department of Restorative Dentistry, Dental Material Area, Piracicaba Dental School, UNICAMP, Av. Limeira, 901, CEP 13414-018, Piracicaba, SP, Brazil. giselefop@yahoo.com
Alonso
Roberta Caroline Bruschi
RC
Consani
Simonides
S
Puppin-Rontani
Regina Maria
RM
Ferracane
Jack L
JL
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
D014867:Water; D019343:Citric Acid; D019904:Polymethyl Methacrylate