| ORIGINAL RESEARCH |
|
| Year : 2018 | Volume
: 10
| Issue : 3 | Page : 143-147 |
|
|
A finite element study on effect of cement type and preparation angle on mandibular molar crown restorations' stresses
Rami M Galal1, Salah A Yossef2, Mawadda Adel Alsairafi3, Tariq Muhammad Alkhashem3
1 Department of Fixed and Removable Prosthodontics, National Research Centre, Cairo; Department of Fixed Prosthodontics, Al Nahda University (NUB), Beni Suef; Department of Fixed Prosthodontics, Al Ahram Canadian University (ACU), Giza, Egypt
2 Department of Crown and Bridge, Faculty of Dental Medicine, Al Azhar University, Cairo, Egypt; Department of Restorative Dentistry, Al-Farabi Dental College, Jeddah, Saudi Arabia
3 Afarabi Dental College, Jeddah, Saudi Arabia
Correspondence Address:
Dr. Rami M Galal
59 4th, Touristic District, 6th of October City, Giza
Egypt
 Source of Support: None, Conflict of Interest: None  | Check |
DOI: 10.4103/jioh.jioh_76_18
|
|
|
Aim: The goal is to assess the efficacy of cement type, preparation angle regarding stresses generated on a crown used for covering mandibular first molar under maximum compressive masticatory force. Materials and Methods: Two three-dimensional (3D) finite element models have been created in the study where molar roots and preparation were modeled by engineering CAD/CAM and crown was 3D scanned. The model components were assembled in ANSYS environment with simplified bone geometry. Four analyses were done on the two models to test cement types (Glass ionomer and resin cement) and preparation angles (10° and 18°). Results: Resin cement showed less von Mises stress by about 4% than the glass ionomer at high preparation angle (18°). With preparation angle of 10°, resin cement showed superior behavior by receiving about 30% less von Mises stress in comparison to glass ionomer. Conclusions: Thin cement layer of 40 μm thickness has no effect on the underneath structures. The E-max crown above resin cement and 18° preparation angle may be better than the same combination with 10° preparation angle for roots and bone. On the other hand, 10° preparation angle reduced the crown stresses dramatically.
|
|
|
|
| [FULL TEXT] [PDF]* |
|
 |
|
