Biomedical Engineering Reference
In-Depth Information
Fig. 5.12
(
a
) Schematic illustration of a human tooth; (
b
) the AFM image of the longitudinal
section of tooth enamel after being etched with 0.001 M citric acid solution for 1 min
Fig. 5.13
SEM image of the diamond tip for nanoscratching
In order to investigate the effect of HA crystallites' orientation on the wear
behavior of tooth enamel, we made the scratches along the parallel and vertical
directions to the axis of the enamel rod on the longitudinal section of tooth enamel.
Figure
5.14
shows the SEM images and the friction force versus normal load curves
of the scratches along the vertical and parallel directions to the enamel rod's axis
[
18
]. When the scratch was performed along the vertical direction to the axis of the
enamel rod (left), more surface debris was formed than when it was performed
along the parallel direction of the axis to the enamel rod (right), especially at high
loads [
14
,
19
]. However, with the increase in the normal load, the friction forces
