Hugo Eduardo Peixoto1, Dimorvan Bordin2, Altair A Del Bel Cury3, Wander José da Silva4, Fernanda Faot5. 1. Implantology Team, Latin American Institute of Research and Education in Dentistry, Curitiba, Paraná, Brazil. Electronic address: hugo.e.peixoto@hotmail.com. 2. Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903, Brazil. Electronic address: dimorvan_bordin@hotmail.com. 3. Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903, Brazil. Electronic address: altcury@fop.unicamp.br. 4. Department of Prosthodontics and Periodontology, Piracicaba Dental School, State University of Campinas, Limeira avenue, 901-Vila Rezende, Piracicaba, SP 13414-903, Brazil. Electronic address: wanderjose@fop.unicamp.br. 5. Department of Restorative Dentistry, School of Dentistry, Federal University of Pelotas, Gonçalves Chaves, 457, 2nd floor, Pelotas, Rio Grande do Sul 96015-560, Brazil. Electronic address: fernanda.faot@gmail.com.
Abstract
PURPOSE: Evaluate the influence of abutment's material and geometry on stress distribution in a single implant-supported prosthesis. MATERIALS AND METHODS: Three-dimensional models were made based on tomographic slices of the upper middle incisor area, in which a morse taper implant was positioned and a titanium (Ti) or zirconia (ZrN) universal abutments was installed. The commercially available geometry of titanium (T) and zirconia (Z) abutments were used to draw two models, TM1 and ZM1 respectively, which served as control groups. These models were compared with 2 experimental groups were the mechanical properties of Z were applied to the titanium abutment (TM2) and vice versa for the zirconia abutment (ZM2). Subsequently, loading was simulated in two steps, starting with a preload phase, calculated with the respective friction coefficients of each materials, followed by a combined preload and chewing force. The maximum von Mises stress was described. Data were analyzed by two-way ANOVA that considered material composition, geometry and loading (p<0.05). RESULTS: Titanium and zirconia abutments showed similar von Mises stresses in the mechanical part of the four models. The area with the highest concentration of stress was the screw thread, following by the screw body. The highest stress levels occurred in screw thread was observed during the preloading phase in the ZM1 model (931MPa); and during the combined loading in the TM1 model (965MPa). Statistically significant differences were observed for loading, the material×loading interaction, and the loading×geometry interaction (p<0.05). Preloading contributed for 77.89% of the stress (p<0.05). There were no statistically significant differences to the other factors (p>0.05). CONCLUSION: The screw was the piece most intensely affected, mainly through the preload force, independent of the abutment's material.
PURPOSE: Evaluate the influence of abutment's material and geometry on stress distribution in a single implant-supported prosthesis. MATERIALS AND METHODS: Three-dimensional models were made based on tomographic slices of the upper middle incisor area, in which a morse taper implant was positioned and a titanium (Ti) or zirconia (ZrN) universal abutments was installed. The commercially available geometry of titanium (T) and zirconia (Z) abutments were used to draw two models, TM1 and ZM1 respectively, which served as control groups. These models were compared with 2 experimental groups were the mechanical properties of Z were applied to the titanium abutment (TM2) and vice versa for the zirconia abutment (ZM2). Subsequently, loading was simulated in two steps, starting with a preload phase, calculated with the respective friction coefficients of each materials, followed by a combined preload and chewing force. The maximum von Mises stress was described. Data were analyzed by two-way ANOVA that considered material composition, geometry and loading (p<0.05). RESULTS:Titanium and zirconia abutments showed similar von Mises stresses in the mechanical part of the four models. The area with the highest concentration of stress was the screw thread, following by the screw body. The highest stress levels occurred in screw thread was observed during the preloading phase in the ZM1 model (931MPa); and during the combined loading in the TM1 model (965MPa). Statistically significant differences were observed for loading, the material×loading interaction, and the loading×geometry interaction (p<0.05). Preloading contributed for 77.89% of the stress (p<0.05). There were no statistically significant differences to the other factors (p>0.05). CONCLUSION: The screw was the piece most intensely affected, mainly through the preload force, independent of the abutment's material.
Authors: María Prados-Privado; Sérgio A Gehrke; Rosa Rojo; Juan Carlos Prados-Frutos Journal: Med Biol Eng Comput Date: 2018-06-11 Impact factor: 2.602