examined the potential of PEEK as an alternative FPD material along with various fracture patterns and reported that CoCr registered the highest fracture values after thermocycling, followed by PEEK (3132 N) and zirconia all were within the clinically acceptable range. conducted a one-year in vivo longitudinal pilot study that assessed the prosthetic performance of PEEK crowns and found that 90% were satisfactory under the modified Ryge Criteria, with a low incidence of fracture. When compared with polylactic acid and PMMA in vitro, PEEK exhibits the lowest marginal and internal gap values and the greatest fracture resistance. Notably, PEEK is recommended as a long-term provisional crown material in cases where other auxiliary treatments are planned. Recent FEA modelling for implants with insufficient alveolar bone support has examined connected crowns, which can alleviate the stress concentrations at the margin of the crown and tooth. reached a different conclusion, however, as a veneered PEEK crown reduced the stress concentration in dentin, post, and composite core in comparison to the porcelain fused to metal crown, while increasing the stress concentration in the cement layer of the post and crown. Finite element analysis (FEA) has indicated that PEEK crowns and porcelain fused to metal crowns have similar stress distribution in dentin. found that crowns with PEEK coping exhibited much greater strength than crowns with zirconia coping, and thermocycling had minimal effect on fracture resistance. Regarding fracture resistance, PEEK exhibits superior flexural strength (140 to 170 MPa) compared to conventional materials, protecting restorations from bulk fractures. The PEEK crown exhibited increasing material loss along with the elevation of the cusp inclination, while showing minimum material loss in comparison to PMMA and SiO 2 after thermal loading. ![]() Regarding wear, an in vitro study comparing polymethylmethacrylate (PMMA), PEEK, and silicate ceramic (SiO 2) crowns demonstrated the pivotal role of crown geometry in crown preservation. and others have reported that zirconia crowns exhibit greater displacement resistance than PEEK crowns, but are also more abrasive, and although PEEK showed greater susceptibility to displacement compared to zirconia, it also shows a more balanced distribution of stress through deformation because of its much lower elastic modulus (3 to 4 GPa vs. Numerous authors have examined the wear resistance of PEEK crowns. ![]() ![]() Regular mastication and progressive erosion result in unavoidable wear of the crown, and the crown material must possess considerable wear resistance.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |