IADR Abstract Archives
Wear Resistance and Mechanical Properties of Novel Dental Nanocomposites
The objective was to prepare highly aesthetic radiopaque experimental nanocomposites (ENC) from novel nano-sized fillers and study their mechanical properties and wear resistance (WR). Two new types of filler particles were used: (a) non-aggregated and non-agglomerated silica particles, nanomers (NM) 5 or 20nm and (b) loosely bound agglomerates of zirconia-silica nanoclusters (NC) of primary particle size < 50nm). The dimension of the NM and ratio of NM to NC were varied to study their effect on the properties. Diametral tensile strength (DTS) was measured according to modified ADA Spec 27; WR (
mm/10^5cycles) was measured by modified ACTA method. The table shows the DTS and WR of various experimental formulations. Commercial composites microfill FiltekA110 (A), hybrids Z250 (Z) and TPH spectrum (T) and micro-hybrids EsthetX (E) and Point 4 (P) were studied for comparison|
ENC |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
|
NM (nm) |
- |
5 |
5 |
5 |
20 |
20 |
20 |
|
NM % by wt |
0 |
7.8 |
15.6 |
23.4 |
11.4 |
22.8 |
34.1 |
|
NC % by wt |
100 |
92.1 |
84.4 |
76.6 |
88.6 |
77.2 |
65.9 |
|
WR (sd) |
5.0 (0.6) |
3.6 (0.2) |
2.0 (0.3) |
1.6 (0.2) |
3.4 (0.2) |
3.0 (0.1) |
2.4 (0.6) |
|
DTS (sd) |
84 (6) |
75 (7) |
70 (11) |
73 (6) |
87 (6) |
87 (4) |
---- |
WR of the commercial materials were A 8.9 (0.5), Z 6.2 (0.4), T 12.3 (0.4)), E 9.8 (0.9), P 8.7 (0.3). The DTS were A 59 (2), Z 92 (7), T 75 (10), E 60 (13), P 54 (20). ANOVA analysis showed that at p<0.05 all the aesthetic ENCs had wear resistance that were significantly better than those of the commercial hybrid and microhybrids and microfill tested. The DTS values of most of the ENCs were significantly higher than the microfill and two microhybrids, and were either equivalent to or higher than the hybrids tested.