ABSTRACT: 0219

Mechanical Behavior of Bite Registration and Impression Materials

T. RAUCH, J. WATERHOUSE, D.W. BERZINS, S. RAMBHIA, and V.B. DHURU, Marquette University, Milwaukee, WI, USA

Understanding the mechanical behavior of bite registration and impression materials is critical in predicting how they might perform clinically.

Objectives: To measure and compare strain in compression (SC), elastic recovery (ER) and creep compliance (CC) of several commercially available bite registration and impression materials of differing viscosity and type.

Methods: Cylindrical (25-mm x 12.7-mm) specimens of Take 1 Bite [Kerr]-(BR-2), Affinis Precious–heavy body [Coltene-Whaledent]-(HV-2), Affinis Precious–light body [Coltene-Whaledent]-(LT-2), Jet Bite [Coltene-Whaledent]-(BR-3), Impregum Penta Soft–heavy body [3M ESPE]-(HV-3), Impregum Garant Soft–light body [3M ESPE]-(LT-3), and Ramitec Penta Bite [3M ESPE]-(BR-4) were prepared according to ISO Specification 4823:2000. HV-3, LT-3, and BR-4 are polyethers; all others are PVS. SC and ER were measured per ISO 4823 (n=5). For creep compliance (n=3), specimens were loaded to 9.8-Newtons for 10 minutes and then unloaded. Readings were taken at 10 seconds and every 30 seconds during loading. The subsequent recovery was monitored every 30 seconds for another 10 minutes. Creep compliance (CC) was calculated at 10 seconds and 10 minutes after application of the load, and at 30 seconds and 10 minutes after removal of the load. Mean results were compared with ANOVA/Tukey(a=0.05).

Results: The means and standard deviation for each property are listed in the table.

SC (%)

ER (%)

CC (MPa^-1)

Initial

10min

Recovery

20min

BR-2

0.64±0.07-D

99.2±0.4-B

2.72±0.59-B

3.19±0.62-B

0.99±0.58-C

0.94±0.67-C

BR-3

1.03±0.18-CD

99.1±0.6-B

0.44±0.04-B

0.53±0.05-B

0.18±0.03-C

0.16±0.02-C

BR-4

1.25±0.09-CD

98.1±0.3-C

6.51±2.62-A

7.61±2.94-A

4.35±1.80-AB

4.14±1.73-AB

HV-2

1.79±0.10-C

99.8±0.1-A

9.64±0.78-A

10.34±0.70-A

0.85±0.22-C

0.85±0.22-C

HV-3

4.51±0.83-B

98.7±0.1-BC

6.53±0.11-A

7.49±0.18-A

4.43±0.27-AB

4.27±0.25-AB

LT-2

4.91±0.28-B

99.1±0.3-B

9.67±1.89-A

10.32±2.11-A

3.23±0.52-B

3.16±0.51-B

LT-3

6.95±0.62-A

98.7±0.1-BC

8.30±0.22-A

9.22±0.30-A

6.00±0.45-A

5.89±0.45-A

Different letters denote significant (p<0.05) differences exist between materials.

Conclusions: Significant differences in mechanical behavior are apparent in elastomeric materials of varying type, consistency, and clinical use.

Seq #47 - Physical Properties of Elastomers
1:30 PM-2:30 PM, Thursday, April 3, 2008
Hilton Anatole Hotel Trinity I - Exhibit Hall

Back to the Dental Materials 6: Polymer-based Materials - Physical Properties and Performance Program