IADR Abstract Archives
3D-FEA of Abutment Type Combinations for Implant Screw-retained Fixed-partial Dentures
Objectives: To evaluate the stress distribution, using Finite Element Analysis (FEA), on different implant components of a mandibular screw-retained fixed partial denture (FPD) situation when using combinations of engaging and non-engaging abutments.
Methods: Patients anatomy was digitized through CBCT and digitally designed dental implants were positioned in the lower right posterior area of teeth #’s 28 (premolar – pm) and 30 (molar – m). Restorative implant components (abutments, screws and FPD) were digitally designed and placed into the implant model. Four implant abutment situations were simulated through FEA: Both engaging abutments (pmE-mE), both non engaging (pmNE-mNE), premolar engaging and molar non-engaging (pmE-mNE), and premolar non-engaging and molar engaging (pmNE-mE). Thirty-five (35) Ncm preload to the screws and 160 N static load at 45-degree angle to the occlusal plane were applied in each group.
Results: The equivalent Von Mises stress was measured on each component. Stress distribution changed among the different configurations and ranged from 632 MPa to 1362 MPa in the implants, and from 581 MPa to 878 MPa with the abutments. The highest values for the implants were found for the NE designs (1146-1362 MPa). The lowest stress on both abutments was measured with the pmE-mNE configuration.
Engaging and non-engaging abutments had different stress distributions on the screw (626-830 MPa). Peak stress areas were located on the upper part of the screws for the non-engaging configuration, and on the lower areas for the engaging abutments. The sum of the stress on both screws decreased in the following order: pmNE-mNE > pmE-mE > pmNE-mE > pmE-mNE.
Conclusions: Under conditions of the present study, abutment design affected the stress pattern with the restorative implant components. The lowest and the most balanced stress distribution was found for the pmE-mNE configuration.
Methods: Patients anatomy was digitized through CBCT and digitally designed dental implants were positioned in the lower right posterior area of teeth #’s 28 (premolar – pm) and 30 (molar – m). Restorative implant components (abutments, screws and FPD) were digitally designed and placed into the implant model. Four implant abutment situations were simulated through FEA: Both engaging abutments (pmE-mE), both non engaging (pmNE-mNE), premolar engaging and molar non-engaging (pmE-mNE), and premolar non-engaging and molar engaging (pmNE-mE). Thirty-five (35) Ncm preload to the screws and 160 N static load at 45-degree angle to the occlusal plane were applied in each group.
Results: The equivalent Von Mises stress was measured on each component. Stress distribution changed among the different configurations and ranged from 632 MPa to 1362 MPa in the implants, and from 581 MPa to 878 MPa with the abutments. The highest values for the implants were found for the NE designs (1146-1362 MPa). The lowest stress on both abutments was measured with the pmE-mNE configuration.
Engaging and non-engaging abutments had different stress distributions on the screw (626-830 MPa). Peak stress areas were located on the upper part of the screws for the non-engaging configuration, and on the lower areas for the engaging abutments. The sum of the stress on both screws decreased in the following order: pmNE-mNE > pmE-mE > pmNE-mE > pmE-mNE.
Conclusions: Under conditions of the present study, abutment design affected the stress pattern with the restorative implant components. The lowest and the most balanced stress distribution was found for the pmE-mNE configuration.
