Mechanical characterization of sclerotic occlusal dentin by nanoindentation and nanoscratch.
OBJECTIVE
To evaluate the mechanical properties of occlusal wear lesions identified as sclerotic.


METHODS
Nanoindentation and nanoscratch techniques have been applied to determine elastic modulus (E), hardness (H) and wear resistance of different types of sclerotic dentin. Nanoscratch testing was applied to evaluate the tribological behavior. Mechanical properties of sclerotic dentin were evaluated together with scanning electron micrographs to show the different degree of tubular occlusion.


RESULTS
The higher the degree of sclerosis, the lower were the measured mechanical properties. The highest values (E = 20 GPa and H = 0.67 GPa) were obtained in normal dentin, and the lowest (E = 11.4 GPa and H = 0.51 GPa) in severe sclerotic lesions. These differences were statistically significant (P<0.05). The groove width in the nanoscratch tests was also higher for moderate or severe sclerosis than for normal dentin.
Martín
Noelia
N
Department of Conservative Dentistry, Complutense University, Madrid, Spain.
García
Alvaro
A
Vera
Vicente
V
Garrido
Miguel Angel
MA
Rodríguez
Jesús
J
D000368:Aged; D003799:Dental Stress Analysis; D003809:Dentin, Secondary / Q000473:pathology* / Q000648:ultrastructure*; D055119:Elastic Modulus; D006244:Hardness; D006801:Humans; D008875:Middle Aged; D036103:Nanotechnology / Q000379:methods; D019217:Tooth Attrition / Q000473:pathology*