The Biomechanical Analusis Of Three-Unit Postetior All-Ceramic Fixed Partial Dentures With Different Materials

Objective: To construct the three-dimensiona finite elemet model of the maxillary postetior fixed partial denture (FPD) with the original DICOM data of spiral CT, investigate the biomechanics characters of the FPD by loading, and and carries on the finite element analysis to three different material's all-ceramic fixed partial denture.Methods:â‘ A macerated human skull was scanned with spiral CT and the original DICOM data were imported into MIMICS software. The three-dimensional geometrical model containing the mandibular second premolar,mandibular first molar, mandibular second molar and the corresponding alveolar bone was constructed. The three-dimensional finite elemet model of the maxillary postetior fixed partial denture was constructed after slotting in three dimensional finite element analysis software ANSYS.â‘¡On the basis of the three-dimensional model of the first Part,we observed the load conditions on pontic of the maxillary FPD and analysed the stress distribution and displacement with a finite element program ANSYS.â‘¢Seting the core crown material of the fixed partial denture is IPS e.max press, In-Ceram Alumina and Zirconia, we analysed the stress distribution and displacement with a finite element program ANSYS.Results:â‘ The establishment three-dimensional finite element model of maxillary postetior all-ceramic fixed partial denture, which was made up of 67331 nodes and 344188 units, included maxilla, teeth and all-ceramic fixed partial denture. Model and modeling had a good geometric similarity. So it had scalability and it could be splitted randomly or extracted a certain part for a separate study.â‘¡According to the FEA analysis after loading on the ponitic, the displacement in gingival margin of lingual surface was most significant , the stress occurred in connective area, and the gingival was more dignificant than occlusal.â‘¢Loading separately to three material's all-ceramic fixed partial denture, the displacement and the stress of Zirconia group's was smaller than other two groups, during the latter two groups differs not in a big way.Conclusion: The method to construct a complex fixed partial denture three-dimensional finite element model is improved by using the MIMCS and ANSYS software which based on the spiral CT. what's more it was easy to apply and calculate.The connective aera was the frailest spot of all- FPD, must be reinforced.The displacement and stress in gingival margin of lingual side was significant than the buccal side.Compared the three kind material of commonly used all-creamic FPD, the Zirconia surpassed IPS e.max press and In-Ceram Alumina group, but the latter two groups had no significant difference. The material of IPS e.max press,In-Ceram Alumina and Zirconia could be used for the postetior fixed partial denture.