H. LU, B. NGUYEN, and J.M. POWERS, University of Texas Health Science Center at Houston Dental Branch, USA
Objective: Mechanical properties of three commercial
elastomeric impression materials with low and high viscosities were compared. Methods:
Two addition silicone impression materials (Imprint II, 3M ESPE; Flexitime,
Heraeus Kulzer) and one polyether material (Impregum, 3M ESPE) were studied.
Elastic recovery (K) and strain-in-compression (E) were tested according to ISO
4823; tear strength (Ts), tear energy (Te) and tensile strength (TS) were
tested following ASTM D624 (Type T), ASTM D1938 and ASTM D412 (Test Method A),
respectively. Five specimens for each group were made for a total of 30 groups
and 150 specimens. Results: Means (sd) of these properties are listed.
ANOVA showed significant differences. Fisher's PLSD intervals are listed (p=0.05).
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K (%)
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E (%)
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Ts(kg/mm)
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Te (J/m^2)
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TS (MPa)
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FLEXITIME Correct Flow (Light Body)
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99.69 (0.07)
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5.27 (0.09)
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0.034 (0.001)
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510 (30)
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1.9 (0.2)
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FLEXITIME Heavy Tray (Heavy-Body)
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99.86 (0.05)
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1.73 (0.06)
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0.069 (0.008)
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561 (18)
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3.5 (0.3)
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IMPRINT II Garant (Light Body)
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99.75 (0.11)
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3.03 (0.04)
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0.048 (0.002)
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654 (23)
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1.6 (0.1)
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|
IMPRINT II Penta (Heavy-Body)
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99.88 (0.07)
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2.82 (0.14)
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0.096 (0.014)
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985 (29)
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1.9 (0.0)
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|
IMPREGUM GARANT Soft (Light Body)
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99.19 (0.10)
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5.57 (0.21)
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0.049 (0.006)
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464 (36)
|
1.2 (0.2)
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IMPREGUM PENTA Soft (Heavy Body)
|
98.79 (0.18)
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5.75 (0.29)
|
0.065 (0.003)
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668 (16)
|
1.6 (0.2)
|
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Fisher's PLSD
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0.07
|
0.10
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0.005
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16
|
0.1
|
Conclusions: There were statistically significant differences among
those materials. All the products had similar elastic recovery and quite
different other properties. Polyether had higher strain-in-compression and less
tensile strength compared to addition silicone materials. Heavy-body materials
had higher tear properties and tensile strength than light-body, with Flexitime
Heavy Tray had the highest tensile strength and Imprint II Penta had the
highest tear properties. Supported by Dental Consultants, Inc.
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