Abstract
The patterns of stress distribution were similar but the magnitude was different in four types of lesion.
The peak stress was observed at mesial corner and also stresses concentrated at lesion apex.
The compressive stress under load A and the tensile stress under load B were dominant stress.
Under the load, lesion can be increased and harmful to tooth structure unless restored.
References
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Figure 3.
![jkacd-31-359f3.tif](/upload/SynapseXML/0185jkacd/thumb/jkacd-31-359f3.gif)
Figure 4.
![jkacd-31-359f4.tif](/upload/SynapseXML/0185jkacd/thumb/jkacd-31-359f4.gif)
(M1, M2, M3, M4: nodes near mesial point angle, D1, D2, D3, D4: nodes near distal point angle. If the value of one principal stress of an element was positive, the element was determined to be in the tensile condition, if it was negative, the element was determined to be in the compressive condition).
Figure 5.
![jkacd-31-359f5.tif](/upload/SynapseXML/0185jkacd/thumb/jkacd-31-359f5.gif)
Table 1.
Model | Notch | Saucer | Combined | U |
---|---|---|---|---|
Node | 18245 | 18236 | 18434 | 18709 |
Element | 16668 | 16668 | 16780 | 17056 |
Table 2.
Table 3.
Compressive strength of enamel | 277 – 384 |
---|---|
Compressive strength of dentin | 249 – 347 |
Tensile strength of enamel | 10 – 24 |
Tensile strength of dentin | 32 – 103 |
Tensile strength of DEJ | 52 |
Table 4.
Load A | Load B | ||||||||
---|---|---|---|---|---|---|---|---|---|
1st Peak | 2nd Peak | 1st Peak | 2nd Peak | ||||||
MPa | Node | MPa | Node | MPa | Node | MPa | Node | ||
Notch | Max | 12.4 | 6 | 10.9 | 20 | 193* | 1 | 104.3* | 5 |
Min | -558* | 1 | -279* | 13 | 40.2 | 6 | NS | NS | |
Saucer | Max | 14.6 | 1 | 8.8 | 16 | 123.0* | 1 | 55.8* | 13 |
Min | -330.0* | 1 | -203.3 | 13 | NS | NS | NS | NS | |
Combined | Max | 10.0 | M1 | 18.3 | D3 | 195.5* | 1 | 108.3* | 6 |
Min | -606.7* | 1 | -320.7* | 7 | NS | NS | NS | NS | |
U | Max | 17.8 | D3 | 13.9 | M1 | 147.9* | 1 | 71.1* | 7 |
Min | -500.9* | 1 | -268.7* | 13 | NS | NS | NS | NS |
Table 5.
Load A | Load B | ||||||||
---|---|---|---|---|---|---|---|---|---|
1st Peak | 2nd Peak | 1st Peak | 2nd Peak | ||||||
MPa | Node | MPa | Node | MPa | Node | MPa | Node | ||
Notch | Max | 33.7* | 4 | 25.5 | 17 | 104.3* | 13 | NS | NS |
Min | -280.4* | 13 | -58.8 | 18 | 40.2 | 13 | NS | NS | |
Saucer | Max | 30.8 | 3 | 15.2 | 17 | 61.9* | 13 | 53.0* | 16 |
Min | -157.1 | 10 | -98.1 | 16 | 7.8 | 9 | 4.4 | 13 | |
Combined | Max | 36.8 | 17 | 14.7 | 6 | 108.3* | 9 | 42.0* | 19 |
Min | -317.7* | 1 | -44.2 | 19 | 41.1 | 9 | NS | NS | |
U | Max | 36.01 | 19 | 11.3 | 6 | 100.7* | 15 | 76.6* | 9 |
Min | -240.5 | 10 | -207.3 | 15 | 22.7 | 9 | 2.7 | 15 |