19 May 2025 : Laboratory Research
Impact of Margin Type and Material Choice on Stress Distribution in Endocrown Restorations: A 3D Finite Element Study
Kulashekar Reddy Nandalur
ABCEF 1*, Abdulkarim Hussain Alshehri ABEF 1, Hemant Ramesh Chourasia ABCE 2, Mohammed E. Sayed ABEG 1, Khurshid Ahmed Mattoo CDEF 1, Vinod Bandela ACEF 3, Huda Mohammad AlBodham CDEG 4, Ali Y. Alsaeed CDEG 5, Nisreen Nabiel Hassan ACDE 6, Firas K. Alqarawi ACDE 7, Abeer Ali Qahtani CDEG 8, Yaqoub Ahmed Ayyashi BEF 9, Muhannad Ali Masmali BEF 10, Mohamad Assad Aljabri BEF 9, Miad Ali Alasmary CEF 11
DOI: 10.12659/MSM.948308
Med Sci Monit 2025; 31:e948308
Table 4 Standard stress peak levels (Mpa) and their relative risk of cohesive and adhesive failures in the resin cement layer.
| Model | Design features | Material | Cement NX3 stress peak (MPA) | Failure risk | |
|---|---|---|---|---|---|
| Cohesive | Adhesive | ||||
| A | M – Flat ButtPCE – 2 mmOT – 3 mm | Zirconia | 1.778 | 0.0114 | 0.0176 |
| Lithium disilicate | 4.658 | 0.0119 | 0.0183 | ||
| Nanoceramic resin | 0.868 | 0.0164 | 0.0253 | ||
| B | M – Flat ButtPCE – 4 mmOT – 3 mm | Zirconia | 1.222 | 0.0167 | 0.0256 |
| Lithium disilicate | 3.506 | 0.0209 | 0.0322 | ||
| Nanoceramic resin | 0.596 | 0.0235 | 0.0361 | ||
| C | M – 20° bevelPCE – 2 mmOT – 3 mm | Zirconia | 1.675 | 0.0246 | 0.0378 |
| Lithium disilicate | 3.757 | 0.0310 | 0.0477 | ||
| Nanoceramic resin | 0.856 | 0.0322 | 0.0495 | ||
| D | M – 20° bevelPCE – 4 mmOT – 3 mm | Zirconia | 1.089 | 0.0323 | 0.0497 |
| Lithium disilicate | 4.344 | 0.0342 | 0.0526 | ||
| Nanoceramic resin | 0.62 | 0.0344 | 0.0528 | ||
| E | M – ShoulderPCE – 2 mmOT – 3 mm | Zirconia | 1.786 | 0.0644 | 0.0989 |
| Lithium disilicate | 3.344 | 0.0675 | 0.1037 | ||
| Nanoceramic resin | 1.613 | 0.0723 | 0.1111 | ||
| F | M – ShoulderPCE – 4 mmOT – 3 mm | Zirconia | 1.278 | 0.0731 | 0.1123 |
| Lithium disilicate | 3.797 | 0.0836 | 0.1285 | ||
| Nanoceramic resin | 1.681 | 0.0897 | 0.1378 | ||
| M – margin type; PCE – pulp chamber extension; OT – occlusal thickness; CAD – computer-assisted/aided diagnosis. Model descriptions: model A = flat butt margin +2 mm PCE +3 mm OT; model B = flat butt margin +4 mm PCE +3 mm OT; model C = 20° bevel margin +2 mm PCE +3 mm OT; model D = 20° bevel +4 mm PCE +3 mm OT; model E = shoulder margin +2 mm PCE +3 mm OT; model F = shoulder margin +4 mm PCE +3 mm OT. Statistical analysis: cohesive failure risk = stress peak value/tensile strength; adhesive failure risk = stress peak value/adhesive bond strength of the concerned material to dentin. | |||||