IADR Abstract Archives
Mechanical Properties of Experimental Dental Composites of New Diluent Monomers
Current dental composites contain significant amount of TEDGMA as a diluent monomer. Such a monomer may increase water sorption of the composites and may have biological side effects when leaching out. Objective: To formulate and test experimental dental composites containing less hydrophilic and less viscose monomers EBPADMA and HDDMA. Methods: ethoxylated bisphenol-A dimethacrylate (EBPADMA) and hexanediol dimethacrylate (HDDMA) were provided by Esstech Inc. (Essington, PA, USA). One control (BisGMA/TEGDMA=60/40) and nine experimental composites with different BisGMA/TEGDMA/EBPADMA/HDDMA ratios have been formulated. All materials contain 65 wt% fluoroaluminosilicate filler (0.9 mm, Caulk/Densply). Rectangular specimens (2x2x25, n=10) of each material were fabricated using brass molds and light cured in three segments (40s each). The specimens were polished and stored in distilled water at 37oC for 24 hours. Flexure strength tests were conducted on an Instron universal testing machine with a crosshead speed of 1 mm/min. The data were analyzed use ANOVA and Tukey test (a=0.05). Results:
|
Monomer Composition (Wt%) |
Control |
Exp 1 |
Exp 2 |
Exp 3 |
Exp 4 |
Exp 5 |
Exp 6 |
Exp 7 |
Exp 8 |
Exp 9 |
|
BisGMA |
60 |
60 |
60 |
50 |
50 |
50 |
40 |
40 |
40 |
40 |
|
TEGDMA |
40 |
|
|
30 |
|
|
20 |
|
|
|
|
EBPADMA |
|
10 |
20 |
20 |
30 |
20 |
40 |
30 |
40 |
50 |
|
HDDMA |
|
30 |
20 |
|
20 |
30 |
|
30 |
20 |
10 |
|
FS (MPa) |
101.6 |
80.1 |
91.3 |
89.8 |
80.9 |
90.9 |
89.4 |
88.0 |
101.9 |
82.7 |
|
STD (MPa) |
5.9 |
6.8 |
10.2 |
10.0 |
6.9 |
10.2 |
5.7 |
7.7 |
5.5 |
5.7 |
|
Grouping |
A |
B |
A,B |
A,B |
B |
A,B |
A,B |
A,B |
A |
B |
Experimental 8 has the same flexure strength as the control. Experimental 2, 3, 5, 6, and 7 have slightly lower but statistically similar flexure strength as the control. Conclusion: With careful formulation, EBPADMA and HDDMA can replace all TEGDMA and part of BisGMA and produce the dental composites with similar mechanical properties. Supported by the Brown Foundation.