DENTAL MATERIALS
a)
b)
Figure 2 Particles identification from element mappingin Filtek Ultimate: a) SiO2; b) ZrO2
Table 2 Filler loading, average of particle size and fractal dimension for filtek ultimate and Filtek Supreme XT
Filtek Ultimate
Filtek Supreme XT
ZrO2 particle percent
(% vol.)
12,612
9,669
SiO2 particle percent
(% vol.)
45,732
48,658
Average SiO2 cluster particle size (µm)
0.26±0.02
0.36±0.02
Average ZrO2 cluster particle size (µm)
0.206±0.003
0.218±0.004
Fractal dimension
1.7365
1.6578
image and the number of boxes that contain
pixels is counted for each grid (boxes containing
pixels correspond to the number of parts or
detail). Data are collected for each box of
every grid (grid size is specified by the user or
calculated automatically). The DB is based on the
calculation of a scaling rule or fractal dimension
using (8),
DB= -lim[log(Nε)/log(ε)] (1)
The count refers to the number of grid boxes that
contained pixels in a box counting scan. Epsilon
is the scale applied to an object. In FracLac,
the scale refers to box size relative to image
size, where image size means the boundary
containing the pixelated part of an image.
32
Results and discussions
In Figure1 the typical microstructures of Filtek
Supreme XT and Filtek Ultimate are given for different
magnifications. Uniform particles distributions are
observed and micro-segregates of silica and zirconia
particles. Using the chemical structure obtained by
EDX measurements of the materials tested, from
the element mapping (for more details see (12) it is
possible to identify the SiO2 and ZrO2 particles using
the ImageJ software (11). Some typical results are
given in Figures 2a, b for Filtek Ultimate. Moreover,
from the ratio between particle area and total image
area, the filler particle content can be calculated in
volume percentages.
STOMA.EDUJ (2015) 2 (1)