Page 30 - COS-FOD2015

Compend. Oral Sci:vol1(4);2015;21-31

The multicolour indicator in pseudocolour image Two-way ANOVA with post hoc multiple com-
mode illustrates depth of each grooves clearly. parisons tests and One-way ANOVA were em-
The reference plane was determined on the ployed, with the confidence level set at p = 0.01

image before recording the depth of the for statistical significance.
grooves in z-direction as described by McCabe
The mean difference in depth of grooves for
& Carrick 2006 (10). Depth measurements for
each material is displayed in Table 2. Two-way
each groove were taken at each of the three
ANOVA revealed no interaction between type of
reference lines for both master dies and their
impression materials and grooves (p > .01).
correponding impressions. Measurements were
However, there was significant difference for
also taken at 1mm above and 1mm below each
impression materials and grooves. The Dunnett
reference line. The total number of depth meas-
t (2-sided) post hoc test showed that Aquasil
urements for 7 master dies and their corre-
putty/light and Express putty/light exhibited sig-
sponding impression was 9, giving a total of 63
nificantly lower mean difference in depth com-
measurements for each impression material
pared to Impregum medium (control group). For
tested. The mean difference in depth between
multiple comparisons between test groups
the master die and its corresponding impres-
(Games Howell test), significant difference were
sion was computed for analysis. Profiles of all
observed for Express putty/light which recorded
impressions were inverted so that impression of
the lowest mean difference in depth (17.86μm ±
grooves could be readily compared with master
17.84) in the reproduction of U-shaped groove
die.
of 1mm and Impregum heavy/light recorded the
highest mean difference in depth (58.44μm ±
44.19) in the reproduction of V-shaped groove
Results
of 2mm (p < 0.01).
The mean difference in depth between the mas-
One-way ANOVA revealed that there was no
ters dies and its impressions for all grooves
significant difference between all materials in
type were analyzed using a statistical package
the V-shaped groove of 2 mm depth. In the
(SPSS v12, SPSS IBM Corp., Chicago, USA).

Table 2. The mean difference in depth for each material and groove is displayed in the table

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